Document Kennewick_doc_e034212031

City of Kennewick City of Kennewick City of Kennewick City of Kennewick Comprehensive Comprehensive Comprehensive Comprehensive Stormwater Plan Stormwater Plan Stormwater Plan Stormwater Plan Final Prepared by: Aaron Meilleur, PE Aaron Meilleur, PE Aaron Meilleur, PE Aaron Meilleur, PE HDR, Inc. HDR, Inc. HDR, Inc. HDR, Inc. 2805 St. Andrews Lp., Suite A 2805 St. Andrews Lp., Suite A 2805 St. Andrews Lp., Suite A 2805 St. Andrews Lp., Suite A Pasco, WA 99301 Pasco, WA 99301 Pasco, WA 99301 Pasco, WA 99301 Joe Simmler, Ph.D. Joe Simmler, Ph.D. Joe Simmler, Ph.D. Joe Simmler, Ph.D. John Knutson, PE John Knutson, PE John Knutson, PE John Knutson, PE Otak, Inc. Otak, Inc. Otak, Inc. Otak, Inc. 620 Kirkland Way, 620 Kirkland Way, 620 Kirkland Way, 620 Kirkland Way, Suite Suite Suite Suite 100 00 00 00 Kirkland, Kirkland, Kirkland, Kirkland, WA 98033 WA 98033 WA 98033 WA 98033 January, 2007 ---PAGE BREAK--- Section 0 — Executive Summary C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-1 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc This document, entitled the City of Kennewick Comprehensive Stormwater Plan, provides information about the City’s existing stormwater management program and recommends a Comprehensive Stormwater Plan for the City. It presents capital facilities needed to accommodate existing and future growth, and proposes a regulatory compliance strategy to address federal and state stormwater requirements. It is the intent of this Comprehensive Stormwater Plan (SWP) to ensure that needed public storm and surface water (stormwater) facilities, as well as other stormwater- related programmatic services, are available to address existing drainage problems and allow continued future development throughout the city. Additionally, the City has submitted application to the Washington State Department of Ecology (Ecology) for compliance with the National Pollution Discharge Elimination System (NPDES) Phase II Municipal Stormwater Permit. The City’s application has been used as a guide, along with the State’s draft General NPDES Phase II Permit for Eastern Washington and the State’s Model Municipal Stormwater Program for Eastern Washington, for the development of a comprehensive strategy for achieving regulatory compliance over the next five years. Compliance with the State’s revised Underground Injection Control (UIC) Rule, as it affects the city’s numerous infiltration facilities, has also been included in this regulatory compliance strategy. The City completed a previous study to address stormwater needs for the City titled Comprehensive Flood Control and Storm Water Drainage Plan (Flood Study), prepared by JUB Engineers, Inc. (JUB) in 1990. With the completion of this current SWP, this study has updated and completed the following: • Development of a new hydrologic/hydraulic model of the City’s drainage system to account for City growth over the last 15 years and to anticipate growth over the next 20 years. • Updating and identifying new capital needs and associated costs for the anticipated growth. • Evaluation of the adequacy of the City’s existing Stormwater Program with respect to the Published Draft National Pollution Discharge Elimination System (NPDES) Phase II Municipal Stormwater Permit for Eastern Washington. • Development of a regulatory “Gap Analysis” and compliance strategy with program costs to bring the City’s stormwater program into compliance. • Review of proposed program’s financial needs and alternatives for enhanced funding. • Management recommendations and suggestions. • Implementation schedule that lists program priorities/activities and the annual budget, staffing, and equipment required for implementation. ---PAGE BREAK--- Section 0 — Executive Summary Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-2 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc This Executive Summary Section of the report highlights the significant findings of the study for the following areas evaluated in the report • City’s Existing Drainage System • Existing Water Quality • Existing Stormwater Program • Regulatory Compliance Requirements • Stormwater Program Recommendations for Regulatory Compliance • Capital Improvement Program • Project Program Funding Needs • Financial Alternatives and Funding Mechanisms City’s Existing Drainage System City’s Existing Drainage System City’s Existing Drainage System City’s Existing Drainage System The City of Kennewick Public Works Department manages and maintains the City’s drainage facilities. In their National Pollutant Discharge Elimination System Phase II Stormwater Permit Application (NPDES, 2002), the City estimated 4,200 catch basins in a network of 83 miles of piped storm sewers and open ditches, and three regional outfalls to the Columbia River. Incorporated within this regional drainage system, the City owns and operates an additional 2,000 public infiltration facilities (drywells), one local detention pond, three local retention facilities, and four regional stormwater detention/water quality treatment facilities, and associated inter- conveyance pipes, that accept about 75 percent of the area’s surface water runoff. In addition to City owned facilities, several major drainage facilities are owned and operated outside of the City’s control by the Army Corps of Engineers (Corps) and two local irrigation districts. Functionally, these Corps facilities and the canals provide regional detention during high rainfall events that help prevent localized flooding throughout the City. Based on this study’s evaluation of the existing stormwater system, the following highlight the study’s findings: • The City’s existing approach to stormwater management, by the infiltration of almost all stormwater runoff via drywells, works well in most locations. Where infiltration rates are too slow, localized flooding is a concern, and where infiltration rates are too fast, pollution of shallow groundwater is a concern. • Where drainage problems occur, it is usually the result of failing drywells, which have been located in soils that are inadequate for performing sustained rates of infiltration. Some of these failing drywells have been retrofitted by City crews. • The City should continue to use and enforce its drainage design standards for new developments. These standards should be upgraded to require all new developments to perform a analysis to the point of ultimate disposal or discharge. ---PAGE BREAK--- Section 0 — Executive Summary Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-3 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc • The City should establish a joint development review process, via an inter-local agreement with Benton County, to ensure new drainage facilities constructed within the City’s UGA are built according to the City’s drainage design standards. • The annual capital program should include funding to build or replace ponds and conveyance systems as the needs arise. As with drywell replacement, this is likely to be a growing annual need as surface runoff increases with continued development. • The inter-relationship between the City’s drainage system and the two regional irrigation systems warrants further study. Separating the two systems will likely increase demand on the City’s existing drainage system. A joint operational plan between the City and the irrigation districts could results in a seasonally based program that would assure continued harmonious operation of the two systems. Existing Water Quality Existing Water Quality Existing Water Quality Existing Water Quality Currently, there is little is known about the general water quality of the surface runoff that occurs throughout the greater Kennewick Stormwater Planning Area (City’s Urban Growth Area). There is little water quality monitoring data and no regular monitoring program conducted by the City or other agencies. With only four to seven inches of total rainfall, including snow and dew, there is very little runoff to monitor for the majority of the year. Water quality monitoring is not required under the current NPDES Permit. The presumptive guidance for water quality Best Management Practices in the Stormwater Management Manual for Eastern Washington (SMMEW) and the design guidance manual for the State UIC program are sufficient for compliance with NPDES Phase II. Existing Stormwater Program Existing Stormwater Program Existing Stormwater Program Existing Stormwater Program In general, the City has a good basis for developing a comprehensive stormwater program. Previous capital projects have largely eliminated flooding problems within the City and the existing maintenance activities are normally adequate to keep the stormwater system functioning on an annual basis. The City’s Stormwater Program exists as a series of services that are provided by staff from several divisions within the Municipal Services Department. Approximately 3.5 full time equivalent (FTE) staff support the City’s Municipal Services Department Stormwater Program on an annual basis. Most of the drainage staff are located within the Municipal Services Department, with 1.5 FTE in Engineering and 2.0 FTE in Maintenance. ---PAGE BREAK--- Section 0 — Executive Summary Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-4 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc The City’s stormwater related services are supported in the City’s annual budget from a combination of resources from the various departments. The City also charges plan review and inspection fees to partially cover the cost of regulating new development. The remainder of the City’s stormwater program (capital improvements) is supported by revenues generated from the City’s dedicated 0.5% sales tax for street related capital improvements. This study’s review of the existing structure, organization, staffing, funding, and equipment of the City’s present Stormwater Program has shown that: • The City of Kennewick has a well-established and well-working Stormwater Program that has evolved over time, as development and local drainage conditions have dictated. The Program wisely takes advantage of natural soils and groundwater conditions to dispose of stormwater in a way that requires relatively little capital investment or annual maintenance. • The Program is funded for its current types and levels of services, which include catch basin cleaning, drywell cleaning, plan review, construction site inspection, and minor capital repair and replacement projects. It has a dedicated, annual funding source from the City’s Street Fund and development related fees. • Although somewhat complex in its organizational structure and lines of communication, the Program seems to perform well on an annual basis. Each of the participating divisions and staffs know their respective roles and responsibilities. • There appears to be opportunities to work with neighboring jurisdictions to jointly develop and implement common stormwater program activities, such as public education and other activities associated with future regulatory compliance. • It would be a good investment to start a public education and outreach program to educate both citizens and local businesses. A higher focus should be placed on educating high risk businesses (gas stations, dry cleaners, manufacturers, material handlers, paint shops, transporters etc.) about what they can do to keep their stormwater runoff clean and pollutant free. • The City has stormwater needs that have not been met in terms of policies, ordinances, equipment, staffing, and retrofit projects for its system of drywells. Meeting these requirements may prove to be a challenge, requiring new activities and additional funding and staffing. • The City will need to expand their existing Stormwater Program to meet future regulatory requirements. ---PAGE BREAK--- Section 0 — Executive Summary C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-5 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc Table X Table X Table X Table X-1 City of Kennewick Existing SWM Program: Staffing Analysis City of Kennewick Existing SWM Program: Staffing Analysis City of Kennewick Existing SWM Program: Staffing Analysis City of Kennewick Existing SWM Program: Staffing Analysis Responsible Department Responsible Department Responsible Department Responsible Department Responsible Staff Responsible Staff Responsible Staff Responsible Staff Municipal Services Municipal Services Municipal Services Municipal Services Comm Dev Comm Dev Comm Dev Comm Dev Finance Finance Finance Finance Program E Program E Program E Program Element lement lement lement Engineering Engineering Engineering Engineering Maintenance Maintenance Maintenance Maintenance Director Director Director Director City City City City Eng. Eng. Eng. Eng. O/M O/M O/M O/M Super* Super* Super* Super* Eng Eng Eng Eng Staff Staff Staff Staff OM OM OM OM Staff* Staff* Staff* Staff* Inspector Inspector Inspector Inspector Planner Planner Planner Planner Code Code Code Code Enfor Enfor Enfor Enfor Finance Finance Finance Finance Assist Assist Assist Assist 1. Admin 1. Admin 1. Admin 1. Admin 0.15 0.15 0.15 0.15 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 2. CIP 2. CIP 2. CIP 2. CIP 0.10 0.10 0.10 0.10 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 3. O/M 3. O/M 3. O/M 3. O/M 0.10 0.10 0.10 0.10 1.80 1.80 1.80 1.80 0.05 0.05 0.05 0.05 0.10 0.10 0.10 0.10 0.05 0.05 0.05 0.05 1.70 1.70 1.70 1.70 4. Dev. Review 4. Dev. Review 4. Dev. Review 4. Dev. Review 0.35 0.35 0.35 0.35 0.05 0.05 0.05 0.05 0.30 0.30 0.30 0.30 5. Pub. Ed. 5. Pub. Ed. 5. Pub. Ed. 5. Pub. Ed. 6. Inspect/Enforce 6. Inspect/Enforce 6. Inspect/Enforce 6. Inspect/Enforce 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 7. Compliant/Emergency 7. Compliant/Emergency 7. Compliant/Emergency 7. Compliant/Emergency Response Response Response Response 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 8. Watershed/GMA Planning 8. Watershed/GMA Planning 8. Watershed/GMA Planning 8. Watershed/GMA Planning 9. Critical Areas, Wetland 9. Critical Areas, Wetland 9. Critical Areas, Wetland 9. Critical Areas, Wetland 10. Tech. Support 10. Tech. Support 10. Tech. Support 10. Tech. Support 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 11. Regional Coord. 11. Regional Coord. 11. Regional Coord. 11. Regional Coord. 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 12. NPDES II 12. NPDES II 12. NPDES II 12. NPDES II 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 13. UIC Rule 13. UIC Rule 13. UIC Rule 13. UIC Rule 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 14. ESA 14. ESA 14. ESA 14. ESA 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 15. Debt & Taxes 15. Debt & Taxes 15. Debt & Taxes 15. Debt & Taxes 16. Equipment 16. Equipment 16. Equipment 16. Equipment 17. Repair / Replace 17. Repair / Replace 17. Repair / Replace 17. Repair / Replace 18. WQ / Monitoring 18. WQ / Monitoring 18. WQ / Monitoring 18. WQ / Monitoring 19. Legal / Ordinances 19. Legal / Ordinances 19. Legal / Ordinances 19. Legal / Ordinances 20. Legal Advice/Support 20. Legal Advice/Support 20. Legal Advice/Support 20. Legal Advice/Support 21 21 21 21. Outside Services . Outside Services . Outside Services . Outside Services 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 Total FTE Count 1.55 1.55 1.55 1.55 1.95 1.95 1.95 1.95 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.05 0.05 0.05 0.05 0.20 0.20 0.20 0.20 0.15 0.15 0.15 0.15 1.30 1.30 1.30 1.30 1.80 1.80 1.80 1.80 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Total Total Total Total 3.5 3.5 3.5 3.5 3.5 FTE 3.5 FTE 3.5 FTE 3.5 FTE *Maintenance responsibilities are shared between Public Works maintenance and operations, and parks, streets, and facilities maintenance and operations. ---PAGE BREAK--- Section 0 — Executive Summary Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-6 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc This page intentionally left blank. ---PAGE BREAK--- Section 0 — Executive Summary C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-7 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc Regulatory Compliance Regulatory Compliance Regulatory Compliance Regulatory Compliance Requirements Requirements Requirements Requirements Evaluation of the existing stormwater program compared ongoing program activities to the six minimum requirement of the NPDES Phase II Municipal Stormwater Permit, as described by the Environmental Protection Agency in the federal register (December, 1999). The six minimum requirements include the following: NPDES #1 — Public Education and Outreach NPDES #2 — Public Involvement and Participation NPDES #3 — Illicit Discharge Detection and Elimination NPDES #4 — Construction Site Stormwater Runoff Control NPDES #5 — Post-Construction Stormwater Management for New Development and Redevelopment NPDES #6 — Pollution Prevention and Good Housekeeping for Municipal Operations In addition to these six minimum pollution control measures, NPDES also requires: Compliance with Total Maximum Daily Load requirements for specific pollutants, and Regular program tracking and documentation, success in implementation as determined by water quality monitoring, and annual reporting to Ecology The existing program evaluation also included the impacts associated with the Underground Injection Control (UIC) Rule. Due to the presence of an extensive system of over 2,000 drywells, complying with the UIC Rule will be a significant part of the City’s new stormwater management program. According to this law, the City’s stormwater must meet drinking water and/or groundwater quality standards before it comes into contact with the region’s shallow aquifers. Stormwater Program Stormwater Program Stormwater Program Stormwater Program Recommendations for Regulatory Compliance Recommendations for Regulatory Compliance Recommendations for Regulatory Compliance Recommendations for Regulatory Compliance The following are highlights of the recommendations made by this study for the City’s Stormwater Program: • The City is likely to need approximately 3.4 FTE in the Municipal Services Department at an additional annual cost of about $600,000 to achieve full regulatory compliance by Year 5 of the program. This more than doubles the existing staffing and staff funding levels. • NPDES compliance alone will likely require 3.2 additional FTE at an additional annual cost of about $450,000 per year. • The City’s public education program needs improvement. A formal education strategy and implementation plan is needed to begin distributing stormwater information to the public and to business owners (NPDES #1 & • The City needs an ordinance relating to erosion and sediment control for ---PAGE BREAK--- Section 0 — Executive Summary Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-8 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc construction sites disturbing one or more acres (NPDES • The City’s stormwater management development ordinance(s) needs to be updated and standards need to be enhanced to match: the minimum technical requirements for development and redevelopment in the final NPDES II permit; the SWMM for Eastern Washington (construction and post-construction stormwater control BMPs), the presumptive standards of the final Determination of Treatment and Source Control Requirements for UIC Wells in Washington State (or locally developed demonstrative standards)(NPDES #5 & UIC). • UIC compliance will likely require an additional 0.25 FTE at an additional annual cost of $354,000 annually if implemented in conjunction with NPDES II programs. The 5-year average UIC Water Quality Capital project cost is estimated at about $329,000 per year beginning in 2007 (See Section This would bring the total additional UIC program cost to about $354,000 per year. • The City needs to develop a formal plan to identify, monitor, retrofit, and/or decommission high-risk UICs. An initial plan and recommendations have been developed with this study and are included in Section 7 of this report. • Annual and total costs are presented in Section 9, along with an annual implementation plan that meets the interim milestones and due dates prescribed in the draft General NPDES II Municipal Stormwater Permit for eastern Washington. Full compliance with the General NPDES II Permit is achieved at the end of the five year permit planning process. Table X-2 outlines the program evaluation conducted by the study and the identified gaps in funding. In general, the City has a number of areas where current efforts under the existing stormwater program are well on their way to meeting the regulatory requirements of NPDES Phase II. These include public involvement / participation, illicit discharge elimination, post-construction stormwater management, and monitoring and record keeping. Areas that require additional attention are public education, construction site stormwater runoff control, and pollution prevention / good house keeping. ---PAGE BREAK--- Section 0 — Executive Summary Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-9 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc Insert Table x.2 ---PAGE BREAK--- Section 0 — Executive Summary Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-10 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc Insert Table x.2c ---PAGE BREAK--- Section 0 — Executive Summary Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-11 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc Capital Improvement Program Capital Improvement Program Capital Improvement Program Capital Improvement Program In addition to the regulatory compliance activities evaluated under this study, an evaluation of the capital needs was also completed. A total of ten projects were identified for the Capital Improvement Program (CIP); three projects to address existing and future system capacity deficiencies; six projects to address specific water quality concerns by removing drywells; and one long-term project to retrofit drywells within the aquifer recharge area. Only four of the projects are recommended to be completed within the permit 5 year cycle. The City’s 5-year CIP cost is estimated to be $1.8 Million. With projects occurring over a number of years, the annual costs of the CIP to the Stormwater program are between $100,000 and $650,000 for the first five years ($360,000 annual average). Existing City staffing levels should be adequate to administer the CIP. No additional FTEs are needed. Stormwater Stormwater Stormwater Stormwater Program Funding Program Funding Program Funding Program Funding Needs Needs Needs Needs The annual revenue needs for the City’s fully implemented, enhanced Surface Water Program (at the end of the first five-year NPDES Permit Period) are $1.41 M, as shown below. • For Operations (current program of $350K, plus new costs of $700K): .$1,050,000 • For Capital Improvements (Approx. 5-year average annual cost): ....$360,000 Annual total: $1,410,000 This estimate assumes that the City takes a “pay as you go” approach to CIPs rather than funding them over a longer term, or using other capital funding mechanisms such as bonding. The pay as you go approach requires the City to begin raising about $360K in annual CIP funding starting in 2007 and continuing through 2011. The annual operational costs, estimated at $1050K in 2011, can begin at a lower level in 2007 and then slowly increase as programs are put into place to comply with NPDES required activities and schedules. Financial Alternatives and Funding Mechanisms Financial Alternatives and Funding Mechanisms Financial Alternatives and Funding Mechanisms Financial Alternatives and Funding Mechanisms The City of Kennewick routinely uses various revenue sources and funding mechanisms to operate its existing SWM program, which consists of constructing capital improvement projects on an as needed basis, and conducting annual maintenance. The primary source of funding is the existing City-wide 0.5% sales tax, which has historically generated $400-450K per year for the City’s existing stormwater needs, primarily maintenance. To date, the sales tax has adequately ---PAGE BREAK--- Section 0 — Executive Summary Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 0-12 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 0.doc served the City’s Stormwater Management Program and still remains a viable funding source to help address the City’s new regulatory compliance and capital needs. However, future stormwater program funding is scheduled to be reduced to approximately 350K per year due to budgeting within the City. To create the enhanced level of surface water revenue needed to support the City’s SWM program, several funding mechanisms may be considered ranging from forming a stormwater utility to establishing long-term inter-local cost sharing agreements. Analysis of potential storm utility rates are provided in Section 8. ---PAGE BREAK--- Table of Contents City of Kennewick Comprehensive Stormwater Plan i hdr/otak Section 1 Section 1 Section 1 Section 1 — Introduction Introduction Introduction Introduction Background and 1-1 Goals and 1-2 Format and Organization of this 1-2 Section 2 Section 2 Section 2 Section 2 — Summary of the City’s 1990 Flood / Stormwater Plan Summary of the City’s 1990 Flood / Stormwater Plan Summary of the City’s 1990 Flood / Stormwater Plan Summary of the City’s 1990 Flood / Stormwater Plan Background 2-1 Goals and 2-1 Major Findings, Results, and 2-1 Building Upon the City’s 1990 Flood/Stormwater 2-5 Section 3 Section 3 Section 3 Section 3 — Drainage Area Characterization Drainage Area Characterization Drainage Area Characterization Drainage Area Characterization Description of the Planning Area 3-1 Summary of Drainage Area Characterization Section 4 Section 4 Section 4 Section 4 — Existing Stormwater Program Existing Stormwater Program Existing Stormwater Program Existing Stormwater Program City’s Existing Drainage System: An 4-1 Major Drainage 4-2 Manmade Drainage 4-6 Complaints and Documented Drainage Problems Role of Existing Stormwater Section 5 Section 5 Section 5 Section 5 — Analysis of Existing Stormwater Program Analysis of Existing Stormwater Program Analysis of Existing Stormwater Program Analysis of Existing Stormwater Program Introduction 5-1 Existing Stormwater Program 5-1 Preliminary Evaluation of the City’s Existing Stormwater Summary of Program and Needs Section 6 Section 6 Section 6 Section 6 — Regulatory Gap Analysis and Compliance Strategy Regulatory Gap Analysis and Compliance Strategy Regulatory Gap Analysis and Compliance Strategy Regulatory Gap Analysis and Compliance Strategy An Introduction to Regulatory Compliance 6-1 Regulatory Requirements: Compliance Strategy & 6-2 Federal: Endangered Species 6-8 State/Federal: NPDES Construction Stormwater General Permit... 6-9 State: Stormwater Management Manual for Eastern Washington..6-11 State/Federal: Wellhead Protection State Water Quality: Impaired Water Bodies, State Watershed Planning Act Additional Stormwater Related Regulations Summary of the City’s Existing Regulatory Compliance Activities.6-13 Regulatory Compliance ---PAGE BREAK--- Table of Contents City of Kennewick Comprehensive Stormwater Plan ii hdr/otak Section 7 Section 7 Section 7 Section 7 — Cap Cap Cap Capital Improvement Program Development ital Improvement Program Development ital Improvement Program Development ital Improvement Program Development Introduction 7-1 Hydrologic and Hydraulic 7-1 Model Input 7-2 Capacity Problems/Model Analysis 7-5 Water Quality Analysis 7-7 Underground Injection Control 7-9 Water Quality Capital Improvement Plan System Deficiencies Water Quality Section 8 Section 8 Section 8 Section 8 — Funding Funding Funding Funding Revenue 8-1 Current Funding Mechanisms 8-2 Financial Alternatives and Funding 8-2 Recommended Funding 8-7 Recommended Financial Plan & Preliminary Utility 8-8 Comparison to Local Communities Section 9 Section 9 Section 9 Section 9 — Public Involvement Public Involvement Public Involvement Public Involvement Public Involvement: An 9-1 Figures Figures Figures Figures Figure 3-1 — Vicinity Map of Section 3 Figure 3-2 — Study Area and Land Use of Section 3 Figure 3-3 — of Section 3 Figure 3-4 — Major Drainage of Section 3 Figure 3-5 — Soils – of Section 3 Figure 3-6 — Soils – Hydrologic of Section 3 Figure 3-7 — Geological Map and Section Locations.....end of Section 3 Figure 3-8 — Geologic Cross-Section E-E of Section 3 Figure 3-9 — Sensitive and Critical of Section 3 Figure 4-1 — Existing Drainage Conditions..................end of Section 4 Figure 4-2 — Man-Made Drainage of Section 4 Figure 4-3 — Storm of Section 4 Figure 4-4 — Existing System of Section 4 Figure 4-5 — Previous Study Capital Projects of Section 4 Figure 5-1 — Municipal Services 5-4 Figure 5-2 — Major Stormwater Services and Staffing Levels 5-5 ---PAGE BREAK--- Table of Contents City of Kennewick Comprehensive Stormwater Plan iii hdr/otak Figure 7-1 — Stormwater of Section 7 Figure 7-2 — Modeled of Section 7 Figure 7-3 — Existing Land of Section 7 Figure 7-4 — Future Land Use of Section 7 Figure 7-5 — Hydrograph 7-4 Figure 7-6a — 25-Yr Storm Flooding (Existing) of Section 7 Figure 7-6b — 25-Yr Storm Flooding (Proposed)...........end of Section 7 Figure 7-6c — Future Gutter Flow Concerns 25-Year Storm Event of Section 7 Figure 7-6d — Proposed Stormwater CIP Projects........end of Section 7 Figure 7-7a — UIC Pretreatment Requirements...........end of Section 7 Figure 7-7b — Pollutant Loading for of Section 7 Figure 7-7c — Predicted Soil Infiltration of Section 7 Figure 7-7d — Avg Depth to Seasonal Groundwater.....end of Section 7 Figure 7-7e — Presumed Treatment Capacity of Section 7 Figure 7-8a — Modeled 25-Year Storm Ponding and Line Figure 7-8b — North Edison Street Drainage Improvements..........7-23 Figure 7-9a — Modeled 25-Year Storm Ponding and Ditch Figure 7-9b — South Garfield Drainage Improvements...................7-27 Figure 7-10a — Modeled 25-Year Storm Ponding and Pipe Capacity Figure 7-10b — West Columbia Drive and North Garfield Street Drainage Figure 7-11 — Aquifer UIC of Section 7 Exhibit Exhibit Exhibit Exhibits Exhibit 7-1 — UIC Management Areas Tables Tables Tables Tables Table 3-1 — Common Soils of the Kennewick Stormwater Study Area 3-5 Table 4-1 — Capital Project Prioritization Matrix Table 4-2 — Stormwater Discharges into CID Canals Table 5-1 — City of Kennewick Stormwater Program: Staffing Analysis 5-6 Table 6-1 — Summary of City’s March 2003 NPDES II: Notice of Intent Table 6-2 — Gap Analysis Summary ---PAGE BREAK--- Table of Contents City of Kennewick Comprehensive Stormwater Plan iv hdr/otak Table 7-1 — Treatment Capacity of Vadose Zone Materials for Removing Solids, Metals, and Oil from Stormwater Discharged to UIC Facilities Table 7-2 — Pollutant Loading Classifications for Solids, Metals, and Oil in Stormwater Runoff Directed to UIC Table 7-3 — Matrix for Determining Suitability of Subsurface Discharge of Stormwater from Commercial and Residential Land Uses to New UIC Facilities Without Structural Pre-Treatment to Remove Solids, Metals and Table 7-4 — Soil Infiltration Assumptions Used for Planning Documents Table 7-5 — Budget and Table 7-6 — Engineer’s Opinion of Probable Cost: Project C1 Table 7-7 — Engineer’s Opinion of Probable Cost: Project C3 Table 7-10 — Documented Public Drywells per UIC Management Table 7-11 — Engineer’s Opinion of Probable Cost: CB Retrofit Table 8-1 — Estimated Annual Program Costs and Required Table 8-2 — Funding Alternatives and Impacts on Existing City Funds and Possible Utility Table 8-3 — Funding Alternative #2 Rates - Utility Paying Only New Costs, With and Without Table 8-4 — Funding Alternative #3 Rates - Utility Paying Full Costs, With and Without CIPs Appendices Appendices Appendices Appendices Appendix A — City's Ordinances and Legal Authorities Appendix B — Initial Data Request Appendix C — December 18, 2003 Site Visit: Meeting Minutes Appendix D — Regulatory Compliance Analysis Appendix D.1 — Existing Stormwater Program Appendix D.2 — Preliminary Compliance Strategy to Meet NPDES Stormwater Phase II Requirements Appendix D.3 — Gap Analysis and Compliance Strategy Appendix E — NPDES II Permit Application to Ecology Appendix F — Stormwater Program Analysis Questionnaire: City's Response Appendix G — Hydrologic and Hydraulic Modeling Appendix H — Water Quality BMPs ---PAGE BREAK--- Table of Contents City of Kennewick Comprehensive Stormwater Plan v hdr/otak Table of Abbreviations and Acronyms Table of Abbreviations and Acronyms Table of Abbreviations and Acronyms Table of Abbreviations and Acronyms 2003 Ecology SWM Manual 2003 Stormwater Management Manual for Eastern Washington BMP Best Management Practice CIP Capital Improvement Program City City of Kennewick County Benton County CSWP Comprehensive Stormwater Plan Ecology Washington State Department of Ecology ESA Endangered Species Act GFC General Facilities Charge GMA Growth Management Act HEC-RAS Hydrologic Engineering Center – River Analysis System HSPF Hydrologic Simulation Program Fortran NOI Notice of Intent (For NPDES II Municipal Stormwater Permit) NPDES National Pollution Discharge Elimination System NPDES II National Pollution Discharge Elimination System – Phase II O/M Operations and Maintenance PIE Public Involvement Education Planning City of Kennewick Community Development and Planning Department R/D Retention/Detention SDC System Development Charge SWM Surface Water Management UGA Urban Growth Area UIC Underground Injection Control Rule WSDOT Washington State Department of Transportation ---PAGE BREAK--- Section 1 — Introduction C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 1-1 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 1.doc Background and Purpose Background and Purpose Background and Purpose Background and Purpose The City of Kennewick (City) has established a well-defined Comprehensive Land Use Plan, the full development of which is contingent on the development of needed infrastructure. It is the intent of this Comprehensive Stormwater Plan (SWP) to ensure that needed public storm and surface water (stormwater) facilities, as well as other stormwater-related programmatic services, are available to address existing drainage problems and allow continued future development throughout the city. This includes effective use of existing revenue sources and the creation of adequate revenue sources to accommodate future growth and economic development. This document, entitled the City of Kennewick Comprehensive Stormwater Plan, provides information about the City’s existing stormwater management program and recommends a Comprehensive Stormwater Plan for the City. It presents capital facilities needed to accommodate existing and future growth, and proposes a regulatory compliance strategy to address federal and state stormwater requirements. The application, submitted by the City to the Washington State Department of Ecology (Ecology) prior to March 10, 2003 for compliance with the National Pollution Discharge Elimination System (NPDES) Phase II Municipal Stormwater Permit, has been included in the Technical Appendices. It has been used as a guide, along with the State’s draft General NPDES Phase II Permit for Eastern Washington and the State’s Model Municipal Stormwater Program for Eastern Washington, for the development of a comprehensive strategy for achieving regulatory compliance over the next five years. Compliance with the State’s proposed Underground Injection Control (UIC) Rule, as it affects the city’s numerous infiltration facilities, has also been included in this regulatory compliance strategy. The City’s stormwater capital needs and costs have been identified in earlier studies, including the Comprehensive Flood Control and Storm Water Drainage Plan prepared by JUB Engineers, Inc. (JUB) in 1990. This study analyzed the previous JUB hydrologic/hydraulic model and revised it to develop an updated hydrologic/hydraulic model of the City’s drainage system. The updated model was used to identify new capital needs and associated costs. This study also analyzed the adequacy of the City’s existing Stormwater Program. Section 7 presents a series of recommended capital enhancements, an estimate of needed resources, costs and funding mechanism(s), and a prioritized implementation plan for activities and projects. It also presents a future vision for the City to work in cooperation with the County and other adjacent agencies, as appropriate, in order to respond to the needs of future development throughout the region. ---PAGE BREAK--- Section 1 — Introduction Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 1-2 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 1.doc Goals and Objectives Goals and Objectives Goals and Objectives Goals and Objectives One of the main reasons for the City to undertake this current study is to update the City’s existing Flood/Stormwater Plan, as developed by JUB in 1990 (JUB Engineers, 1990). A number of conditions warrant this update, including recent and sustained growth within the City, and the emergence of a series of stormwater related regulatory requirements, including the NPDES Phase II Municipal Stormwater Permit and the State’s new UIC Rule. Since 1990, a series of regulatory requirements has emerged which the City needs to respond to including: • The recent regulatory requirement of the City to apply for and be in compliance with a new NPDES II Municipal Stormwater Permit (federal register December 1999), to be issued to the City by Ecology in June 2006, • The technical guidance document, Model Stormwater Program for Eastern Washington (September 2003), suggests that the City’s stormwater program and stormwater design criteria be equivalent to the Stormwater Management Manual (SWMM) for Eastern Washington, • The new requirement for all of the City’s drywells to be registered, properly located/designed, and routinely maintained per the revised Underground Injection Control Rule (draft June 2006, expected issuance January 2007), and • The need for the City’s stormwater design criteria to be equivalent to the Eastern Washington Stormwater Design Manual (September, 2003). Thus, the objective of this study is to review and update the City’s existing Stormwater Program so that it is consistent with current regulatory requirements, supports the City’s Comprehensive Land Use Plan, and can be locally afforded and implemented in a phased approach, over a twelve year planning period. Format and Organization of this Report Format and Organization of this Report Format and Organization of this Report Format and Organization of this Report This report is the final product associated with the creation of the City of Kennewick Comprehensive Stormwater Plan. This report follows the outline previously approved by the City and includes: • A summary of the 1990 Flood/Stormwater Plan, • Information characterizing the drainage basins within the study area, • A review of the City’s existing drainage system and stormwater facilities, • A series of exhibits presenting GIS-based mapping and facility information collected to date, and as provided by the City. • Documentation of the City’s existing stormwater program, • A review of stormwater regulatory requirements, • The results of hydrologic/hydraulic modeling of the study area, ---PAGE BREAK--- Section 1 — Introduction Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 1-3 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 1.doc • An updated list of capital improvement projects and their costs, • A regulatory “Gap Analysis” and compliance strategy with program costs, • Review of financial alternatives, • Management recommendations and suggestions, and • A Schedule that lists program priorities/activities and the annual budget, staffing, and equipment required for implementation. ---PAGE BREAK--- Section 2 — Summary of the City’s 1990 Flood / Stormwater Plan C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 2-1 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 2.doc Background Background Background Background In 1987, the City of Kennewick contracted with JUB Engineers, Inc. to develop the City’s first Comprehensive Flood Control and Storm Water Drainage Plan. While the emphasis was on the identification of capital projects to reduce flooding, many stormwater management issues including policies, local ordinances, regulatory compliance, groundwater, irrigation canals, and water quality were also addressed. The information presented in this earlier plan has been used as technical background and baseline information in the development of this Comprehensive Stormwater Plan. Key goals, findings, and recommendations of the 1990 Kennewick Comprehensive Flood Control and Storm Water Drainage Plan are summarized below. Goals and Objectives Goals and Objectives Goals and Objectives Goals and Objectives The intent of the 1990 Kennewick Comprehensive Flood Control and Storm Water Drainage Plan was: • To be used as a tool to analyze and plan facilities to manage stormwater flow and reduce flooding, • To provide a guideline and a unified set of policies for both private and public entities to follow. • To result in an “orderly progression of a planned utility”, that “will minimize waste by avoiding the expense of future retrofits and upgrades when systems are installed in an unplanned drainage system.” Major Findings, Results, and Major Findings, Results, and Major Findings, Results, and Major Findings, Results, and Recommendations Recommendations Recommendations Recommendations Major findings of the 1990 Plan are listed below. Major Conclusions Major Conclusions Major Conclusions Major Conclusions, Results, and Recommendations , Results, and Recommendations , Results, and Recommendations , Results, and Recommendations: p.1 : p.1 : p.1 : p.1-1, 1 , 1 , 1 , 1-2 • There is an urgent need for a comprehensive flood control and stormwater drainage plan in the City of Kennewick. • Subsurface disposal of stormwater is the most cost-effective approach for areas where subsurface conditions are favorable. For areas unsuitable for subsurface disposal, stormwater flows should be conveyed in pipe systems or natural drainageways, to a point of final discharge. • Construction of the Zintel Canyon Dam and Conveyance System (which has since been completed) is critical to the public safety of the City of Kennewick and its citizens. • Storm water flow shall be limited to natural state rates through the use of regulation devices, such as controlled inlets and detention reservoirs. ---PAGE BREAK--- Section 2 — Summary of the City’s 1990 Flood / Stormwater Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 2-2 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 2.doc • Discharge points to natural water shall be limited, facilitating central treatment of the stormwater prior to discharge to the Columbia River. • Wetlands, along with man-made detention facilities, shall be utilized to reduce peak flow and sediment levels. • The natural state flow rate shall be based on a ten-year return period summer thunderstorm event. Detention reservoirs regulating outflow shall be sized for volume by using the twenty-year return period thunderstorm event. Peak hydraulic capacity and volume sizing shall be based on the twenty-year summer thunderstorm. Local Flooding: p.2 Local Flooding: p.2 Local Flooding: p.2 Local Flooding: p.2-2 • Flooding has been primarily associated with drainage from the 19 square mile Zintel Canyon watershed. “There has been little known flood events during the non-winter months due to thunderstorms because most precipitation can be adsorbed into the pervious soil.” City’s Traditional Approach to Stormwater: p. 2 City’s Traditional Approach to Stormwater: p. 2 City’s Traditional Approach to Stormwater: p. 2 City’s Traditional Approach to Stormwater: p. 2-2 • Traditionally, the approach to stormwater management within Kennewick has been to retain stormwater on each property and use of drywells to dispose of the water below ground. • Many of the City’s streets are paved in asphalt with a shallow ditch or slight relief on each side of the pavement; stormwater is absorbed in the soil areas and excess runoff exceeding the infiltration rate puddles and ponds in low areas, and dissipates over time. • During major precipitation events, or during winter months when the ground is frozen, large amounts of water collects and ponds causing damage to properties and structures in different areas throughout the City. • Most streets constructed within the last fifteen years have curb and gutter systems to collect and confine street runoff. In most areas, the gutter systems deliver water to drywells constructed within the street corridor for ultimate disposal. Role of Irrigation Canals: p. 2 Role of Irrigation Canals: p. 2 Role of Irrigation Canals: p. 2 Role of Irrigation Canals: p. 2-4, 2 4, 2 4, 2 4, 2-5, 5 5, 5 5, 5 5, 5-4 • There is an increased presence of surface water flow due to new springs and other shallow groundwater conditions within the City. • Areas south of the Kennewick Irrigation District Division Four Canal drain north where surface water is intercepted by the canal. Exceptions occur at the major canyons, where the canal water crosses the canyon through a buried inverted siphon. These types of crossings occur at Zintel, Garfield, Cascade, and Elliot Lake Canyons. ---PAGE BREAK--- Section 2 — Summary of the City’s 1990 Flood / Stormwater Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 2-3 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 2.doc Types of Soils: p.2 Types of Soils: p.2 Types of Soils: p.2 Types of Soils: p.2-6 • Topsoils are similar throughout the study area but subsoils, vegetation and development of the area vary from basin to basin. • Loose sandy soils with some rock outcrops overlie basalts in the upper part of the study area, while the lower portion of the basin consists of an agglomerate of materials from the upper study area. • The upper part of the study area has a moderate depth of soil mantle and a sparse vegetative cover of sagebrush, native grasses and weeds. Two Types of Flood Two Types of Flood Two Types of Flood Two Types of Floods: p.2 : p.2 : p.2 : p.2-6 • In general, the winter rainfall events that cause flooding, either with or without snowmelt, produce relatively low peak flows but are characterized by large runoff volumes and longer duration flooding (i.e. one to three days). • Floods from summer thunderstorms, on the other hand, have extremely high peak flows, relatively small runoff volumes, and shorter flooding durations. Existing Stormwater Facilities: p. 3 Existing Stormwater Facilities: p. 3 Existing Stormwater Facilities: p. 3 Existing Stormwater Facilities: p. 3-1 • Stormwater drainage systems in the City of Kennewick consist primarily of three types: - Catch basins and solid pipelines collecting stormwater from curbed streets and transporting it for release into drainways, canals, or the Columbia River. - Individual drywells collecting and disposing of runoff to subsurface soils. In some cases, drywells are interconnected via smaller diameter overflow pipes. Some drywells have overflows to surface conveyance systems. - Shallow ditch sections along the roadways both infiltrate and transport surface water to natural discharge locations. Culverts carry water under City streets. • Within the City limits, roughly half of the streets have no stormwater drainage system, other than a shallow ditch to facilitate local infiltration. Use of Drywel Use of Drywel Use of Drywel Use of Drywells: p. 3 ls: p. 3 ls: p. 3 ls: p. 3-2 • The majority of existing storm drainage systems consist of individual drywells constructed from a 6-foot diameter perforated pipe. An envelope of drainage rock and filter fabric surround the perforated manhole sections of the drywell to provide ample below ground storage. Typically, these drywells are at least nine feet deep and, in some cases, as deep as 25-30 feet. They are constructed to a depth which intercepts a pre-tested strata of highly permeable soil. Most drywells are connected with solid pipe to two or three catch basins. • There are a number of areas where significant drywell failure has occurred. ---PAGE BREAK--- Section 2 — Summary of the City’s 1990 Flood / Stormwater Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 2-4 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 2.doc • In many areas of the City, maintenance crews must post signs several times each year warning of “Water over Street” and pump excess water to alleviate accumulations and prevent damage to private property. • In addition to the unwanted accumulations of water along the roadside ditches, City crews often respond to flooding of streets where drywells were installed in poor draining soils. A number of these locations require a substantial labor force nearly every time it rains to install pumps and remove water overflowing from failed drywells. Drainage System Deficiencies: p. Drainage System Deficiencies: p. Drainage System Deficiencies: p. Drainage System Deficiencies: p. 3-3 • A number of areas within Kennewick presently have failed or have deficient stormwater drainage systems. These systems flood roadways and allow excess water to flow onto private property. • Primarily, problem areas within the City include: - Drywells without interconnecting overflow pipes, which have reduced, or no infiltration capabilities. - Roadway ditches and culverts which have filled in with sediment and have lost their capacity to convey surface water. - Undersized pipe conveyance systems, which hydraulically do not have sufficient capacity to meet local drainage needs. • Of these existing deficiencies, the drywell failure is by far the greatest and most prevalent concern within the City’s study area. • Retrofitting, using an interconnecting system of solid pipes between adjacent drywells has proven successful to date, but its long-term success depends upon the life expectancy of the drywells. • Little is known about the long term trends and life expectancy for surface drywells in the Kennewick area. This casts some uncertainty about the use of drywells in Kennewick, particularly in marginal soil areas. Water Quality Concerns: p. 3 Water Quality Concerns: p. 3 Water Quality Concerns: p. 3 Water Quality Concerns: p. 3-4 • In addition to collecting and removing water at a rate sufficient to avoid a water hazard, an equally important aspect of a stormwater system is to maintain the highest water quality possible and to prevent further erosion. • Concern is increasing with regard to the impact stormwater has on our lakes, rivers, and streams. • The impact stormwater may have on groundwater resources is of equal concern. City Building Code: 4 City Building Code: 4 City Building Code: 4 City Building Code: 4-3, 4 3, 4 3, 4 3, 4-6, 4 6, 4 6, 4 6, 4-9 • The City of Kennewick has adopted the 2003 International Building Code (IBC). The IBC contains no special regulations regarding construction in floodplains. However, the City requires a flood prone area development permit for any work ---PAGE BREAK--- Section 2 — Summary of the City’s 1990 Flood / Stormwater Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 2-5 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 2.doc within the floodplain as established by the Kennewick Municipal Code, Chapter 18.93 – Flood Damage Prevention (Rev. date March 5, 1990). • Zoning and comprehensive plans are used to regulate development, particularly residential development, in hazardous areas such as floodplains. • The City of Kennewick has chosen to participate in the National Flood Insurance Program to gain the benefits of low cost flood insurance and other federal assistance for local, residents, taxpayers, and small businesses. Proposed Capital Projects and Their Current Status: p.9 Proposed Capital Projects and Their Current Status: p.9 Proposed Capital Projects and Their Current Status: p.9 Proposed Capital Projects and Their Current Status: p.9-8 • Five capital projects totaling $1.96M were recommended: 1. South Rainier Pipeline – Conveyance enhancement associated with Zintel Canyon Dam Project; City’s local match to $6.7M Corps of Engineers Grant. ($1.57M) – Project Completed 2. Kennewick Park Subdivision – Pipe to connect failing drywells ($100K) – Project Completed 3. Drywell Replacements ($100K) – Ongoing Project in City’s CIP as funding allows 4. Conway Pipeline – Upgrade pipe channel and add R/D basin (COST) – In City’s CIP; 70% complete 5. Garfield Pipeline – Install 3,200 feet of large diameter pipe (COST) – In City’s CIP; alternative solutions are in design phase Buil Buil Buil Building Upon the City’s 1990 Flood ding Upon the City’s 1990 Flood ding Upon the City’s 1990 Flood ding Upon the City’s 1990 Flood/Stormwater Plan /Stormwater Plan /Stormwater Plan /Stormwater Plan This study builds upon and updates much of the information originally presented in the 1990 Flood/Stormwater Plan. It models the City’s existing stormwater facilities and presents a strategy to achieve compliance with the various stormwater-related regulations that have been created since the 1990 Flood/Stormwater Plan was completed. Future revenue, staffing, and equipment needs are identified, and a five year prioritized schedule is presented. The implementation plan is consistent with the City’s NPDES Phase II Municipal Stormwater Permit Application and the Underground Injection Control Rule proposed by the Ecology. ---PAGE BREAK--- Section 3 — Drainage Area Characterization C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-1 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc Description of the Planning Area Description of the Planning Area Description of the Planning Area Description of the Planning Area Location and Boundaries Location and Boundaries Location and Boundaries Location and Boundaries The study area for the Kennewick Comprehensive Stormwater Plan includes the natural and manmade drainage features within the City of Kennewick Urban Growth Area (UGA). Located in southeast Washington’s Benton County, the City of Kennewick is often referred to as one of the “Tri-Cities,” along with the cities of Pasco and Richland. See Vicinity Map presented in Figure 3-1. A map of the City of Kennewick Study Area is included as Figure 3-2. The City’s northern boundary is the Columbia River, which separates Kennewick from the City of Pasco and the unincorporated areas of Franklin County. The third city of the “Tri-Cities” is the City of Richland, located to the west and northwest of Kennewick. Several pockets of unincorporated Benton County reside within the Kennewick city limits and may eventually be annexed into the City. To the northwest of the City, near the Richland city limits, the Yakima River drains into the Columbia River. The Urban Growth Area (UGA) of Kennewick, as shown in the City’s Comprehensive Plan, encompasses about 30 square miles (see Figure 3-2). Currently, about 24 square miles of the City’s UGA are within the City’s corporate boundary, as reported in the City’s National Pollutant Discharge Elimination System Phase II Stormwater Permit Application (NPDES Permit Application) in March 2002. Major roads in and around Kennewick include Highway 240 to the north, Interstate 82 to the southwest, and Highway 395 running northeast/southwest through the middle of the City. Population and Growth Population and Growth Population and Growth Population and Growth Incorporated in 1904, the Northern Pacific Railroad brought slow, but steady population growth to the agricultural community of Kennewick. Kennewick’s population experienced tremendous growth due to World War II and the Hanford Project, as the City grew from a population of 1,900 in 1940 to a population of 10,100 in 1950 (City of Kennewick Comprehensive Plan, 2003). Since then, Kennewick has maintained the largest population of the Tri-Cities, with a 2000 census population of 54,693 people. The Washington State Office of Financial Management (OFM), as part of the Growth Management Act, has provided future population estimates to Benton County Planners that includes the City of Kennewick. The official population forecast for Kennewick is 85,540 in the year 2025. However, the City’s webpage has already reported a population of 60,410 in 2005. ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-2 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc Kennewick’s slow but steady population increase of 3.8% per year is due to a couple of local land use factors. The first is the occasional population spike that shows a direct correlation to federal investments on the Hanford Reservation. The second and predominant source of the City’s increase in population is the periodic annexation of land from Benton County (City of Kennewick Comprehensive Plan, 2003). The City of Kennewick estimates that approximately 5,000 Benton County residents are currently on City water and sewer. Annexing these areas would put Kennewick’s population well above the official OFM forecast. The City of Kennewick’s 2003 Comprehensive Plan estimates a 2012 population closer to 72,000 people. Land Use Land Use Land Use Land Use The City of Kennewick Planning Division performed a land use inventory as part of the development of the City’s 2003 Comprehensive Plan. Land use patterns inventoried within Kennewick’s Urban Growth Area are shown in Figure 3-2. Patterns identified in the 2003 Comprehensive Plan include:
Commercial and industrial areas are located primarily near the Columbia River and railroad lines in the more northern areas of the City. There are 2,347 acres of commercial and industrial designated areas within the City of Kennewick, and 58% of these areas are already developed. Future development of commercial and industrial lands within the City may be limited due to the lack of available space.
Medium and high density (5-27 units per acre) residential areas generally lie south of the commercial and industrial areas. They are located in close proximity to major roads, including Highways 240 and 395. This land type is also limited, as approximately 79% of the City’s 1,907 designated acres in this land use category have already been developed. Limited medium and high-density residential development is expected to increase in the future.
Kennewick has an abundance of available land in the low-density residential land use of four or less units per acre. Low-density residential area occupies the largest amount of area within the urban growth boundary and is primarily located in the southern half of the City. Only 38% of the 10,905 designated acres have been developed.
The percentage of impervious area on a developed parcel of land has generally increased over the last ten years from under 50% to between 75% and 100%. Roadways and parking lots in Kennewick occupy 23% of all developed land. Climate and Rainfall Climate and Rainfall Climate and Rainfall Climate and Rainfall Kennewick has a typical Eastern Washington arid climate. Average temperatures range from 75 to 33 degrees Fahrenheit, with an average maximum of 90º F in July and an average minimum of 26º F in January. Located between the Cascade and Blue Mountains, little rainfall is received in this central desert area. ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-3 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc The average rainfall is 7.6 inches per year. (Climate and rainfall data were obtained from May 2004.) The precipitation events that cause the most concern are of two types, thunderstorms and winter floods. Thunderstorms are high intensity, short duration storms that produce high peak rates of runoff. Thunderstorms are most common in the spring or fall. Winter floods often occur when warmer rains fall on frozen ground. These winter floods are accentuated when the rain triggers rapid snowmelt. Winter floods have smaller discharge peaks than the thunderstorms, however the discharge rates tend to occur for a longer duration than the thunderstorms. Thus, the City’s design criteria are based on both types of storm events. Summer storms are used to size conveyance facilities, and winter storms are used to size detention/retention facilities (if approved by City). Historically, the Kennewick area was routinely subjected to significant flooding. Past major flooding events are well documented in the City’s 1990 Flood/Stormwater Plan (JUB, 1990). However, since the construction of the system of levees and pumps along the City’s northern river waterfront in the 1950’s, the McNary Dam on the Columbia River, and the construction of the Zintel Dam in the mid 1990’s, the risk of future major flooding has been significantly reduced. Topography Topography Topography Topography Within the City of Kennewick, local topography dictates surface hydrology. It also plays a major role in controlling the magnitude and location of local drainage and regional flooding problems. From the Columbia River (at 132 feet above sea level), the elevation within the City steps up to 400 feet above sea level. The majority of Kennewick sits on a plateau that has a relatively flat slope. The plateau is flat enough that the crowns of streets, curbs, and railroad embankments define drainage paths and often define the drainage basins. Toward the southern limits of the City’s GMA, elevation gradually climbs to 600-800 feet, as shown in Figure 3-3. Just outside the southern GMA boundary, the ground slopes increase dramatically and result in elevations reaching 1,100 feet. Natural Drainage Features Natural Drainage Features Natural Drainage Features Natural Drainage Features The City contains 18 major drainage basins, as shown in Figure 3-4. Most of the City drains toward and eventually discharges into the Columbia River, either directly or via the Yakima River. The exceptions are seven basins within the City that act as closed depressions, infiltrating all runoff with no surface water discharges. These seven basins constitute approximately 33% of the land area within the City. The natural characteristics of the area emphasize the importance of infiltration as the primary disposal technique for stormwater within the City. One basin, the Elliot Lake Basin, flows to the southeast via an irrigation canal. ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-4 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc There are few year-round streams or springs present within the study area. Wetland areas are present in the East Amon Basin, along portions of the south shore of the Columbia River, in the Haxton Drain Basin, and in central area of Zintel Canyon within the golf course. Lake features include Elliot Lake in the south upland area of the City, the Frog Pond in the Garfield Canyon Basin, and the Duck Pond, Family Fishing Pond, Duffy's Pond, and City’s wastewater lagoons in the northeast area of the City, adjacent to the Columbia River. Geology and Soils Geology and Soils Geology and Soils Geology and Soils Columbia River Basalt makes up the bedrock that underlies much of Eastern Washington, including the City of Kennewick. Columbia River Basalt consists of many layers of impervious basalt separated by fractured and porous zones that may include sediment material and scattered aquifers. The basalt under Kennewick is approximately 10,000 feet thick (Golder, 1997). The basalt dips toward the Columbia River, allowing groundwater to flow through the porous zones toward the Columbia River. At some locations the basalt is exposed at the surface. Normally, the basalt is not at the surface because it is covered by the upper and lower layers of the Ringold Formation. The upper Ringold Layer is a conglomerate of sand and gravel, and lies above the Lower Ringold Layer. Most of the region’s groundwater resides in this upper layer as an unconfined aquifer. The upper Ringold Layer typically ranges from 20- to 60-feet thick, and is 40 to 50 feet thick where the City’s Ranney wells and #5 are located (Golder, 1997). The Lower Ringold Layer is composed of sand, silt and clay, and acts as a “regional aquitard”. It tends to reduce the hydraulic conductivity between the deep groundwater stored below in the basalt, and the shallow groundwater above (Golder, 1997). The upper layer, composed of flood deposits called the Hanford Formation, is located at the surface and directly above the Upper Ringold Layer. The Hanford Formation is mostly unsaturated because it occurs above the water table. As thin as 20 feet by the Columbia River, the Hanford Formation increases in thickness to as deep as 200 feet in some areas as it moves away in both the north and south direction (Golder, 1997). The Hanford formation includes two types of materials, Pasco Gravels and Touchet Beds. The Pasco Gravels are comprised of coarse grained sand and gravel and cover much of northern Kennewick. The Touchet Beds are located in southern Kennewick and are comprised of fine grained silt and clay. The soil in Kennewick can be further broken down into several different soil types as shown on Figure 3-5. The primary soils types include the Scooteney-Kennewick and ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-5 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc Finley-Burbank-Quincy. Detailed descriptions of these alluvial soils, and other soils lying within the Kennewick Study Area are included in Table 3-1. Table 3 Table 3 Table 3 Table 3-1 Common Soils of the Kennewick Stormwater Study Area Common Soils of the Kennewick Stormwater Study Area Common Soils of the Kennewick Stormwater Study Area Common Soils of the Kennewick Stormwater Study Area Soil Series Soil Series Soil Series Soil Series Description Description Description Description Burbank This series consists of excessively drained, coarse-textured soils on terraces along the Yakima and Columbia Rivers. These soils developed under grass and sagebrush in gravelly and stony alluvial deposits mantled with mixed alluvium and windblown sand. In some places solid basalt bedrock occurs at a depth of about 25 inches. These soils are nearly level to steep. Elevations range from 300 to 800 feet. The annual precipitation is 6 to 8 inches, the mean annual temperature is 53°F, and the frost-free season is about 180 days. Burke This series consists of a well-drained, shallow and moderately deep, medium- textured soils that have a hardpan. These soils occur on uplands midway up the slopes of the Rattlesnake Hills and in the Horse Heaven Hills. They developed under bunch grasses in windblown deposits of mixed origins. In most places they are underlain by basalt bedrock, but in some areas, by very gravelly material. They are gently sloping to steep. Elevations range from 1,000 to 1,300 feet. The annual precipitation is 6 to 9 inches, the mean annual temperature is 50°F, and the frost-free season is about 155 days. Ellisforde This series consists of well-drained, deep, medium textured soils on uplands in the northeastern part of the area. These soils developed under bunch grasses in a mantle of silty, wind-deposited material over lacustrine sediments. They are nearly level to moderately steep. Elevations range from 1,000 to 1,900 feet. The annual precipitation is 9 – 12 inches, the mean annual temperature is 50°F, and the frost free season is about 150 days. Esquatzel This series consists of deep, well-drained, medium-textured, nearly level to gently sloping soils on bottom lands. These soils developed under bunch grasses in alluvium. The areas are generally narrow and are incised by intermittent streams. Elevations range from 300 to 1,400 feet. The annual precipitation is 6 to 12 inches, the mean annual temperature is 50°F, and the frost-free season is about 150 days. Finley This series consists of well-drained, nearly level to steep soils on old alluvial terraces and bottom lands of intermittent streams. These soils are underlain by gravel. They formed under bunch grasses in old alluvial material derived mainly from loess and basalt but partly from granite and quartzite. Elevations on terraces range from 300 to 800 feet. The annual precipitation is 6 to 9 inches, the mean annual temperature is 51°F, and the frost-free season is about 160 days. ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-6 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc Table 3 Table 3 Table 3 Table 3-1 (cont.) 1 (cont.) 1 (cont.) 1 (cont.) Common Soils of the Kennewick Stormwater Study Are Common Soils of the Kennewick Stormwater Study Are Common Soils of the Kennewick Stormwater Study Are Common Soils of the Kennewick Stormwater Study Area Soil Series Soil Series Soil Series Soil Series Description Description Description Description Hezel This series consists of deep, well-drained soils on hummocky or dunelike terraces. These soils developed under grass, sagebrush, and rabbitbrush in a mantle of windblown sand over silty lacustrine sediments. They are gently sloping to steep. Elevations range from 500 to 1,000 feet. The annual precipitation is 6 to 8 inches, the mean annual temperature is 51°F, and the frost-free season is about 155 days. Kennewick This series consists of well-drained, deep, medium-textured soils. These soils developed under bunch grasses in lacustrine material. They are nearly level to steep. Elevations range from 500 to 700 feet. The annual precipitation is 6 to 9 inches, the mean annual temperature is 50°F, and the frost-free season is about 155 days. Kiona The Kiona series consists of well-drained, very stony, medium-textured soils underlain by basalt rubble. These soils developed under bunch grasses in a mixture of windlaid deposits and basalt residuum. Elevations range from 800 to 2,500 feet. The annual precipitation is 7 to 12 inches, the mean annual temperature is 49°F, and the frost-free season is about 145 days. Koehler This series consists of somewhat excessively drained, coarse texture soils on hummocky terraces. These soils formed under grass, sagebrush, and rabbitbrush in a mantle of windblown sand overlaying a lime-silica cemented hardpan. They are nearly level to sloping. Elevations range from 300 to 800 feet. The annual precipitation is 6 to 8 inches, the mean annual temperature is 53°F, and the frost-free season is about 165 days. Pasco These soils are somewhat poorly and moderately well drained; very slow runoff or ponded with moderate permeability. They are found in basins and low flat areas adjacent to the Columbia River and its tributaries. Pasco soils formed in recent alluvium accumulating under ponded drainage conditions. Elevations range from 250 to 700 feet. The annual precipitation is 6 to 10 inches, the mean annual temperature is 54°F, and the frost-free season is 136 to 190 days. Prosser The Prosser series consist of moderately deep, well drained soils that formed mainly in loess and glaciofluvial sediments over basalt. These soils are on hillslopes, benches, and plateaus. Elevations range from 300 to 2,400 feet. The annual precipitation is 6 to 9 inches, the mean annual temperature is 49 to 51°F, the frost-free season is 135 to 210 days. Quincy The Quincy series consists of excessively drained, coarse-texture soils on hummocky or dunelike terraces mainly near West Richland. These soils formed under grass, sagebrush, and derived from granite, basalt, and quartzite. They are nearly level to steep. Elevations range from 300 to 1,100 feet. The annual precipitation is 6 to 8 inches, the mean annual temperature is 51°F, and the frost-free season is about 165 days. ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-7 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc Table 3 Table 3 Table 3 Table 3-1 (cont.) 1 (cont.) 1 (cont.) 1 (cont.) Common Soils of the Kennewick Stormwater Study Area Common Soils of the Kennewick Stormwater Study Area Common Soils of the Kennewick Stormwater Study Area Common Soils of the Kennewick Stormwater Study Area Soil Series Soil Series Soil Series Soil Series Description Description Description Description Scooteney This series consists of well-drained, medium –textured soils on old alluvial terraces and on bottom lands along intermittent streams. These soils developed under bunch grasses in stony and gravelly alluvium and silty, windblown deposits. They are nearly level to steep. Elevations range from 400 to 1,300 feet. The annual precipitation is 6 to 9 inches, the mean annual temperature is 50°F, and the frost-free season is about 150 days. Shano This series consists of well-drained, medium-textured soils. These soils developed under bunch grasses in silty, windblown deposits. They are gently sloping to steep. Elevations range from 500 to 1,300 feet. The annual precipitation is 6 to 9 inches, the mean annual temperature is 50°F, and the frost-free season is about 150 days. Starbuck This series consists of well-drained, shallow, medium-textured soils on terraces. These soils formed under bunch grasses and sagebrush in silty wind-deposited material and in alluvium. They are nearly level to steep. Elevations range from 500 to 750 feet. The annual precipitation is 6 to 9 inches, the mean annual temperature is 50°F, and the frost-free season is about 155 days. Umapine This series consists of moderately well-drained, medium textured, saline- alkali soils on bottom lands. These soils are nearly level. They formed in alluvium under a vegetative cover of wild rye, alkali bluegrass, and greasewood. Elevations range from 250 to 1,000 feet. The annual precipitation is 6 to 9 inches, the mean annual temperature is 50°F, and the frost-free season is about 150 days. Wamba This series consist of somewhat poorly drained, medium-textured soils on terraces. These soils occur in nearly level to depressed areas. They formed in sandy and gravelly alluvium mantled with a mixture of alluvium and silty, windblown deposits. Elevations range from 675 to 775 feet. The annual precipitation is 6 to 8 inches, the mean annual temperature is 50°F, and the frost-free season is about 150 days. Warden This series consist of well-drained, medium-textured soils. These soils developed under bunch grasses in a mantle of windblown deposits over reworked lacustrine material. They are gently sloping to steep. Elevations range from 550 to 1,000 feet. The annual precipitation is 6 to 9 inches, the mean annual temperature is 50°F, and the frost free season is about 150 days. From a stormwater perspective, more important than the soil type are the hydrologic properties of the soils; especially in a region where infiltration is so important. The following hydrologic soil groups are found within the boundaries of the City of Kennewick as shown on Figure 3-6: • Group A Group A Group A Group A includes sand, loamy sand, or sandy loam types of soils. It has low runoff potential and high infiltration rates even when thoroughly wetted. They ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-8 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc consist chiefly of deep, well to excessively drained sands or gravels and have a high rate of water transmission. • Group B Group B Group B Group B is silt loam or loam. It has a moderate to low infiltration rate when thoroughly wetted. Group B soils consist of moderately fine to moderately coarse textures, with a moderate rate of transmission. These are the predominate types of soils that exists throughout the Kennewick Study Area. • Group C Group C Group C Group C soils are sandy clay loam. They have low/slow infiltration rates, and moderately high runoff potential, when thoroughly wetted. Group C consists chiefly of soils with a layer that impedes the downward movement of water, or contains soils with moderately fine to fine structure. • Group D Group D Group D Group D soils are clay loam, silty clay loam, sandy clay, silty clay or clay. Group D has a high runoff potential, with very low/slow infiltration rates when thoroughly wetted. It consists chiefly of clay soils with a high swelling potential, soils with a permanent high water table, soils with a claypan or clay layer at or near the surface, and shallow soils over nearly impervious material. These soils have a slow rate of water transmission. The locations of the Pasco Gravels, Touchet Beds, and surface basalt are shown in Figure 3-7. A profile of these geological layers is included in Figure 3-8. Vegetation Vegetation Vegetation Vegetation Shrubs and forbs are the common types of vegetation found in the City of Kennewick. Dominant shrubs include sagebrush, green rabbitbrush, rose and blackberry. Cattails, bulrush, sedges, horseweed and milkweed are all common forbs. Black Cottonwood, willow and Russian Olive are commonly found near stream channels and wetlands. Vegetation is so dense in areas that it led the City to develop a vegetation control program in 1992. Under this program the City controls vegetation within all street rights-of-way, including curb lines, shoulder rights-of-way, and City property totaling 5,733,637 square feet. The vegetation control program mows areas such as ditch banks, riverbanks, around water reservoirs, wastewater plant and other areas not already controlled by the weed-spraying program due to environmental issues. (JUB, 1990) Groundwater: Regional Drinking Water Sources Groundwater: Regional Drinking Water Sources Groundwater: Regional Drinking Water Sources Groundwater: Regional Drinking Water Sources The City of Kennewick extracts the majority of its drinking water from underground aquifers. While the City is upgrading the Water Filtration Plan (2004-2007) to increase surface water sources, groundwater will continue to be the primary drinking water source for the City of Kennewick. For this reason, the groundwater source is a critical component to the City’s water system and the water quality of the shallow aquifers beneath the City needs to be protected. ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-9 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc Aquifer Layers The groundwater in Eastern Washington has three different aquifer layers that correspond to geological layers. From the most shallow to the deepest, they are the basal Ringold, the middle Ringold, and the basalt. The Kennewick Study Area has only two of these aquifer layers: the middle Ringold layer and the basalt. The deepest aquifers lie in the basalt layer under the City. These aquifers are composed of confined pockets of water, located within the porous areas and fractures of the basalt. Basalt aquifers are not well connected hydraulically because they exist in such low permeability material. However, basalt groundwater does have the ability to flow through the fractures, allowing basalt aquifers to release groundwater upward to more shallow aquifers. The more shallow aquifers in Kennewick are located within the middle Ringold geological layer. These unconfined aquifers are bordered by the water table above, by low permeability basalt below. Laterally, they are in direct hydraulic continuity with the Columbia River (Golder, 1997). Please see Figures 3-7 and 3-8 showing the location and geologic characteristics of a typical geologic cross-section within the Kennewick Study Area. Wells and Treatment Plants Most wells in the Kennewick area draw groundwater from the unconfined aquifer in the middle Ringold layer. This includes drinking water sources for the City of Kennewick, Ranney Collectors 4 and 5. The City’s two wells extend their laterals at depths of 51.7 feet and 41.4 feet, respectively. At these depths, the wells are below the bottom of the Columbia River in the middle Ringold layer. Located in Columbia Park, these two wells were constructed in 1959 and 1960, respectively, to replace the original Ranney Collectors 1, 2, and 3, which have since been abandoned (Golder, 1997). Ranney Collector Wells 4 and 5 are shown with their 10-year protection area in Figure 3-9. On the average, Ranney Collectors 4 and 5 produce 1.0 million gallons of water per day (mgd) and 5.0 mgd, respectively. However, they have the capacity to produce up to 1.2 mgd and 12.8 mgd, respectively. Combined, these two wells have historically provided 60% of the City’s water supply (Golder, 1997). The two Ranney wells can meet the City’s average daily water demand of approximately 9.7 mgd. However, when water demand hits the summer peak of 18 mgd, largely due to irrigation, an additional water source is required. From March through October, the increased demand is met by the City’s Water Treatment Plant which draws an additional 7.5 mgd from the Columbia River (City of Kennewick ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-10 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc Comprehensive Plan, 2003). After completion of upgrades to the City’s Water Treatment Plant (2004-2007), the City will be able to increase production from the plat to 15 mgd. The two Ranney Collectors, however, will remain as the primary water supply source for the City. Groundwater Recharge With aquifers loosing water from leakage to the Columbia River and extraction by wells, groundwater recharge is extremely important to maintaining the water balance within the region’s aquifers. On average, groundwater in the Kennewick study area leaks 103 mgd to the Columbia River and provides 6 mgd to Ranney Collectors 4 and 5 totaling 109 mgd that must be balanced by recharge (Golder, 1997). The primary source of groundwater recharge is seepage from unlined irrigation canals. Irrigation canal seepage supplies aquifers with 41 mgd from the KID canals and 6 mgd from canals north of the Columbia River (Golder, 1997). The canals are a large source of recharge because they are primarily constructed in the highly permeable Pasco Gravels. Pasco Gravels have a variable hydraulic conductivity ranging from 48 ft/day to 73,000 ft/day, with a median of 880 ft/day (Golder, 1997). The second largest contributor to groundwater recharge is the 34 mgd provided by the infiltration of precipitation (Golder, 1997). With so much of Kennewick covered by soils with moderate infiltration rates (1 to 4.5 in/hr), most of the area’s surface water infiltrates. Infiltration from septic systems may also be a source of groundwater recharge. However, because the majority of the City is on a sewer system, septic system recharge is relatively small in comparison. The balance of the recharge water comes from groundwater flowing in from other adjacent aquifers (15 mgd) and the Columbia River (13 mgd) (Golder, 1997). These recharge sources flow through the middle Ringold layer where the hydraulic conductivity ranges from 7.5 ft/day to 5,000 ft/day, with a median of 180 ft/day (Golder, 1997). Aquifers located deep in the basalt may also contribute to groundwater recharge via cracks in the basalt. However, because basalt has such a low permeability, recharge from deep aquifers is very small in comparison. Wellhead Protection Plan While the moderately high to high infiltration rates of City soils are great for infiltrating stormwater and for groundwater recharge, they also pose a potential risk for groundwater contamination. In order to protect the multiple groundwater sources that the City uses as its primary sources of drinking water, the City developed a Wellhead Protection Plan (WHPP) in 1997 to delineate wellhead ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-11 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc protection areas and identify risk within the areas associated with the Ranney Collector Wells #4 and The WHPP defines areas of different levels of wellhead protection based on groundwater travel time. The protection areas are considered conservative in size because they are based on the time travel of groundwater, while contaminants typically travel slower than the groundwater. Even so, buffer zones have been added around these protection areas as an additional precaution. The areas surrounding the two City wells are, however, subject to change. For example, if irrigation canals were lined in the future, their contribution to the groundwater recharge would be reduced. In order to maintain a water balance, the area contributing to the public water may shift (mostly likely toward the Columbia River) and the wellhead protection area may need to be redefined. Within the wellhead protection areas land use is predominantly residential, which is considered a low contamination risk because septic use is limited. High risk commercial and industrial areas are predominantly located within the 0.5- and 1- year time of travel wellhead protection boundaries. Considering that the City requires businesses to infiltrate all stormwater onsite, any onsite contamination will likely infiltrate. The WHPP provides addresses of 169 potential contamination sources within the wellhead protection area and its buffers, with the biggest contributors being automobile service/fueling businesses followed by dry cleaning businesses (Golder, 1997). Contingency Plan The WHPP provides a contingency plan for use in the event of water supply contamination or disruption. The first part of the plan is monitoring the known risks in an attempt to detect potential contaminants before they reach the Ranney well collectors. The WHPP contingency plan also provides water supply replacement alternatives for short term and/or long term implementation. Water supply disruption response procedures, including emergency reporting and public communications, are outlined within the contingency plan along with prevention education and training. Sensitive and Critical Areas Sensitive and Critical Areas Sensitive and Critical Areas Sensitive and Critical Areas There are a number of sensitive and critical areas within the City’s UGA, as shown in Figure 3-9. The types of sensitive areas within the City include wetlands, aquifer recharge areas, 100-year floodplain, buffer/riparian areas, lakes, and rivers. The City of Kennewick protects these areas via its Environmentally Sensitive Areas Ordinance, last updated in 1984. ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-12 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc The highest concentration of wetland areas within the City exists along the shores of the Columbia River and within the Aquifer Recharge Areas, as shown in Figure 3-9. There are nine identified wetlands in Columbia Park that provide year round habitat for geese and ducks, as well as a resting area for White Pelicans during their annual migration (HDR, 1996). Additionally, these sensitive areas provide habitat for bald eagles that have been observed nesting within the large tree stands within Columbia Park. Rearing habitat for juvenile salmonoids is also provided in the near- shore areas of the Columbia River. The 100-year floodplain has nearly been eliminated through the construction of the dams, levees, and pumps along the Columbia River and the large detention dam in the mid-reach of Zintel Canyon. Only a small amount of the 100-year floodplain remains in the north Kennewick area in the Haxton Drain and East Kennewick Basins. Additional critical areas within Kennewick’s UGA other than wetland and floodplains include aquifer recharge areas, riparian areas, open space (UNO) areas, and waterfowl habitat. The UGA also contains agricultural land, which will be developed as the City continues to grow. As part of the City’s Growth Management Plan, a draft ordinance is being developed that will protect critical and agricultural lands from premature development (state law requires the identification of agricultural land in zoning). Generally, there is little habitat value provided within the highly developed areas of the City of Kennewick and along the Columbia River in Columbia Park. However, the larger canyons, such as Zintel, Conway, and the upper reaches of Garfield, continue to support a variety of wildlife species. While the lower and middle reaches of these urbanized canyons are mostly developed, ducks (primarily mallards), frogs, small mammals, and songbirds are still able to find some suitable habitat. In the upper reaches of these canyons, away from the more dense developments, even more species thrive. These species include California quail, mourning dove, ring-neck pheasant, chucker, coyote, badger, striped skunk, mule deer, horned lark, meadowlark, deer mouse, and several different reptiles. (JUB, 1990) Many of the local streams within the City go dry during the summer months, especially as they get farther away from the Columbia River; therefore there is little permanent fish habitat within the City. Smallmouth bass, perch, sculpin, and non- game fish, however, can be found in the reaches closest to the Columbia River (JUB, 1990). No federal or state threatened or endangered species are documented residents of the Kennewick Canyons. However, the peregrine falcon, classified as a candidate species by USFWS, may migrate through in the fall and burrowing owl, a state ---PAGE BREAK--- Section 3 — Drainage Area Characterization Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 3-13 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 3.doc species of concern, may be found nesting within the Study Area. The Swainson’s hawk, ferrunginous hawk, and long-billed curlew are federal candidate species that may occasionally be seen locally as well. (JUB, 1990) Summary of Drainage Area Characterization Summary of Drainage Area Characterization Summary of Drainage Area Characterization Summary of Drainage Area Characterization The Kennewick Comprehensive Stormwater Study Area includes a unique combination of geological, ecological, and surface and groundwater drainage features that are typical of the local arid, Eastern Washington climate. Guidance for developing an effective stormwater program for the City from the above Characterization of the Drainage Study Area includes the need to: • Map soils and locate existing dry well facilities, record designs (as-builts), monitor performance, and retrofit as needed. • Properly locate and design new drywell systems, ensuring the local soils, designs, and construction techniques are adequate to the long-term functioning of the facilities. • Protect remaining habitat and natural drainage features through ordinance, development review process, and construction inspection. Identify and protect by ordinance (law) the City’s natural infiltration areas. Identify/map natural drainage ways and establish buffer areas to accommodate increased drainage from new developments. • Fund and implement the City’s Wellhead Protection Plan, as needed to protect the region’s groundwater supplies. ---PAGE BREAK--- 5 90 82 405 205 90 405 90 82 5 90 90 90 5 5 82 FIGURE 3-1 VICINITY MAP 82   240 STUDY AREA    ---PAGE BREAK--- East Amon Basin Zintel Canyon Cascade Elliot Lake Conway Canyon Zintel Dam Basin Williams Basin Canal Garfield Canyon Sunset Columbia Park Duffy's Pond East Kennewick Haxton Drain Vista Field Steptoe Columbia Center Blvd Edison St. 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W COURT ST W CANAL DR LESLIE RD W A ST E A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST W 4TH AVE S CLODFELTER RD S OAK ST E BOWLES RD W KENNEWICK AVE GAGE BLVD E LEWIS ST E BADGER RD STATE HWY 397 E CHEMICAL DR S OLYMPIA ST E 10TH AVE N 14TH AVE N 4TH AVE N RD 36 N 20TH AVE E FINLEY RD E 27TH AVE W 45TH AVE N KELLOGG ST N EDISON ST S UNION ST N 1ST AVE S GARFIELD ST W COLUMBIA DR E AINSWORTH AVE S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N OREGON AVE N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST KEENE RD N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST S COLUMBIA CENTER BLVD N RD 68 W QUINAULT AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE N WASHINGTON ST S OLYMPIA ST STUDY AREA & LAND USE FIGURE 3-2 Legend Drainage Basins Sensitive_Areas City Bndy UGA Bndy RR_Tracks Zoning Commercial High Density Industrial Low Density Medium Density Open Space Public Lakes and Rivers
  395 Columbia River City of Richland City of Pasco 0 1,250 2,500 3,750 5,000 625 Feet ---PAGE BREAK--- 82   240 US HWY 395 US HWY 12 COLUMBIA PARK TRAIL W 10TH AVE W COURT ST W CANAL DR LESLIE RD W A ST E A ST W CLEARWATER AVE W 27TH AVE S ELY ST S HANEY RD W LEWIS ST W SYLVESTER ST S CLODFELTER RD W 4TH AVE S OAK ST E BOWLES RD E BADGER RD W KENNEWICK AVE GAGE BLVD E LEWIS ST STATE HWY 397 E CHEMICAL DR S OLYMPIA ST N 14TH AVE E 10TH AVE N RD 36 N 4TH AVE N 20TH AVE E FINLEY RD E 27TH AVE W 45TH AVE N KELLOGG ST N EDISON ST E AINSWORTH AVE S UNION ST N 1ST AVE S GARFIELD ST W COLUMBIA DR KEENE RD S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST N OREGON AVE S KELLOGG ST N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST N RD 68 N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST S COLUMBIA CENTER BLVD KENNEWICK AVE W QUINAULT AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S KEYSTONE ST S OLYMPIA ST TOPOGRAPHY Legend Lakes and Rivers City Bndy UGA Bndy Wetlands RR_Tracks Elevation 1340 - 1470 1210 - 1340 1080 - 1210 950 - 1080 820 - 950 690 - 820 560 - 690 430 - 560 300 - 430
  395 Columbia River FIGURE 3-3 0 1,200 2,400 3,600 4,800 600 Feet ---PAGE BREAK--- East Amon Basin Zintel Canyon Cascade Elliot Lake Conway Canyon Zintel Dam Basin Williams Basin Canal Sunset Columbia Park Duffy's Pond East Kennewick Haxton Drain Vista Field Garfield Canyon Steptoe Columbia Center Blvd Edison St. 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W COURT ST W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE E A ST S ELY ST W LEWIS ST W SYLVESTER ST S CLODFELTER RD E BADGER RD W 4TH AVE S OAK ST W KENNEWICK AVE GAGE BLVD E BOWLES RD E LEWIS ST E CHEMICAL DR S OLYMPIA ST STATE HWY 397 N 14TH AVE N RD 36 N 4TH AVE N 20TH AVE KEENE RD E 27TH AVE W 45TH AVE N KELLOGG ST E FINLEY RD N EDISON ST S UNION ST N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE E AINSWORTH AVE N OREGON AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL S RD 28 W 1ST AVE S 1ST ST N NEEL ST N RD 68 S WASHINGTON ST N COLUMBIA CENTER BLVD E COLUMBIA DR S COLUMBIA CENTER BLVD W QUINAULT AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S OLYMPIA ST MAJOR DRAINAGE BASINS Legend Lakes and Rivers Irrigation Canals Army Corps Pump City Bndy RR_Tracks UGA Bndy       Natural Flow Outfalls
0 1,300 2,600 3,900 5,200 650 Feet   395 City of Richland Columbia River FIGURE 3-4 Family Fishing Pond Duck Pond Duffy's Pond WW Lagoons Zintel Dam Elliot Lake City of Pasco ---PAGE BREAK--- 82   240 US HWY 395 US HWY 12 COLUMBIA PARK TRAIL W 10TH AVE W COURT ST W CANAL DR LESLIE RD E A ST W A ST W CLEARWATER AVE W 27TH AVE S ELY ST S HANEY RD W LEWIS ST W SYLVESTER ST S CLODFELTER RD W 4TH AVE S OAK ST E BOWLES RD W KENNEWICK AVE E BADGER RD GAGE BLVD E LEWIS ST STATE HWY 397 E CHEMICAL DR S OLYMPIA ST N 14TH AVE E 10TH AVE N RD 36 N 4TH AVE N 20TH AVE E FINLEY RD E 27TH AVE W 45TH AVE N KELLOGG ST E AINSWORTH AVE N EDISON ST S UNION ST S GARFIELD ST W COLUMBIA DR N 1ST AVE S EDISON ST S 4TH AVE KEENE RD N OREGON AVE W AINSWORTH ST S MORAIN ST N GUM ST S KELLOGG ST N YELM ST E AINSWORTH ST FAIRWAY ST COLUMBIA PARK TRAIL E 1ST AVE N RD 56 S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST N RD 68 N COLUMBIA CENTER BLVD N MORAIN ST S COLUMBIA CENTER BLVD W QUINAULT AVE COLUMBIA CENTER BLVD RD 56 VINEYARD DR BN FR INTER COUNTY BRIDGE S KEYSTONE ST S OLYMPIA ST SOILS - TYPE Legend Lakes and Rivers City Bndy UGA Bndy RR_Tracks SOIL_NAME BURBANK BURKE ELLISFORDE ESQUATZEL FINLEY HEZEL KENNEWICK KIONA KOEHLER PASCO PITS PROSSER QUINCY RITZVILLE RIVERWASH ROCK OUTCROP SCOOTENEY SHANO STARBUCK WAMBA WARDEN WILLIS
0 1,200 2,400 3,600 4,800 600 Feet   395 Columbia River FIGURE 3-5 ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W COURT ST W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE E A ST S ELY ST W LEWIS ST W SYLVESTER ST S CLODFELTER RD E BADGER RD W 4TH AVE S OAK ST W KENNEWICK AVE GAGE BLVD E BOWLES RD E LEWIS ST E CHEMICAL DR S OLYMPIA ST STATE HWY 397 N 14TH AVE N RD 36 E 10TH AVE N 4TH AVE N 20TH AVE KEENE RD E 27TH AVE W 45TH AVE N KELLOGG ST E FINLEY RD N EDISON ST S UNION ST S GARFIELD ST N 1ST AVE W COLUMBIA DR S EDISON ST E AINSWORTH AVE S 4TH AVE N OREGON AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST E AINSWORTH ST FAIRWAY ST E 1ST AVE COLUMBIA PARK TRAIL N RD 56 S RD 28 W 1ST AVE S 1ST ST N NEEL ST N RD 68 S WASHINGTON ST N COLUMBIA CENTER BLVD N MORAIN ST S COLUMBIA CENTER BLVD W QUINAULT AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE N WASHINGTON ST S OLYMPIA ST SOILS -HYDROLOGIC GROUP Legend Lakes and Rivers City Bndy UGA Bndy RR Tracks HYD_GRP A B C D
0 1,250 2,500 3,750 5,000 625 Feet   395 Columbia River FIGURE 3-6 Soils - (Low runoff potential) Soils having high infiltration rates, even when thoroughly wetted, and consisting chiefly of deep, well-to-excessively drained sands or gravels. These soils have a high rate of water transmission. Soils - (moderately low runoff potential) Soils having moderate infiltration rates when thoroughly wetted, and consisting chiefly of moderately fine to moderately coarse textures. These soils have a moderate rate of water transmission. Soils - (Moderately high runoff potential) Soils having slow infiltration rates when thoroughly wetted, and consisting chiefly of soils with a layer that impedes downward movement of water, or soils with moderately fine to fine textures. These soils have a slow rate of water transmission. Soils - (High runoff potential) Soils having very slow infiltration rates when thoroughly wetted and consisting chiefly of clay soils with a high swelling potential, soils with a permanent high water table, soils with a hardpan or clay layer at or near the surface, and shallow soils over nearly impervious material. These soils have a slow rate of water transmission. ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W COURT ST W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE E A ST S ELY ST W LEWIS ST W SYLVESTER ST S CLODFELTER RD E BADGER RD W 4TH AVE S OAK ST W KENNEWICK AVE GAGE BLVD E BOWLES RD E LEWIS ST E CHEMICAL DR S OLYMPIA ST STATE HWY 397 N 14TH AVE N RD 36 E 10TH AVE N 4TH AVE N 20TH AVE KEENE RD E 27TH AVE W 45TH AVE N KELLOGG ST E FINLEY RD N EDISON ST S UNION ST S GARFIELD ST N 1ST AVE W COLUMBIA DR S EDISON ST E AINSWORTH AVE S 4TH AVE N OREGON AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST E AINSWORTH ST FAIRWAY ST E 1ST AVE COLUMBIA PARK TRAIL N RD 56 S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST N RD 68 N COLUMBIA CENTER BLVD N MORAIN ST S COLUMBIA CENTER BLVD W QUINAULT AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE N WASHINGTON ST S OLYMPIA ST SENSITIVE AND CRITICAL AREAS FIGURE 3-9 Legend Ranny Wells Lakes and Rivers City Bndy UGA Bndy Wetlands Aquifer_Recharge 100_yr_Flood_Plain RR_Tracks Layer Riparian Border Riparian Hatch Shrub-steppe border UNO Border Waterfowl border
0 1,300 2,600 3,900 5,200 650 Feet   395 Columbia River 10 Year Protection Boundary Note: 10 year Protection Boundary shown for Aquifer Recharge is from Figure 22 of 1997 Golder Associates Wellhead Protection Plan prepared for the City of Kennewick. ---PAGE BREAK--- Section 4 — Existing Stormwater System C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-1 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc City’s Existing Drainage System: An Overview City’s Existing Drainage System: An Overview City’s Existing Drainage System: An Overview City’s Existing Drainage System: An Overview The City of Kennewick Public Works Department manages and maintains the City’s drainage facilities. In their National Pollutant Discharge Elimination System Phase II Stormwater Permit Application (NPDES, 2002), the City estimated 4,200 catch basins in a network of 83 miles of piped storm sewers and open ditches, and three regional outfalls to the Columbia River. Incorporated within this regional drainage system, the City owns and operates an additional 2,000 public infiltration facilities (drywells), and associated inter-conveyance pipes, that accept about 75 percent of the area’s surface water discharges (Staff interview, 2003, and NPDES, 2002). The City’s drainage system also contains one local detention pond, three local retention facilities, and four regional stormwater detention/water quality treatment facilities. The City currently has few water quality treatment facilities (NPDES, 2002). The City-owned surface water facilities are complemented by numerous onsite infiltration facilities constructed by the landowners of commercial developments, private streets, and residential developments. Although these facilities are privately maintained, their drainage is inevitably connected with the City’s system during storm events above the 10-year return interval and during private facility failures. In addition to City owned facilities, several major drainage facilities owned and operated by the Army Corps of Engineers (Corps), including: • About six to seven miles of levees along the south shore of the Columbia River (Lake Wallula), • Stabilization of the level of Wallula Lake through operation of McNary Dam, • The Zintel Dam, and • A regional pump station at Duffy’s Pond. Benton County also operates the Elliot Lake detention facility that currently lies within the City’s Urban Growth Boundary (UGA). The drainage system is laced with three to four tiers of irrigation canals, extending for about 38 miles throughout the study area. These are owned and operated by two major irrigation districts: the Kennewick Irrigation District (KID), and the Columbia Irrigation District (CID). They are historically and currently integrated with the City’s regional drainage and water supply systems. Functionally, these canals provide regional detention during high rainfall events, by collecting excess surface water runoff when the capacity of local drywell system is exceeded. Operating in this manner, they help prevent localized flooding throughout the City. They are also responsible for a substantial amount of local recharge, through canal seepage, to the groundwater aquifers that sustain the City’s two drinking water wells along the south shore of the Columbia River (Ranney Wells #4 and # 5) (Golder, 1997). ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-2 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc Major Drainage Basins Major Drainage Basins Major Drainage Basins Major Drainage Basins In the City of Kennewick, almost all surface water infiltrates into the ground via drywells. However, during peak rainfall events, the intensity of rain falling occasionally exceeds the infiltration capabilities of the ground, resulting in localized surface water runoff (sheet flow). When this occurs, stormwater is at the mercy of topography. Where the topography is flat, surface flows are ultimately directed by streets, gutters, open channels, railroad ditches and other manmade modifications within the eighteen drainage basins that constitute the Study Area. Where the topography is steep — in the canyon areas in the southern portions of the City — surface flows follows the natural drainage paths. The following paragraphs summarize the surface hydrology and general flow patterns within each major drainage basin within the Kennewick UGA. Descriptions follow a general west to east location of basins. See Figure 4-1 for drainage basin locations and boundaries. Steptoe Steptoe Steptoe Steptoe Basin Basin Basin Basin The Steptoe Basin is a residential area in northwest Kennewick serviced by drywells and contains approximately 152 acres. There is very little surface runoff from overtopping drywells. In the event that drywells do overtop, surface water ponds in the ditches along the railroad embankment until it infiltrates. This basin is a closed depression. Sunset Sunset Sunset Sunset Basin Basin Basin Basin The Sunset Basin is just south of the Steptoe Basin in the northwest corner of Kennewick, and contains approximately 646 acres. Sunset surface water follows topography and sheet flows to the northeast corner of the basin, where it is collected in the Mall retention/detention facility. The Mall facility is privately owned. This basin is mostly a closed depression except during high flows when water leaves the facility via an emergency outfall culvert to a ditch along the railroad. Flow travels northwest, crossing under the railroad via a culvert and into the City of Richland conveyance system. The Richland system routes water north, where it eventually discharges into the Columbia River. Columbia C Columbia C Columbia C Columbia Center Boulevard enter Boulevard enter Boulevard enter Boulevard Basin Basin Basin Basin The multi-family/commercial Columbia Center Boulevard basin is filled with apartment buildings outside of the major arterial. After completion of the Kennewick Park Subdivision capitol improvement project, runoff from the basin previously titled Kennewick Park Subdivision in the 1990 Flood/Stormwater Plan was diverted into the Columbia Center Boulevard Basin. The total basin area is now 407 acres. The elevation of Columbia Center Boulevard is such that much of the ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-3 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc surface flow stays east of the boulevard. Surface water flows north through a manmade system to the Columbia Center regional retention/detention facility. This basin is mostly a closed depression except during high flows when water backs out of catch basins and flows into State right of way along Highway 240. Surface water may eventually cross Highway 240 and flow through the WSDOT’s conveyance system and eventually to the Columbia River. Vista Field Vista Field Vista Field Vista Field Basin Basin Basin Basin The Vista Field Basin contains approximately 540 acres of commercial and residential development, as well as the Vista Field Airport in the most southern area of the Basin. Most of the stormwater in this basin infiltrates. Remaining surface water is contained by the higher elevations of West Canal Drive to the north, and the railroad to the south. This basin is a closed depression under normal flow events, with water exiting the basin through infiltration. Edison Street Edison Street Edison Street Edison Street Basin Basin Basin Basin This small basin, located in the northern part of the City, contains approximately 122 acres. When drywells in this basin overtop, surface water flows north and spills into the railroad right of way. Water flows east along the railroad embankment to a culvert that goes under the railroad and Highway 240 into the Duck Pond in Columbia Park. Water leaves the Duck Pond through a discharge channel to the Columbia River. Columbia Park Columbia Park Columbia Park Columbia Park Basin Basin Basin Basin The Columbia Park Basin is a strip of land north of the City that is located along the southern shoreline of the river containing approximately 1052 acres. The area is owned by the Corps, and is leased from the Corps by the City. Surface water in this basin generally sheet flows into the Columbia River. There are three discharges to the Columbia River in the Columbia Park Basin, not including the Duck Pond or Family Fish Pond. One of those discharges contains City runoff from the Williams Basin. Potential water quality issues exist with the adequacy of pollutant removal in the park ditch and combined pollutant loading from the Highway. Williams Basin Williams Basin Williams Basin Williams Basin The 1,511 acre Williams Basin contains numerous drywells with tightlined overflows that convey water to the intersection of Volland St. and Canal, the underpass section of the BNSF railroad. Many of the pipes, however, are undersized and cause local flooding in the Canal Drive underpass under the railroad. Local flooding is contained within the basin by the raised elevations of surrounding streets and railroad embankments. A deep storm mainline conveys water north from the Volland Street/Canal Drive intersection to a discharge north of the irrigation canal that parallels the railroad and Hwy 240. This discharge eventually routes to the ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-4 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc north through culverts and WSDOT Right of Way to a vegetated ditch inside Columbia Park prior to discharging into the Columbia River. East Amon East Amon East Amon East Amon B B B Basin asin asin asin The Amon Creek Basin is located mostly outside of the City Limits and Urban Growth Boundary. Surface water sheet flows to the northwest into the lower reaches of Amon Creek. Amon Creek is a sensitive area that has significant environmental concerns associated with it. The study area for the City of Kennewick is focused on a smaller tributary basin of approximately 1,500 acres located within the UGA. This portion is seasonally fed water from the KID irrigation canal headwater and has been often called the Amon Wasteway. This East Amon Basin is very flat (about 1% slope) compared to the steep slopes located to the south. The East Amon Basin generally drains from east to west into Amon Creek. Amon Creek flows north through a series wetlands, into the City of Richland. Within the City of Richland, the wetlands discharge into the Yakima River, just before its confluence with the Columbia River. Conway Canyon Basin Conway Canyon Basin Conway Canyon Basin Conway Canyon Basin Located in the middle of Kennewick, the large area delineated as the Conway Canyon Basin generally drains from west to east, and contains approximately 2,582 acres. Ultimately surface water runoff flows to the northeast corner of the basin, under State Route 395, and into the golf course ponds. From the golf course ponds, water flows under the irrigation canal and under Highway 240 into the Family Fishing Pond in Columbia Park. A gravity outlet channel connects the Family Fishing Pond to the Columbia River. Canal Canal Canal Canal Basin Basin Basin Basin The Canal Basin is approximately 605 acres. Surface water that does not infiltrate in the Canal Basin sheet flows to the north where it is contained by the higher elevation of West Canal Drive. Surface water flows to the east along Canal Drive and under the irrigation canal and Highway 240. Flows combine with runoff from the Conway and Zintel Canyon Basins to enter the Family Fishing Pond in Columbia Park. Water leaves the Family Fishing Pond through a gravity outlet channel to the Columbia River. Zintel Zintel Zintel Zintel Dam and Zintel Dam and Zintel Dam and Zintel Dam and Zintel Canyon Basin Canyon Basin Canyon Basin Canyon Basins The Zintel Dam, built in the early 1990’s, holds back the sheet flow from the nearly 28 square miles in the Zintel Dam Basin (JUB, 1990). The Zintel Canyon Dam releases water into the Zintel Canyon Basin at a controlled and constant rate. The Zintel Canyon Basin contains approximately 3,380 acres of land. The runoff from the upper canyon joins flows released by the Dam via a culvert under Highway 395. of the Dam, the Zintel Canyon Basin has a ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-5 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc developed storm drainage system that conveys water north to 7th Avenue where the flow enters a 78-inch diameter storm pipe conveying water to West Kennewick Avenue and the Tri-City Country Club. Water then joins the drainage from the Conway Canyon Basin in the golf course ponds. From the golf course ponds, water flows as described in the Conway Canyon Basin to the Family Fishing Pond and discharges into the Columbia River. Duffy’s Pond Basin Duffy’s Pond Basin Duffy’s Pond Basin Duffy’s Pond Basin Duffy’s Pond is a small basin, approximately 732 acres, within the northern part of the City that includes commercial and residential areas in the central business district. Surface water in the Duffy’s Pond Basin collects in Duffy’s Pond. From Duffy’s Pond, the Corps pumps water over the levee and into the Columbia River. The levee pumping system is described in detail below. Garfield Canyon Basin Garfield Canyon Basin Garfield Canyon Basin Garfield Canyon Basin The Garfield Canyon Basin is approximately 1,597 acres. The basin’s conveyance system is comprised primarily of ditches that flow into the existing regional facility north of Park Middle School, commonly known as the Frog Pond. This reservoir infiltrates the basin’s stormwater and has rarely been known to overflow into neighboring basins. Garfield Canyon is considered to be a closed depression. Recently, the City has piped the discharge from the Columbia Rancho subbasin, a subbasin delineated in the 1990 Flood/Stormwater Plan, directly into the Garfield Canyon Basin via a conveyance line in Olympia Street. Elliot Lake Elliot Lake Elliot Lake Elliot Lake Basin Basin Basin Basin Surface water in this 2,500 acre basin flows northeast to Elliot Lake. Elliot Lake is within the City’s GMA, but outside of the current City limits. Water leaves Elliot Lake via a ditch and enters into an irrigation canal flowing to the southeast. Some of the surface water from Elliot Lake is thought to join drainage surrounding Bowles Rd surface water via a ditch, flowing to the southeast away from the City. Cascade Basin Cascade Basin Cascade Basin Cascade Basin The Cascade Basin is a large flat depression, containing approximately 1,734 acres, with very good soil for infiltration. The Cascade Basin generally consists of an upper and lower region. The upper region is located on the plateau where surface water is directed towards a canyon that parallels Cascade Street. The majority of water conveyed down the canyon is intercepted by the irrigation canal near the intersection of Washington Street and West 27th Avenue. In the lower region, the runoff is generally directed south towards the same intersection. The 1990 Flood/Stormwater Plan recommended constructing a regional retention facility at South Gum Street and East 27th Avenue. This project is not currently planned for construction. After improvements to Washington Street, the smaller East 23rd ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-6 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc Avenue retention/detention facility was constructed to collect surface run-off from the widened and reconstructed road project. Elsewhere in the lower region, surface water collects in shallow localized depressions throughout the basin where it infiltrates. The Cascade Basin is mostly a closed depression. However, some surface water collected by the irrigation canals flows out of the basin to the southeast. East Kennewick Basin East Kennewick Basin East Kennewick Basin East Kennewick Basin The East Kennewick Basin, located in northeast Kennewick, generally consists of light industrial/commercial areas with some older residential neighborhoods. The basin contains approximately 883 acres. Its existing piped storm system generally drains from south to north, and ultimately discharges to Duffy’s Pond where it is pumped by the Corps into the Columbia River. Haxton Drain Basin Haxton Drain Basin Haxton Drain Basin Haxton Drain Basin The Haxton Drain Basin is a 686 acre basin located in the northeast corner of the City of Kennewick. In this basin, surface water flows generally towards an open channel canal (the Haxton Drain) that bisects the basin traveling west to northeast towards the existing Corps Ditch on the south side of the Columbia River levee. There is no visible discharge from this basin. Infiltrated water ultimately finds its way into the Columbia River, just to the north, via shallow groundwater. This basin also contains the Wastewater Treatment Plant lagoons which do not affect the storm run-off. Manmade Drainage Features Manmade Drainage Features Manmade Drainage Features Manmade Drainage Features Manmade drainage features compliment and work in concert with the natural drainage features described above. As described in the City’s March 2003 NPDES II permit application, the manmade features consist of: • Five regional retention/detention facilities for the control of peak runoff (Family Fishing Pond, Duck Pond, Duffy’s Pond, the Frog Pond, and Elliot Lake), • One regional detention facility to attenuate flows in Zintel Canyon (Zintel Dam), • Five onsite local retention/detention ponds to attenuate peak flows at various locations throughout the City (Clearwater, Columbia Center, Columbia Center Mall, Golf Course Ponds, and East 23rd) • Approximately 4,200 catch basins to collect, concentrate, and direct sheet flows, • Nearly 83 miles of pipes, swales, and ditches for conveyance, • 2,000 drywells for stormwater infiltration, and • Five outfalls where City stormwater occasionally discharges into the Columbia River (three in Columbia Park, Family Fishing Pond, and Duffy’s Pond). The above collection of manmade drainage facilities are graphically displayed in Figure 4-2, with the exception of the drywells, which are shown in Figure 4-3. ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-7 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc Regional Detention / Water Quality Treatment Facilities Regional Detention / Water Quality Treatment Facilities Regional Detention / Water Quality Treatment Facilities Regional Detention / Water Quality Treatment Facilities Retention/Detention (R/D) facilities collect, control, dispose, and treat regional stormwater runoff. These facilities reduce peak runoff rates by detaining water and controlling the flow of water that is released. They also assist in the disposal of water by allowing infiltration and/or evaporation. In addition to reducing peak runoff rates, a vegetated R/D pond can provide water quality treatment by filtering out contaminants, including particulates and oil. If adequate parcels of land are available, R/D facilities may also attenuate peak flows in a way that may reduce the need for large diameter and expensive conveyance pipes in reaches of heavily developed basins. The City of Kennewick benefits from the operation of ten regional and/or local detention and water quality treatment facilities, as shown in Figure 4-2. Each of the facilities is described below: • The Family Fishing Pond, located in the Columbia Park Basin, is one of the City’s largest regional facilities. It accepts regional runoff from several watersheds within the City, including Canal, Conway Canyon, and Zintel Canyon. It gravity discharges directly to the Columbia River. According to Washington Department of Fish and Wildlife (WDFW) HPA (ST 6641-01), all Zintel Canyon flows shall be routed to the Columbia Park Pond year round, except during high water events. Sedimentation is provided upstream of the Family Fishing Pond in a large settling structure in the Tri-City Country Club Golf Course. Runoff from Conway Canyon and Zintel Canyon receives water quality treatment through vegetated flow areas in those basins. A potential pollution source for the discharge may be fertilizer and chemical treatment runoff from the Golf Course and potential pollutants in irrigation water that combines with the Family Fish Pond discharge. • Duck Pond, located towards the west end of Columbia Park accepts run-off from Highway 240, irrigation tailwater, and various other discharges from residential land use to the south. The pond does provide a relatively shallow water body to encourage biological uptake of nutrients and sedimentation of solids prior to discharge into the Columbia River. • Duffy’s Pond, located behind the Corps Columbia River levees, collects much of the surface drainage from the interior of the City, including drainage from the Duffy Pond and East Kennewick Basins. It is fed by large regional drainage ditches that run along the inside of the levees built by the Corps. The discharge from this regional facility is a system of pumps routinely operated by the Corps. Duffy’s Pond provides limited water quality treatment through subsurface infiltration and a long residence time to encourage the sedimentation of suspended solids. • The Frog Pond is the ultimate discharge/disposal point for all surface water ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-8 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc runoff collecting within the Garfield Canyon Basin. No overland discharge has been observed leaving the facility. Prior to entering the Frog Pond, surface water flows through a 900 LF grass lined drainage swale that provides bio-filtration pollutant removal. The treatment capacity is somewhat diminished due to the lack of a high flow bypass and several cross-connections with irrigation canals. The Frog Pond also receives untreated runoff from surrounding high density areas, which typically have higher pollutant loading. The Frog Pond is a relatively deep retention facility, so predicted groundwater elevations in the vicinity that do not provide acceptable vadose zone treatment. • Elliot Lake, located within the City’s UGA in Benton County, is a regional facility that collects and treats regional surface water runoff. The discharge from this facility is thought to enter local irrigation canal and/or be discharged into a ditch to the east along Bowles Road. Like Duffy’s Pond, Elliot Lake provides a significant level of water quality treatment through sedimentation and nutrient removal through the long residence time of water. • Zintel Dam acts as a large regional detention facility. It attenuates the peak flows from the upper reaches of Zintel Canyon and protects the reaches from flooding, erosion, and property damage. Due to the surrounding soils and geology, and relatively short detention times, this facility provides little retention/disposal of collected surface water through infiltration. However, once of the dam, surface water travels an extended distance through natural vegetation, wetlands, and sensitive areas prior to entering the Corps inlet structure at 7th Avenue and Vancouver Street. The waterway is not considered a fish bearing stream and most likely provides a significant level of pollutant removal. • The Clearwater Retention/Detention Facility accepts drainage runoff from Clearwater Ave. within the Amon Wasteway Basin. Discharge enters the Amon Wasteway and the City of Richland to the west, and flows into the lower reaches of the Yakima River, near the junction of the Columbia River. • The Columbia Center Regional/Detention Pond is located in the Columbia Center Boulevard Basin. Its discharge, when it has a discharge, passes under the irrigation canal and Highway 240 to the north into the City of Richland, and likely infiltrates into the Columbia River. The pond has been designed to provide treatment for water quality storms. Overflow from this facility contains very little untreated runoff. • The Mall Retention/Detention Facility is private facility built by the Columbia Center Mall to manage its local drainage. It is the ultimate discharge point for all surface water runoff within the basin. This basin rarely has a discharge and is considered to be a closed depression. • The East 23rd Retention/Detention Facility is located within the Cascade Canyon Basin. This facility accepts surface run-off from a large portion of Washington St. The Basin is a closed depression, with no visible surface water discharge. ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-9 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc Collection System (Catch Basins) Collection System (Catch Basins) Collection System (Catch Basins) Collection System (Catch Basins) Catch basins are used to collect runoff from streets and direct the stormwater to conveyance and/or discharge points via pipes and/or ditches. They often provide some water quality treatment by allowing the heavier particulate matter to settle out before being conveyed. The City of Kennewick requires the uses of catch basins to keep water off of road surfaces, to enhance the longevity of the road surface and subgrade, and to improve the safety of its driving citizens. The City currently owns and operates over 4,200 catch basins throughout the City, as shown in Figure 4-2. Maintenance is routinely provided by City crews, primarily in the form of sediment removal, on a pre- determined priority and frequency. Conveyance Systems (Pipes and Ditches) Conveyance Systems (Pipes and Ditches) Conveyance Systems (Pipes and Ditches) Conveyance Systems (Pipes and Ditches) Pipe and ditch conveyance systems are used throughout the City to provide for the gravity conveyance of surface water runoff. Ditches serve the dual purpose of both infiltrating and conveying surface water, but require culverts at street crossings. The City has over 83 miles of ditches and piped drainage systems, as noted in the City’s Notice of Intent to Ecology (March, 2002). Many of the pipe systems in Kennewick are thought to be undersized and are the subject of modeling and routing studies presented in this report. Solid pipes are shown as solid lines on Figure 4-2. Generally, pipes are used for conveyance along city streets with curbs and sidewalks, while ditches are used for stormwater conveyance along streets that do not have curbs and catch basins. The hydraulic capacity of a pipe or ditch system is compromised when it fills with sediment. Routine inspections and regular maintenance are critical to assuring long-term performance. Discharge Discharge Discharge Discharge System (Drywells) System (Drywells) System (Drywells) System (Drywells) Drywells are the primary method of discharge of stormwater runoff within the City of Kennewick. They have historically been used for managing the drainage from both public and private developments. The City of Kennewick has located, mapped, and recorded the location and condition of over 2,000 drywells within its public drainage system. Drywells are reported in the City’s Notice of Intent to Ecology (March, 2002) as receiving and disposing of the stormwater discharges from over 75% of the City. Mapped drywells are shown in Figure 4-3. According to the City’s stormwater design standards, drywells are designed as perforated concrete structures surrounded by drainage rock and filter fabric. Drywells range in depth from a minimum of nine feet to as deep as required to penetrate pervious strata. Some drywells in the Kennewick may be up to 30 feet ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-10 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc deep (JUB, 1990). The lifetime of a drywell is highly variable, and is directly dependent on the adjacent soil and land use characteristics. The accumulation of sediment quickly reduces the infiltration capacity of drywells. As with catch basins and conveyance systems, routine inspection and regular maintenance are critical for long-term effectiveness. The City routinely cleans its drywell systems and removes sediment. Regional Outfalls and Discharges Regional Outfalls and Discharges Regional Outfalls and Discharges Regional Outfalls and Discharges The City of Kennewick operates five major regional outfalls to the Columbia River and one to the Amon Creek. The Columbia River outfalls include: • The three discharges from the wetland system in Columbia Park that accepts the excess surface drainage from the northwest corner of the City, prior to discharging it into the Columbia. One of these discharges also conveys water from the Duck Pond, • The discharge from the Family Fishing Pond that accepts surface discharges from four of the City’s largest interior basins (Canal, Conway Canyon, and Zintel Canyon), and • The discharge from Duffy’s Pond, which is the pumped discharge from the Corps facility that drains two heavily developed basins within the northern part of the City, the Duffy’s Pond and East Kennewick Basins. These outfalls discharge stormwater runoff from within the City to the Columbia River during high flow events. While over 75 percent of the surface water from within the City infiltrates via the citywide system of drywells, there is on occasion, enough rainfall and/or snow melt to cause require surface water discharges. Most of this water collects in the Duck Pond and Duffy’s Pond, where it is disposed of directly into the river. The locations of these outfalls are shown in Figure 4-2. The outfalls from Columbia Park are shown as storm lines in Figure 4-2 and as trunklines in Figure 4-3. The Amon Creek outfall accepts drainage from the Amon Creek Basin partially located in the City. Much the Basin is undeveloped; however, pressure from residential growth is slowly pushing south and southwest into the drainage basin. Additionally, City zoning has allocated a substantial area around the I-82 and Clearwater Avenue interchange for commercial development and recently amended the City Comprehensive Land Use Plan to include the “Southridge Master Plan” that straddles the East Amon Basin and Zintel Canyon Basin. Zintel Canyon Dam Zintel Canyon Dam Zintel Canyon Dam Zintel Canyon Dam The 90-foot high Zintel Dam provides flood detention for runoff from the upper Zintel Canyon Basin, and releases stormwater at a controlled rate through the 4,160 linear feet of 72-inch storm drain known as the South Rainier Pipeline (JUB, 1990). ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-11 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc Construction of the pipeline was recommended in the 1990 Flood /Stormwater Plan. This project, costing over $9M, was completed with assistance from the Corps Matching in-kind funds ($1.57M) were provided by the City for the construction of the Rainier Conveyance System. The project eliminated the use of West 7th Avenue as an open channel and reduced the potential for flooding, erosion, sedimentation, and substantial damage to the City (JUB, 1990). Levees and Pump Levees and Pump Levees and Pump Levees and Pump In order to protect the Cities of Kennewick and Pasco, the Corps constructed a system of levees, ditches, and a pump system in 1952. In both Kennewick and Pasco, sections of the Columbia and Yakima Rivers are lined with levees. There are approximately three miles of levee within the City of Kennewick. The levees run along the Columbia River from the east end of the Haxton Drain Basin to the Highway 240/395 interchange near the Family Fishing Pond, as shown in Figure 4- 1. The levees are backed with large drainage ditches that drain to a large regional pumping facility located on the northeast corner of Duffy’s Pond (Golder, 1997). The Corps pumps the collected surface water runoff from within the City of Kennewick directly into the Columbia River. The City of Kennewick has recently lowered the top of the levee by approximately six feet for the majority of the length. The open ditch has been piped and partially filled from the Blue Bridge (SR-395) to Clover Island Drive (Duffy’s Pond). This improves the aesthetics in the area and is not expected to change the levee’s basic structure or function. Irrigation Canals Irrigation Canals Irrigation Canals Irrigation Canals The yards and farms in Kennewick’s arid climate require irrigation to survive the summers. Two irrigation districts, the Columbia Irrigation District (CID) and the Kennewick Irrigation District (KID), maintain canals that deliver irrigation water from the Yakima and Columbia Rivers to a service area of approximately 55,000 acres (Golder, 1997), including areas within the City of Kennewick. Irrigation water flows through the canals throughout the irrigation season, which is from April 15 through October 15 (Staff interviews, 2003). The irrigation canals draw water from the Yakima River and generally flow from west to east. They are constructed in tiers such that any spills or runoff of water from one canal is re- collected by the next lower canal system. An estimated 38 miles of irrigation canals are present within the City of Kennewick, as shown in Figure 4-1 through 4-4. Canal seepage and infiltration are common issues. Irrigation water is often applied at a rate that results in rapid groundwater recharge. The canals are generally unlined (although some are lined with concrete or PVC), allowing direct infiltration into shallow groundwater. Canal seepage is evident during the irrigation season by ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-12 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc high groundwater levels and localized surface ponding. This contributes to localized flooding during larger storm events (Golder, 1997). Additional information concerning the interaction between the City’s drainage system and the irrigation canals is presented with the drainage problem areas discussion later in this section. Complaints and Documented Drainage Problems Complaints and Documented Drainage Problems Complaints and Documented Drainage Problems Complaints and Documented Drainage Problems Major Flooding Areas Major Flooding Areas Major Flooding Areas Major Flooding Areas Despite its arid climate, the City of Kennewick can experience seasonal flooding. When winter delivers a combination of rain, snow, frozen ground, and warm Chinook winds, the result is often flooding on a regional scale. The City can also experience flooding from short duration, high intensity summer storms. Prior to the construction in 1992-94 of the Zintel Dam and construction of the dams and levees along the Columbia River, the City was subjected to serious flooding that caused substantial damage to public and private structures. The seasonal flooding associated with the Columbia River was curtailed with the construction of the McNary Dam (Wallula Lake) on the Columbia River in 1952. Since the construction of the dam, additional levees and pump stations have been constructed along the south shore of the river, providing further flood protection. The levees and pump also collect and discharge local stormwater runoff that collects from within the City and discharges it directly into the Columbia River. Major Maintenance Areas Major Maintenance Areas Major Maintenance Areas Major Maintenance Areas When the City receives calls from the public related to flooding throughout the City, the calls are recorded, mapped, and prioritized according to the City’s 1 – 5 priority rating system. Level 5 complaints are the most serious, requiring immediate response (City Staff, Personal Communication, 2004). At present, the City maintains a “trouble list” of addresses of drywells that they regularly maintain during large rain events. Many of these drywells drain so slowly that they tend to backup, forming localized ponds during larger storm events. As the City continues to implement the drywell retrofit program, recommended in the 1990 Flood/Stormwater Plan, many if not all of these local problem areas are expected to be eliminated. The locations denoted with a are funded projects to be eliminated during the completion of this report. These areas are not included in Figure 4-4. 1. 6050 West 20th Avenue 2. 4th Place and Buchanan St. * 3. 4th Place and Buchanan Place * 4. 4th Place and Cleveland St. * 5. 4th Avenue and Buchanan * 6. 4th Avenue and Dawes St. * ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-13 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc 7. 2nd Avenue and Arthur St. 8. 3rd Avenue and Ledbetter St. 9. Yelm St. and Bruneau Avenue 10. Albany St. and Clearwater Avenue Capital Projects Capital Projects Capital Projects Capital Projects The City of Kennewick’s existing 1990 Flood/Stormwater Plan established a capital improvement plan (CIP) to address major flooding throughout the City. The CIP Prioritization Matrix (JUB, 1990, page 9 – 8) contains recommended CIPs. Some of the CIPs have been completed, others are in progress, and some have not been started. The CIPs from the 1990 Flood/Stormwater Plan are listed below in Table 4- 1 and shown in Figure 4-5. The costs from the 1990 report have not been updated. Table 4 Table 4 Table 4 Table 4-1 Capital Project Prioritization Matrix (JUB, 1990) Capital Project Prioritization Matrix (JUB, 1990) Capital Project Prioritization Matrix (JUB, 1990) Capital Project Prioritization Matrix (JUB, 1990) # Project Project Project Project Location Location Location Location Estimated Cost Estimated Cost Estimated Cost Estimated Cost Status Status Status Status 1 South Rainier Pipeline (Zintel Dam) S. Vancouver St. to W. Kennewick Ave. $1,570,000 ($9,285,000) Complete 2 Kennewick Park Subdivision West Kennewick $100,000 Complete 3 Drywell Replacement & Interconnection Primarily South Kennewick $100,000 Ongoing 4 Conway Pipeline SR 395 to N. Yelm St. $100,000 70% Complete 5 Garfield Pipeline West 21st Ave. to West 10th Ave. $167,400 Under Design 6 Gum St. Retention Reservoir Gum St. and 27th Ave. $25,000 Funded The Zintel Dam and its associated South Rainier Pipeline Projects were constructed in 1992-1995, with grant and design support from the Corps. These were the City’s highest priority capital projects. Their construction by the Corps has substantially reduced the risk of major flooding throughout Zintel Canyon and the northern parts of the City along the Columbia River. The Kennewick Park Subdivision and Drywell Replacement & Interconnection projects modify failed drywells that are causing localized flooding. Both of these projects involve the replacement of failing drywells in areas suitable for infiltration. Failing drywells in areas unsuitable for infiltration are connected via short conveyance pipes to functioning drywells or natural drainage channels. These projects reduce the potential for localized flooding and lessen the demand on maintenance crews during major runoff events. The work at the Kennewick Park Subdivision has been completed. The drywell retrofit construction will need to be phased in over the next several years. ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-14 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc The Conway Pipeline project is 70 percent finished. The project involves securing permission to construct dikes around a school playfield, and use the resulting pond as a regional detention facility during large storm events. The dikes will provide a storage area for the volume of stormwater that exceeds the capacity of the existing open channel (ditch) and associated pipeline during major runoff events (JUB, 1990). When constructed, the Garfield Pipeline will replace an open channel conveyance system with 3,200 lineal feet of storm drain sized from 39 to 48 inches in diameter. This existing open channel is located next to a school and is considered a potential hazard to human safety during large storm events (JUB, 1990). Additional capitol projects identified through HDR’s detailed hydrologic and hydraulic modeling are presented in Section 7. Water Quality Water Quality Water Quality Water Quality Little is known about the general water quality of the surface water runoff that occurs throughout the greater Kennewick Stormwater Planning Area (City’s Urban Growth Area). There is little water quality monitoring data and no regular monitoring program conducted by the City, the Corps, public health, the irrigation districts, the county, or any other agency or local group. With only four to seven inches of total rainfall, including snow and dew, there is very little runoff to monitor during much of the year. No local water bodies within the City of Kennewick are on the State’s 303(d) List of Impacted Water Bodies. The Columbia River, however, has elevated temperatures and in some areas high dissolved gas levels associated with the operation of the dams, according to Ecology’s 303(d) List. With so little direct discharge to the river coming from the City of Kennewick, and most of the discharges being made during the colder winter months, the surface water runoff from the City of Kennewick is not considered to be a major contributor to these types of regional water quality problems that are occurring within the river. The City requires onsite erosion control to address the potential water quality problems during construction in advance of major storm events. It is anticipated that erosion and sedimentation during new construction projects will be minor, unless there is a large stormwater event. The City’s Wellhead Protection Plan (WHPP) recorded elevated levels of nitrates in some of the groundwater samples that were collected from local wells. However, these were generally believed to be due to regional large-scale agricultural practices and not to stormwater runoff (Golder, 1997). The WHPP also mentioned the presence of 167 fuel and automobile service sites within the wellhead protection ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-15 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc zone, located primarily within the lower reaches of the Zintel Canyon Basin. The WHPP concluded that hydrocarbons generally do not readily pass through the types of sandy soils present in the Kennewick area. In addition, the WHPP states that the risk to the City’s main aquifer from stormwater infiltration was less than other risks, including spills associated with transportation corridors, leakage from underground tanks, and direct industrial discharges to onsite drywell systems. Stormwater Discharges to Irrigation Canals Stormwater Discharges to Irrigation Canals Stormwater Discharges to Irrigation Canals Stormwater Discharges to Irrigation Canals The interface between the City’s stormwater system and the irrigation canals is the natural result of history and topography. The irrigation ditches were constructed long before much of the City’s existing drainage system was put in place. Irrigation canals tend to follow common topographic elevations. Stormwater runoff, on the other hand, tends to flow downhill, generally perpendicular to the flow of the irrigation canals. Thus, the frequent intersection of these two infrastructures is common throughout the City. The City has mapped and documented locations of stormwater discharges into CID Canals. The documentation includes a location description, longitude, latitude, drainage area, drainage description, and any additional comments. At many of these locations, stormwater only discharges into the canals during larger storm events. At other locations, such as at 14th Avenue and Everett Street, there are stormwater pipes that discharge directly into the canals almost year round. Inventory and mapping of any additional stormwater/canal discharges of CID and KID is in progress. The locations, where stormwater is discharged into the irrigation canals shown in Figure 4-4. Additional information about each of the discharges is presented in Table 4-2. There are also occasions when the irrigation ditches discharge directly into the City’s surface water drainage system. This may occur when a heavy summer rain comes, while the irrigation canals are full, or when the canals are intentionally discharged into the City’s drainage system just prior to the winter freeze. The irrigation system and the City’s drainage system have a unique, symbiotic, inter-working relationship. Most of the storm-to-irrigation-system flow exchanges occur during the winter months, when the irrigation systems are dry. This type of connection provides additional conveyance capacity for stormwater and may also provide detention and attenuation of peak flows. Because this interaction may reduce the potential for large scale flooding throughout the city, the future separation of these two regional drainage infrastructures should be carefully considered. ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-16 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc A joint operational plan between the City and regional irrigation districts could result in a seasonally based program. During the summer, the irrigation districts would optimize the use of the canals and stormwater system for irrigation, during the winter months, when the canals are dry and the city needs detention and conveyance, the City could optimize the system to manage larger storm events and prevent flooding. Potential Cross and Illicit Connections Potential Cross and Illicit Connections Potential Cross and Illicit Connections Potential Cross and Illicit Connections In many cities, cross and/or illicit connections to the storm drain system are common. These usually take the form of older industrial drains that were originally connected to the city’s storm drain system. These systems date back to a time when all waste drainages, including sanitary and industrial, were combined and disposed of with the stormwater. Over time these older drain lines may have even been forgotten and their current presence and status may not be known to their current owners. The cross/illicit connection issue is somewhat different for the City of Kennewick. The City is primarily serviced by hundreds of local drywells. The City lacks a centralized pipe system for the collection and disposal of stormwater runoff. Due to the lack of a centralized system, the potential presence of cross/illicit connections is much less than most urbanized cities. However, if cross/illicit connections do occur, the risk that they present to the City’s shallow groundwater aquifers may be greater than in a typical regional piped storm system. Cross/illicit connections may directly discharge untreated wastewater to local drywells, which could enter the City’s relatively shallow unconfined system of aquifers, from which the City draws its water supply. The City currently has ordinances that prohibit the discharge of waste into the City’s wastewater collection system and municipal water supplies. The City also has adopted a Wellhead Protection Program that requires all commercial and industrial sites within the designated wellhead protection area to be notified. (Refer to Figure 3-7 for the location of the City’s designated wellhead protection area.) These site owners are to be educated regarding the correct design, use and maintenance of these onsite drywells, and the risk that they present to the City’s water supply (Golder, 1997). The City is currently mapping commercial and industrial areas by Standard Industrial Classification (SIC) code as part of its Wellhead Protection Program. Additionally, the City is in the process of inspecting its storm drainage system, including televising all pipelines, and will identify and map all illicit connections. This information will be shared with the City’s Stormwater staff as it is available, to begin the process of eliminating all illicit connections. ---PAGE BREAK--- Section 4 — Existing Stormwater System C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-17 hdr/otak 354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc Table 4-2 Stormwater Discharges into CID Canals Location Name Location Description Longitude Latitude Canal Station Pipe Invert Elevation Drainage Area (Sq Ft) Drainage Description Comments K1 K1 K1 K1 Columbia Center Boulevard / SR 240 119° 13’ 25” 46° 13’ 51” 1,834,700 Columbia Center Boulevard south to Deschutes and Kennewick Park 1 Subdivision. Includes detention pond at Canal Drive and Columbia Center Boulevard. There is a pipe under the canal which flows to the WSDOT drainage system, which handles overflows during weather events. K2 Canal Drive east of Tri City Country Club and west of Lyle 119° 8’ 10” 46° 12’ 44” 155,300 North Newport and North Mayfield Streets. Runs water only during storm events. K3a Garfield / Carmichael / Vineyard 119° 7’ 38” 46° 12’ 28” 208,200 Short sections of Vineyard Drive and South Garfield Street. Carmichael Drive between Kennewick Avenue and Vineyard Drive. One of two discharge pipes into CID canal serving this area. Runs water only during storm events. K3b Garfield / Carmichael / Vineyard 119° 7’ 36” 46° 12’ 27” 208,200 Short sections of Vineyard Drive and South Garfield Street. Carmichael Drive between Kennewick Avenue and Vineyard Drive. One of two discharge pipes into CID canal serving this area. Runs water only during storm events. K4 6th Avenue / Washington Street 119° 7’ 00” 46° 12’ 9” 73,600 6th Avenue between Auburn Street and Washington Street. Washington Street between CID canal crossing and 7th Avenue. Runs water only during storm events. This is where we first see the CID canal holding water during the non-irrigation season. K5 10th Avenue / Alder Street 119° 6’ 56” 46° 11’ 53” 100,600 10th Avenue from halfway between Auburn Street and Washington Street to Alder Street. Washington Street from where 9th Avenue would be to 10th Avenue. Alder Street from 8th Avenue to 10th Avenue. Runs water only during storm events. Water runs to areas where it ponds up during non-irrigation season. K6 14th Avenue / Everett Street near Bethlehem Lutheran School 119° 7’ 29” 46° 11’ 44” 1,673,300 Garfield Hill and Park Hills Subdivisions. Water runs year-round; heaviest during storm events with water coming out of Blackberry Canyon. Groundwater outlet out of the canyon also. K7a 16th Avenue / South Dayton Place 119° 7’ 29” 46° 11’ 40” 222,000 Guthrie’s Addition Subdivision. Runs water only during storm events. This is one of two discharge pipes serving this area. K7b 16th Avenue / South Dayton Place 119° 7’ 25” 46° 11’ 36” 222,000 Guthrie’s Addition Subdivision. Runs water only during storm events. This is one of two discharge pipes serving this area. K8 21st Avenue / South Dayton Place 119° 7’ 16” 46° 11’ 21” 250,000 Kenwood Terrace Subdivision. Historically, this has been discharged through a pumping station into the CID canal. It is presently being eliminated with contract DPW 98-18 which will re-route the stormwaters underneath the CID canal to the City’s detention pond at 23rd Avenue east of Washington Street. Project completed during the completion of this report. K9 East 10th Avenue / West of Hawthorne 119° 6’ 23” 46° 11’ 53” 149,100 10th Avenue between CID canal east to Kingwood Street. Short sections of Hawthorne, Ivy, Juniper, and Kingwood Streets all north of 10th Avenue. Runs water only during storm events. K10 10th Avenue / Chemical Drive 119° 5’ 38” 46° 11’ 54” 145,400 Short sections of 7th and 10th Avenues and short section of Oak Street. Runs water only during storm events. ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-18 hdr/otak 354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc This page left blank intentionally. ---PAGE BREAK--- Section 4 — Existing Stormwater System C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-19 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc Drywell Effectiveness Drywell Effectiveness Drywell Effectiveness Drywell Effectiveness The issue of the effectiveness of drywells for the treatment of stormwater runoff prior to discharge and/or infiltration has been of major concern to the Washington State Department of Ecology. Over the last few years Ecology has sponsored research and discussions on this topic. Some of the general opinions coming out of the discussion are that: • Sand and gravel, by themselves, generally provide little removal or treatment of pollutants commonly found in urban stormwater runoff. Sand, however, generally provides better treatment than coarse gravel. • The more organic material in the sand and gravel, the more effective the soil is at trapping and removing pollutants, • If the soils are adequate, three to five feet of soil above a shallow aquifer is generally adequate for the treatment/pretreatment of infiltrated stormwater prior to its discharge into the shallow aquifer. Ecology and a committee of east-side municipalities, including the City of Kennewick, worked together to draft the State’s new Underground Injection Control (UIC) Rule. The law was completed and adopted February 2006. Additional details concerning the UIC rule are presented in Section 6. Stormwater Infilt Stormwater Infilt Stormwater Infilt Stormwater Infiltration Risk to ration Risk to ration Risk to ration Risk to City’s Groundwater Supplies City’s Groundwater Supplies City’s Groundwater Supplies City’s Groundwater Supplies While the moderately high to high infiltration rates of City soils are great for infiltrating stormwater and for groundwater recharge, they also pose a potential risk for groundwater contamination. The City’s Wellhead Protection Plan defines areas of wellhead protection areas around each of the two Ranney wells. Within the wellhead protection areas land use is predominantly residential, which is considered a low contamination risk. High risk commercial and industrial areas are predominantly located within the 0.5- and 1-year time of travel wellhead protection boundaries. Considering that the City requires businesses to infiltrate all stormwater onsite, any onsite contamination will likely infiltrate. The WHPP provides addresses of 169 potential contamination sources within the wellhead protection area and its buffers, with the biggest contributors being automobile service/fueling businesses followed by dry cleaning businesses (Golder, 1997). The location of infiltration systems in the City of Kennewick is extremely important with regards to continuing to sustain the high quality of the City’s drinking water. The City trains their employees to manage high-risk systems through increased field inspections and annual maintenance. However, the City does not currently provide guidance in locating or designing future stormwater infiltration systems in a way that will protect the groundwater supply. The City will need to develop such guidelines for compliance with the UIC Rule. ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-20 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc Impacts from New Development Impacts from New Development Impacts from New Development Impacts from New Development The City’s existing drainage system is undersized in some areas and localized flooding is common in many parts of the City. Historically, few controls were put on new development and the cumulative impacts of increased peak flows from these increased impervious areas have created the City’s existing drainage problems. Future development will be required to provide water quality treatment, onsite surface water retention, and on-site discharge via infiltration (if soils allow), according to the City’s current drainage design standards. However, even with these restrictive standards the total volume of runoff from new development will increase. While the pre-existing flows will be maintained, the duration of many of these discharges will likely increase. New development simply produces more runoff through the addition of impervious surfaces. This gradual increase in surface water runoff will further tax the capabilities of the City’s existing drainage system, which is reaching or over capacity in many locations. The surrounding unincorporated areas of Benton County, upstream of the City will also continue to send increased amounts of surface water runoff into the City of Kennewick. In the Zintel Canyon Basin, the Zintel Dam will play a large role in attenuating these flows by slowly releasing them into the conveyance system. In other areas of the City’s UGA, increased surface drainage from new development will flow directly into the City, following natural drainage courses. The City’s drainage system needs to be upgraded to accommodate increased runoff from future development. These development-related impacts can be accommodated and should be planned for in advance through the City’s Six-Year Stormwater Capital Facilities Plan. Role of Role of Role of Role of Existing Stormwater System Existing Stormwater System Existing Stormwater System Existing Stormwater System The City of Kennewick’s regional drainage system has been constructed over time as a jointly operated system of facilities between the City, Corps, and two irrigation districts. Each of the four entities know their respective roles and have successfully coordinated over the years to provide regional drainage, flood control, irrigation, water quality treatment, and groundwater recharge/water supply to the surrounding area. This mixture of local and regional facilities is an effective system that meets the drainage needs of the City, while providing for continued future development opportunities. The system also has its own that require first-hand knowledge for proper operation. Major findings from this study of the City’s existing stormwater system include: • The City’s drainage system is composed of several shallow ditches, some piping, several R/D ponds, and numerous drywell facilities, which provide localized ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-21 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc infiltration. Most water infiltrates via drywells located throughout the City, except during some of the larger storm events. • 7 of the City’s 18 drainage basins, including Steptoe, Vista Field, Garfield Canyon, Sunset, Columbia Center Boulevard, Cascade, and Haxton Drain, are closed depressions that infiltrate almost all stormwater runoff, except during the larger storm events. • The City’s existing approach to stormwater management, by the infiltration of almost all stormwater runoff via drywells, works well in most locations. Where infiltration rates are too slow, localized flooding is a concern, and where infiltration rates are too fast, pollution of shallow groundwater is a concern. • Since the construction of the Zintel Dam, and associated Rainier Pipe Conveyance System, the threat of major flooding within the City has been significantly reduced. There is little flooding, except during unique winter events of heavy rains on frozen ground. • Where drainage problems occur, it is usually the result of failing drywells, which have been located in soils that are inadequate for performing sustained rates of infiltration. Some of these failing drywells have been retrofitted by City crews. • The City does not allow detention facilities except in rare circumstances and only with the approval of the City Engineer. Surface retention facilities are designed to retain the 10-year event, 24-hour duration for winter conditions (frozen ground, no allowance for infiltration). Conveyance systems are designed to the 25-year summer event peak flows. • The City should continue to use and enforce its drainage design standards for new developments. These standards should be upgraded to require all new developments to perform a analysis to the point of ultimate disposal or discharge. • The City has completed some, but not all, of the five capital projects identified in the 1990 Flood/Stormwater Plan. Drywell retrofits are an annual program. Conway Pipeline is 70 percent complete. New alternatives are being evaluated for the Garfield Pipeline. • The City should establish a joint development review process, via an inter-local agreement with Benton County, to ensure new drainage facilities constructed within the City’s UGA are built according to the City’s drainage design standards. • Drywell failures have been noted to occur throughout the City. Alternative systems are needed in areas unsuitable for drywell infiltration. An annual capital program is recommended to continue to retrofit and replace failing drywells. This will likely be a growing annual need as the City’s system of over 2,000 drywells continues to age. It would be wise to anticipate this need and establish a formal drywell evaluation/retrofit/replacement program (i.e. a program for planned obsolescence). ---PAGE BREAK--- Section 4 — Existing Stormwater System Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 4-22 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 4.doc • The annual capital program should include funding to build or replace ponds and conveyance systems as the needs arise. As with drywell replacement, this is likely to be a growing annual need as surface water flows increase with increased development. • The inter-relationship between the City’s drainage system and the two regional irrigation systems warrants further study. Stormwater discharges to the irrigation system provide additional conveyance capacity. Separating the two systems will likely increase demand on the City’s existing drainage system. A joint operational plan between the City and the irrigation districts could results in a seasonally based program that would assure continued harmonious operation of the two systems. • There is little water quality treatment, even though there are increasing concerns about the contamination of the City’s shallow groundwaters that provide the City’s primary drinking water supply. • While there is little evidence of water quality problems in runoff, surface waters, or groundwaters, there is also a void of information about the water quality throughout the region. It would be a good investment to start a public education and outreach program to educate both citizens and local businesses. A higher focus should be placed on educating high risk businesses (gas stations, dry cleaners, manufacturers, material handlers, paint shops, transporters etc.) about what they can do to keep their stormwater runoff clean and pollutant free. • A regional spill response program, as part of the City’s Wellhead Protection Program, should be established that is well communicated and well coordinated to avoid contamination of the City’s rather shallow aquifers. Annual training should occur, simulating major spills associated with the railroads, highway system, and local businesses. • Continued growth is eliminating natural drainage features, increasing runoff rates and volumes, and increasing concern about water quality and contamination of shallow groundwater resources. With increased development, added pressure is being placed on the City’s drainage system. Peak flow rates and volumes of surface water runoff are expected to increase. Pollutant loading is expected to increase as well. ---PAGE BREAK--- East Amon Basin Zintel Canyon Cascade Conway Canyon Elliot Lake Zintel Dam Basin Williams Basin Canal Garfield Canyon Sunset Columbia Park Duffy's Pond East Kennewick Haxton Drain Vista Field Steptoe Columbia Center Blvd Edison St. 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST E A ST W 4TH AVE S OAK ST S CLODFELTER RD W KENNEWICK AVE GAGE BLVD E CHEMICAL DR E BOWLES RD S OLYMPIA ST E BADGER RD E 10TH AVE E 27TH AVE E LEWIS ST W 45TH AVE N 14TH AVE N KELLOGG ST N 4TH AVE N 20TH AVE N EDISON ST STATE HWY 397 S UNION ST N RD 36 N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE N GUM ST S MORAIN ST W AINSWORTH ST S KELLOGG ST N YELM ST E FINLEY RD N RD 56 E AINSWORTH ST E 1ST AVE FAIRWAY ST S RD 28 COLUMBIA PARK TRAIL S 1ST ST W 1ST AVE N OREGON AVE E AINSWORTH AVE N COLUMBIA CENTER BLVD KEENE RD S COLUMBIA CENTER BLVD S 20TH AVE RD 56 VINEYARD DR S OLYMPIA ST EXISTING DRAINAGE CONDITIONS   395 City of Richland Columbia River FIGURE 4-1 Family Fishing Pond Duck Pond Frog Pond Duffy's Pond WWTP Lagoons Zintel Dam Elliot Lake Mall R/D Facility City of Pasco E. 23rd R/D Facility Clearwater R/D Facility   395 Legend Outfalls Army_Corps_Pumps City Bndy UGA Bndy Irrigation Canals Water Bodies Levee RR Tracks R/D Facilities MAJOR FLOW PATHS Flow         Over Land
0 1,400 2,800 4,200 5,600 700 Feet Golf Course Ponds W. Canal Dr Columbia Center R/D Facility Area flows directed toward Steptoe and City of Richland conveyance system. ---PAGE BREAK---






































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST E A ST W 4TH AVE S OAK ST S CLODFELTER RD W KENNEWICK AVE GAGE BLVD E CHEMICAL DR E BOWLES RD S OLYMPIA ST E BADGER RD E 10TH AVE E 27TH AVE E LEWIS ST W 45TH AVE N 14TH AVE N KELLOGG ST N 4TH AVE N 20TH AVE N EDISON ST STATE HWY 397 S UNION ST N RD 36 N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE N GUM ST S MORAIN ST W AINSWORTH ST S KELLOGG ST N YELM ST E FINLEY RD N RD 56 E AINSWORTH ST E 1ST AVE FAIRWAY ST S RD 28 COLUMBIA PARK TRAIL S 1ST ST W 1ST AVE N NEEL ST S WASHINGTON ST N OREGON AVE E AINSWORTH AVE N COLUMBIA CENTER BLVD N MORAIN ST KEENE RD S COLUMBIA CENTER BLVD W QUINAULT AVE S 20TH AVE RD 56 VINEYARD DR S OLYMPIA ST MAN-MADE DRAINAGE FEATURES   240   395 City of Richland Columbia River FIGURE 4-2 Family Fishing Pond Duck Pond Frog Pond Duffy's Pond WWTP Lagoons Zintel Dam Elliot Lake Mall R/D Facility City of Pasco E. 23rd R/D Facility Clearwater R/D Facility   395 Legend Storm Drainage Lines Storm Manholes
Storm Catch Basins City Bndy UGA Bndy Outfalls Army Corps Pumps Irrigation Canals Water Bodies RR Tracks
0 1,400 2,800 4,200 5,600 700 Feet Golf Course Ponds W. Canal Dr Columbia Center R/D Facility ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST E A ST W 4TH AVE S OAK ST S CLODFELTER RD W KENNEWICK AVE GAGE BLVD E CHEMICAL DR E BOWLES RD S OLYMPIA ST E BADGER RD E 10TH AVE E 27TH AVE E LEWIS ST W 45TH AVE N 14TH AVE N KELLOGG ST N 4TH AVE N 20TH AVE N EDISON ST STATE HWY 397 S UNION ST N RD 36 N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE N GUM ST S MORAIN ST W AINSWORTH ST S KELLOGG ST N YELM ST E FINLEY RD N RD 56 E AINSWORTH ST E 1ST AVE FAIRWAY ST S RD 28 COLUMBIA PARK TRAIL S 1ST ST W 1ST AVE N NEEL ST S WASHINGTON ST N OREGON AVE E AINSWORTH AVE N COLUMBIA CENTER BLVD N MORAIN ST KEENE RD S COLUMBIA CENTER BLVD W QUINAULT AVE S 20TH AVE RD 56 VINEYARD DR S OLYMPIA ST STORM DRYWELLS   240   395 City of Richland Columbia River FIGURE 4-3 Family Fishing Pond Frog Pond Duffy's Pond WWTP Lagoons Zintel Dam Elliot Lake Mall R/D Facility City of Pasco E. 23rd R/D Facility Clearwater R/D Facility   395 Legend City Bndy UGA Bndy Storm_Drywells2 Irrigation Canals Water Bodies RR Tracks
0 1,400 2,800 4,200 5,600 700 Feet Golf Course Ponds W. Canal Dr Columbia Center R/D Facility ---PAGE BREAK---


























82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST E A ST W 4TH AVE S OAK ST S CLODFELTER RD W KENNEWICK AVE GAGE BLVD E CHEMICAL DR E BOWLES RD S OLYMPIA ST E 10TH AVE E 27TH AVE E LEWIS ST W 45TH AVE N 14TH AVE N KELLOGG ST N 4TH AVE N 20TH AVE N EDISON ST STATE HWY 397 S UNION ST N RD 36 N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE N GUM ST S MORAIN ST W AINSWORTH ST S KELLOGG ST N YELM ST E FINLEY RD N RD 56 E AINSWORTH ST E 1ST AVE FAIRWAY ST S RD 28 COLUMBIA PARK TRAIL S 1ST ST W 1ST AVE N NEEL ST S WASHINGTON ST N OREGON AVE E AINSWORTH AVE N COLUMBIA CENTER BLVD N MORAIN ST KEENE RD S COLUMBIA CENTER BLVD W QUINAULT AVE S 20TH AVE RD 56 VINEYARD DR S OLYMPIA ST EXISTING SYSTEM CONCERNS   395 City of Richland Columbia River FIGURE 4-4 City of Pasco   395 Legend Irrigation Canals Water Bodies City Bndy UGA Bndy RR Tracks System Concerns
Documented Capacity
Discharge to Non-City Property
Discharge to Irrigation
0 1,400 2,800 4,200 5,600 700 Feet W. Canal Dr K1 K2 K3a K3b K4 K5 K6 K7a K7b K8 K9 K10 K8 City tracking number ---PAGE BREAK--- 82   240 US HWY 395 US HWY 12 COLUMBIA PARK TRAIL W 10TH AVE W COURT ST W CANAL DR LESLIE RD E A ST W A ST W CLEARWATER AVE W 27TH AVE S ELY ST S HANEY RD W LEWIS ST W SYLVESTER ST W 4TH AVE S CLODFELTER RD S OAK ST E LEWIS ST E BOWLES RD STATE HWY 397 W KENNEWICK AVE GAGE BLVD E CHEMICAL DR S OLYMPIA ST N 14TH AVE N RD 36 E 10TH AVE N 4TH AVE N 20TH AVE E FINLEY RD E 27TH AVE W 45TH AVE N KELLOGG ST E AINSWORTH AVE N EDISON ST S UNION ST N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE N OREGON AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL S RD 28 W 1ST AVE S 1ST ST N NEEL ST N RD 68 S WASHINGTON ST KEENE RD E BADGER RD N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST S COLUMBIA CENTER BLVD KENNEWICK AVE AVENUE G W QUINAULT AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S KEYSTONE ST S OLYMPIA ST PREVIOUS STUDY CAPITAL PROJECTS Legend Lakes and Rivers Irrigation Canals City Bndy UGA Bndy RR Tracks Constructed Conway Pipeline Kennewick Park Subdivision South Ranier Pipeline
0 1,400 2,800 4,200 5,600 700 Feet   395 Columbia River FIGURE 4-5 1 - South Ranier Pipeline - Installation of 4600 LF of 72 inch storm drain pipeline. 2 - Kennewick Park Subdivision - Install storm drain pipe between existing drywells and provide a overflow channel to exit the subdivision. 3 - Citywide Drywell Replacement and Interconnection - Replacement of failed drywells throughout various locations in Kennewick and interconnection of failed drywells to adequately performing drywells in other areas. 4 - Conway Pipeline - Replace existing undersized storm drain, construct detention basin, and upgrade channel. Not Constructed Garfield Pipeline 27th and Gum Retention Facility 5 - Garfield Pipeline - Install 3200 LF of storm drainline ranging in size from 39 to 48 inches. 6 - 27th & Gum Retention Facility - Install 33 acre-foot regional retention facility. 2 4 1 5 6 3 ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-1 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc Introduction Introduction Introduction Introduction Continued growth in and around the City Kennewick over the last 10-15 years has created challenges for the City’s Stormwater Program. The City is also faced with a number of upcoming regulatory requirements associated with the NPDES Phase II Municipal Stormwater Permit and the State’s new Underground Injection Control Rule (UIC). In response to the region’s continued growth and these pending regulatory requirements, the City is conducting an assessment of its stormwater needs by reviewing its existing stormwater services, organization, staffing, and regulatory obligations. The objective of this review is to document existing activities, services, and levels of funding in light of the various pending regulatory requirements. This will allow the City to take credit for existing activities, as it identifies what additional activities may be needed to achieve compliance with NPDES and UIC stormwater regulatory requirements. It is likely that these new regulatory guidelines will require the City to increase its local stormwater services and annual level of funding. Following this analysis of the City’s existing Stormwater Program, a regulatory “gap analysis” is presented in Section 6 that compares the City’s existing SWM Program with the various regulatory requirements. Capital improvement projects are presented in Section 7, along with resources and costs, corresponding to the capital recommendations. Potential funding mechanisms are presented in Section 8 in association with a five year implementation plan. Existing Stormwater Program Existing Stormwater Program Existing Stormwater Program Existing Stormwater Program Responsibilities, Activities, and Annual Budget Responsibilities, Activities, and Annual Budget Responsibilities, Activities, and Annual Budget Responsibilities, Activities, and Annual Budget The City of Kennewick Municipal Services Department manages much of the City’s stormwater program and drainage facilities. The direction of the existing program is determined by the Director of the Public Works, who delegates much of the responsibility to the City Engineer and Maintenance & Operations (M/O) Manager. The City Engineer and M/O Manager are responsible for the City’s Stormwater Program, staff, annual work program and related activities. Much of the day-to-day direction of the Program, however, is further delegated to a Senior Project Engineer, who often gets guidance directly from the Public Works Director. The City’s Municipal Services Department Stormwater Program is funded on an annual basis from a compilation of various sources, including revenues from the City’s Street Department and the Water/Sewer Department. Annual SWM activities and capital projects are primarily funded from of the City’s 0.5% sales tax that is currently dedicated to street and other capital improvements. ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-2 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc Revenues, allocated to the City’s Stormwater Program, amount to about $400,000 per year on the average. In the 2004 and 2005 budgets, about $73,000 of this amount was allotted for labor, benefits, and expenses from the Street Fund. This includes general storm drainage maintenance ($20,000) and source control through street sweeping ($53,000). An additional $131,000 is budgeted from the Water/Sewer Funding for Dry Well/Catch Basin Cleaning ($106,000), Storm Drainage Repairs & Flood Control ($15,000), and Inventory & Detection ($10,000). The remaining $200,000 goes toward the design and construction of capital projects, as annual funding allows. In addition, Municipal Services Engineering and Inspection staff conduct stormwater plan review and inspection for public and private developments, which is funded primarily by development fees. The maintenance services for the City’s Stormwater Program are performed by the M/O Division of the Public Works Department and the Parks, Streets, and Facilities Division (Facilities). Both divisions are located within the Municipal Services Department. Management and direction of annual stormwater maintenance activities is a shared responsibility of the M/O Utilities Supervisor and the Facility and Grounds Supervisor. Much of the day-to-day management responsibility is delegated to the lead crew foremen within each of these two respective divisions. Day-to-day drainage maintenance services are provided by a 2 – 3 person maintenance crews, who operate the vactor trucks, conduct street sweeping, and respond to complaints and other drainage emergencies. The City has a small pay-as-you-go annual capital improvement fund of about $200,000 per year for the construction of new facilities, or the repair and/or replacement of older or damaged facilities. The amount of funding available for capital projects varies from year to year. For this reason, many of the City’s current stormwater facilities have been designed and constructed in conjunction with road and/or other utility infrastructure projects. New developments are also often requested to upgrade and/or replace existing undersized drainage facilities for the City as a condition of their permit approval. Organization Organization Organization Organization The City’s existing Stormwater Program is composed primarily of staff, equipment, and resources from three divisions within the Municipal Services Department: the City Engineer’s Office, the M/O Division (of Public Works), and the Facilities Division (Figure 5-1). The City’s Community Planning Department and the Finance Division of the Support Services Department also support the Stormwater Program. Planning implements the City’s Growth Management Plan, and in so doing manages the development approval process, performs zoning reviews, participates in regulatory compliance activities, and provides some regional coordination. The ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-3 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc Finance Office provides assistance to the City’s Stormwater Program by annually allocating, reporting, and tracking stormwater funds and expenditures. Figure 5-1 shows the general organization of the City of Kennewick’s Municipal Services Department, which includes each of the divisions mentioned above. Services Services Services Services The Municipal Services Department has the primary responsibility for the City’s Stormwater Program, including leading the response to the various regulatory requirements. Within the Public Works Division drainage-related activities are divided into two main areas of service: engineering and maintenance. The engineering services are composed of stormwater program direction and implementation, regulatory compliance, watershed and regional coordination, with some participation in development review and permitting processes. The maintenance services, performed by both the Public Works Division and the Facilities Division, ensure that existing drainage facilities are inspected and adequately maintained on an annual basis. Primary maintenance activities include street sweeping and drywell & catch basin maintenance. The major activities of the City’s Stormwater Program are summarized in Figure 5-2, according to the various elements of service delivery. Staffing Staffing Staffing Staffing About 3.5 full time equivalent (FTE) staff support the City’s Municipal Services Department Stormwater Program on an annual basis, as shown in the Staffing Analysis summarized in Table 5-1. Most of the drainage staff are located within the Municipal Services Department, with 1.5 FTE in Engineering and 2.0 FTE in Maintenance. Some staffing is also provided by the Community Development Department (Planning) and the Finance Office throughout the year, on an as-needed basis. Adopting ordinances, enacting enhanced development review procedures, adopting drainage standards for new development and re-development, and some educational activities are stormwater related activities that require Community Planning Department involvement. ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-4 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc Figure 5 Figure 5 Figure 5 Figure 5-1 ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-5 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-6 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc Table 5 Table 5 Table 5 Table 5-1 City of Kennewick Existing SWM Program: Staffing Analysis City of Kennewick Existing SWM Program: Staffing Analysis City of Kennewick Existing SWM Program: Staffing Analysis City of Kennewick Existing SWM Program: Staffing Analysis Responsible Department Responsible Department Responsible Department Responsible Department Responsible Staff Responsible Staff Responsible Staff Responsible Staff Municipal S Municipal S Municipal S Municipal Services ervices ervices ervices Comm Dev Comm Dev Comm Dev Comm Dev Finance Finance Finance Finance Program Element Program Element Program Element Program Element Engineering Engineering Engineering Engineering Maintenance Maintenance Maintenance Maintenance Director Director Director Director City City City City Eng. Eng. Eng. Eng. O/M O/M O/M O/M Super* Super* Super* Super* Eng Eng Eng Eng Staff Staff Staff Staff OM OM OM OM Staff* Staff* Staff* Staff* Inspector Inspector Inspector Inspector Planner Planner Planner Planner Code Code Code Code Enfor Enfor Enfor Enfor Finance Finance Finance Finance Assist Assist Assist Assist 1. 1. 1. 1. Admin Admin Admin Admin 0.15 0.15 0.15 0.15 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 2. 2. 2. 2. CIP CIP CIP CIP 0.10 0.10 0.10 0.10 0.05 0.05 0.05 0.05 0. 0. 0. 0.05 05 05 05 3. 3. 3. 3. O/M O/M O/M O/M 0.10 0.10 0.10 0.10 1.80 1.80 1.80 1.80 0.05 0.05 0.05 0.05 0.10 0.10 0.10 0.10 0.05 0.05 0.05 0.05 1.70 1.70 1.70 1.70 4. 4. 4. 4. Dev. Review Dev. Review Dev. Review Dev. Review 0.35 0.35 0.35 0.35 0.05 0.05 0.05 0.05 0.30 0.30 0.30 0.30 5. 5. 5. 5. Pub. Ed. Pub. Ed. Pub. Ed. Pub. Ed. 6. 6. 6. 6. Insp Insp Insp Inspect/Enforce ect/Enforce ect/Enforce ect/Enforce 0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.25 7. Compliant 7. Compliant 7. Compliant 7. Compliant/Emer Emer Emer Emergency gency gency gency Response esponse esponse esponse 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 8. 8. 8. 8. Watershed Watershed Watershed Watershed/GMA Planning MA Planning MA Planning MA Planning 9. 9. 9. 9. Critical Area Critical Area Critical Area Critical Areas, Wetland s, Wetland s, Wetland s, Wetland 10. 10. 10. 10. Tech. Support Tech. Support Tech. Support Tech. Support 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 11. 11. 11. 11. Regional C Regional C Regional C Regional Coord. oord. oord. oord. 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 12. 12. 12. 12. NPDES II NPDES II NPDES II NPDES II 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 13. 13. 13. 13. UIC Rule UIC Rule UIC Rule UIC Rule 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 14. 14. 14. 14. ESA ESA ESA ESA 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05 15. 15. 15. 15. Debt & Taxes Debt & Taxes Debt & Taxes Debt & Taxes 16. 16. 16. 16. Eq Eq Eq Equipment uipment uipment uipment 17. 17. 17. 17. Repair / Replace Repair / Replace Repair / Replace Repair / Replace 18. 18. 18. 18. WQ WQ WQ WQ / Monitoring Monitoring Monitoring Monitoring 19. 19. 19. 19. Legal / Legal / Legal / Legal / Ordinances Ordinances Ordinances Ordinances 20. Legal Advice/ 20. Legal Advice/ 20. Legal Advice/ 20. Legal Advice/Support Support Support Support 21. 21. 21. 21. Outside Services Outside Services Outside Services Outside Services 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 Total FTE Count 1.55 1.55 1.55 1.55 1.95 1.95 1.95 1.95 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.05 0.05 0.05 0.05 0.20 0.20 0.20 0.20 0.15 0.15 0.15 0.15 1.30 1.30 1.30 1.30 1.80 1.80 1.80 1.80 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Total Total Total Total 3.5 3.5 3.5 3.5 3.5 FTE 3.5 FTE 3.5 FTE 3.5 FTE *Maintenance responsibilities are shared between Public Works maintenance and operations, and parks, streets, and facilities maintenance and operations. ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-7 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc Equipment and Materials Equipment and Materials Equipment and Materials Equipment and Materials At this time, the City’s Stormwater Program exists as a series of services that are provided by staff from several divisions within the Municipal Services Department. There is no separate Stormwater Division. As such, equipment, vehicles, and materials must be rented from the City’s Public Works M/O Division and the Facilities Division on an as-needed basis. Annual stormwater maintenance and source control activities, equipment and materials include the following. • Catch basins and dry wells are routinely cleaned by the two vactor trucks located within the City’s Water and Sewer Program. Two vactor trucks are in full time use. • Regular street sweeping is performed by the City’s Street Dept. Arterial roads are swept every three weeks and residential streets are swept quarterly. There are currently three vacuum sweepers in operation. • Culverts are replaced and tools and materials for maintenance, repair, and replacement are purchased as needed through one of the two maintenance divisions’ annual budgets. The City operates a street waste facility which handles street sweeping wastes and dry well cleaning wastes. Materials collected at this facility are tested for Resource Conservation and Recovery Act (RCRA) metals and Total Petroleum Hydrocarbons (TPH). If these wastes are within Washington State Model Toxics Control Act (MTCA) limits, they are disposed of at the inert landfill. There have been no instances in which the MTCA limits have been exceeded since testing of street wastes began in 1993. Ordinances and Legal Authorities Ordinances and Legal Authorities Ordinances and Legal Authorities Ordinances and Legal Authorities The City of Kennewick routinely enforces an array of ordinances, guidelines and practices related to stormwater management. Stormwater management is addressed by the following ordinances, as described in the Kennewick Municipal Code (KMC). Many of these ordinances are related to the City’s sanitary sewer system and the City’s development review and approval processes. Chapter KMC: 4.04 – Administrative Appeals 4.08 – State Environmental Policy Act 4.12 – Permit Process 5.56 – Public Works Construction Standards Section 7-1 - Specs for Storm Drain (Pipe) Section 7-2 - Trench Excavation and Backfill Section 7-3 - Imported Pipe Bedding Section 7-4 - Catch Basin Section 7-5 - Standard Manhole Section 7-6 - Standard Drywell ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-8 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc Section 7-7 - Drywell Percolation Tests Section 7-8 - Abandoned Conduits Section 7-9 - Catch Basin Protection Section 7-10 - Storm Drain Design 9.48 – Nuisance Law 14.22 – Sewerage Services 14.24 – Sanitary Sewerage Connection Charges 14.26 – Sanitary Sewer User Charges 14.28 – Storm Sewer Charges 14.30 – Sewer Backup Prevention 15.41 – Cross-Connections (to the City’s Water System) 18.06 – Districts and Maps 18.89 – Administration and Enforcement 18.92 – Shoreline Management 18.93 – Flood Damage Prevention The City has the ability to review and revise these legal ordinances and standards, as well as create new ordinances, as necessary. Of particular note, KMC 14.28 Storm Sewer Charges has been in effect since 1976. A copy of each of the City’s above mentioned stormwater related ordinances have been included in Appendix A. Funding: Sources and Funding: Sources and Funding: Sources and Funding: Sources and Allocations Allocations Allocations Allocations The City’s stormwater related services are supported in the City’s annual budget from a combination of resources from the Street Department and the Water/Sewer Fund. The City also charges plan review and inspection fees to partially cover the cost of regulating new development. The Street Department spends approximately $73,000 in maintenance and street sweeping services. The Water/Sewer Fund supports dry well/catch basin cleaning, storm drainage repairs & flood control, and inventory & detection with it annual appropriation of $131,000. The remainder of the City’s stormwater program is supported by revenues generated from the City’s dedicated 0.5% sales tax for street related capital improvements. The City’s dedicated 0.5% sales tax was created in 1986 for street capital improvements. As the City has grown over time, this fund has gradually grown to $3.8M per year to meet the financial needs of the City’s growing infrastructure. Average annual revenues from the 0.5% sales tax to the Stormwater Program currently total about $200,000 per year. As shown in Table 5-1, the Municipal Services Department Stormwater Program annually supports 3.50 FTE staff and provides the revenue for $204,000 in labor/benefit costs and other program related expenses (City of Kennewick, 2004/2005 budgets). The expenses include the purchase of annual maintenance supplies, along with some equipment rental (no major equipment purchases). The ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-9 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc division of resources between labor and expenses varies from year to year. Stormwater plan review and site inspection and approval occur within the Municipal Services Department (as a component of overall development review and inspection services). The use of outside consultant services varies from year to year. On occasion and to a much lesser extent, other funding sources including service fees and State loan or grants, are also used to support the City’s Stormwater Program. Neighboring SWM Programs, Plans, and Funding Neighboring SWM Programs, Plans, and Funding Neighboring SWM Programs, Plans, and Funding Neighboring SWM Programs, Plans, and Funding Similar to the City of Kennewick, other local jurisdictions are attempting to address their drainage needs and the emerging regulatory requirements. Listed below are highlights of each of their various stormwater management programs. City of Pasco • Has a Stormwater Program supported by a Stormwater Utility Service Fee. • Their stormwater service fee is based on a water quality estimate that is related to a transportation impacts and a pollutant loading assessment. City of Richland • Developed a comprehensive SWM plan and utility a number of years ago. • Currently updating their plan and will likely need to substantially raise their rates from the existing level, based on a recently completed Stormwater Management Plan. City of West Richland • Has completed a Stormwater Management Plan. • Current stormwater utility rates are about $6 per month for residential customers. Benton County • Has established a set of Stormwater Design Criteria, which they have been using for years for the design of new development. • Currently reviewing their regulatory compliance needs in light of the proposed NPDES II Permit, UIC Rule, ESA, Model Stormwater Program for Eastern Washington and the Stormwater Design Criteria proposed for Eastern Washington. Yakima Area Includes Yakima County, City of Yakima, and City of Union Gap • These three Eastern Washington municipal agencies have decided to work together in defining their stormwater regulatory requirements and meeting their regulatory compliance obligations. ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-10 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc • They have completed a regulatory “gap analysis” for each agency and began the formal process of creating stormwater utilities within each of the agencies in 2004. • The agencies are currently reviewing regionalization options and are considering conducting a value engineering study of the defined programs, after adoption and implementation of stormwater utilities are anticipated. The City of Yakima, which adopted their utility in 2004, is scheduled to begin collecting fees in 2007. Interagency Cooperation Interagency Cooperation Interagency Cooperation Interagency Cooperation To date, the City of Kennewick has had only limited participation in regional stormwater activities with the County or its three adjacent neighboring municipalities of Richland, West Richland, and Pasco. This is largely due to the fact that stormwater planning and establishing stormwater programs are relatively new in Eastern Washington. However, over the last few years each of the four agencies, including the City of Kennewick, have established Stormwater Programs and have been actively participating in the development stormwater regulations for Eastern Washington. The City is also involved in the Watershed Resource Inventory Area (WRIA) #31 Watershed Planning effort. Discussions with City staff show a definite interest in exploring regional cooperation in developing Stormwater Programs that will meet the emerging stormwater requirements for Eastern Washington. Preliminary Evaluation of the City’s Existing Stormwater Program Preliminary Evaluation of the City’s Existing Stormwater Program Preliminary Evaluation of the City’s Existing Stormwater Program Preliminary Evaluation of the City’s Existing Stormwater Program As part of the review and documentation of the City’s existing Stormwater Program, an initial evaluation was made of the extent and adequacy of the Program, its activities, and its staffing and resources. This preliminary evaluation is based on data and documents received from the City, interviews with City staff, site visits, the results of an internal regulatory compliance questionnaire, and a review of the City’s March 10, 2003 NPDES II Permit Application. Data and Documents Data and Documents Data and Documents Data and Documents Based on the data request (Appendix B) made at the initial meeting with City Staff on September 5, 2003, a substantial amount of information in the form of comprehensive water, sewer, land use, flood/stormwater, and wellhead protection plans have been provided by the City. These documents are supplemented by data downloaded from the City’s website that includes the City’s drainage-related ordinances and legal authorities, as presented in Appendix A. St St St Staff Interviews and Site Visit aff Interviews and Site Visit aff Interviews and Site Visit aff Interviews and Site Visit A number of interviews with City staff have occurred since this project started. Highlights from the December 18, 2003 meeting (Appendix C) suggest that: • The worst flooding problems throughout the City have already been addressed. ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-11 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc • The City has a number of nuisance localized drainage problems that create local flooding and are regular maintenance problems for City crews. They are prioritized on a 1-5 scale for response by City crews. • Many of the drywells throughout the city are slow draining and need to be fixed or moved to new locations; in some cases regional retention/detention ponds with water quality pre-treatment may be needed. • Most of the stormwater (99%) has been separated from the City’s sewer system. • There are 10-15 routine maintenance problems that will require small capital solutions. • The overall performance of the City’s system of drywells is not well understood. The performance of individual drywells is unknown until a drywell fails and creates local flooding. • Street sweeping, catch basin sediment removal, drywell maintenance, and complaint response are the predominant activities of the City’s current stormwater maintenance program. • City crews have inventoried and mapped the City’s system of drywells, catch basins, pipes, and ditches, and have created a computerized GIS database. • About $100K to $200K is spent per year on flooding improvements. • Water quality may be an issue, but has not been documented. • Although the City has made the decision to keep stormwater out of the irrigation system, the two systems are interconnected at many locations causing regular operating problems for both the irrigation district and the City. • The City is short on funds to separate the stormwater from the irrigation system or to adequately repair its aging system of drywells. • Public over-watering and silting in of local drywells is a problem. • River flooding is controlled by the Corps. • Duffy’s Pond receives storm run-off without prior water quality treatment. • The City’s preference is to dispose of all stormwater via local drywells. • New commercial and industrial developments are not allowed to connect to the City’s stormdrain system; they must infiltrate up to the 10-year event on site. • The groundwater level is shallow, less than 25 feet in most parts of the City, and even less in the older downtown areas. • Closed depressions and poor infiltrating soils need to be mapped. • The City thinks its Stormwater Program is generally in compliance with the various regulatory requirements. Existing Progra Existing Progra Existing Progra Existing Program Summary m Summary m Summary m Summary Understanding the City’s existing stormwater program is critical in developing recommendations for future programming needs. The elements of the City’s existing stormwater program were compared to elements of a typical stormwater program. Details of this analysis are presented in Appendix D.1. In general, the City has a good basis for developing a comprehensive stormwater program. Previous capital ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-12 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc projects have largely eliminated flooding problems within the City and the existing maintenance activities are normally adequate to keep the stormwater system functioning on an annual basis. A few staff are routinely involved in the City’s various stormwater related activities. Most of their time is spent in O/M and development review activities, with limited participation in regulatory compliance. This review of the City’s existing system is the first step in conducting a regulatory compliance gap analysis. The next step is a preliminary assessment of the City’s existing stormwater program in regard to the six minimum requirements of the NPDES II Permit and the requirements of the UIC Rule, as presented in Section 6. The results of that analysis, presented in Appendix D.2, suggest additional activities the City must undertake to achieve compliance. There are a number of activities listed in the section entitled Initial Assessment that suggest that, while the City has an operationally functional Stormwater Program, the Program falls short of achieving some of the fundamental requirements of the proposed NPDES II General Permit for Eastern Washington. Additional activities, staff, capital projects, and funding will be needed to address these gaps in the existing program, as described in the following sections of this report. Summary of Summary of Summary of Summary of Existing Program Existing Program Existing Program Existing Program and and and and Needs Needs Needs Needs This review of the existing structure, organization, staffing, funding, and equipment of the City’s present Stormwater Program has shown that: • The City of Kennewick has a well-established and well-working Stormwater Program that has evolved over time, as development and local drainage conditions have dictated. The Program wisely takes advantage of natural soils and groundwater conditions to dispose of stormwater in a way that requires relatively little capital investment or annual maintenance. • The active participation of the Corps of Engineers has had a profound effect on the design and operation of the City’s drainage system. Without the Corps involvement, the City’s Stormwater Program would have, by necessity, evolved into an entirely different program, emphasizing flood control, rather than stormwater conveyance and disposal. Such a program would have extensive annual capital and maintenance needs and financial requirements. • The Program is funded for its current types and levels of services, which include catch basin cleaning, drywell cleaning, plan review, construction site inspection, and minor capital repair and replacement projects. It has a dedicated, annual funding source from the City’s Street Fund and development related fees. • Although somewhat complex in its organizational structure and lines of communication, the Program seems to perform well on an annual basis. Each of ---PAGE BREAK--- Section 5 — Analysis of Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 5-13 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 5.doc the participating divisions and staffs know their respective roles and responsibilities. • Some equipment and vehicles are rented and/or replaced as needed through jointly developed, annual operating agreements with the City’s other major infrastructure divisions (i.e. water, wastewater, parks, and streets). Sweepers have been funded solely through the Streets Dept. • Drainage design standards, and other local ordinances, have been outlined for new development that are based on local soils and hydrological conditions, as defined in the City’s 1990 Flood/Stormwater Plan. • There appears to be opportunities to work with neighboring jurisdictions to jointly develop and implement common stormwater program activities, such as public education and other activities associated with future regulatory compliance. • The City has stormwater needs that have not been met in terms of policies, ordinances, equipment, staffing, and retrofit projects for its system of drywells. Meeting these requirements may prove to be a challenge, requiring new activities and additional funding and staffing. • The annual allocation from the City’s Street Fund can be increased; however, annual financial needs may exceed the capabilities of this fund. A new funding source may be needed that would be dedicated to improving stormwater management, water quality enhancement, and groundwater protection throughout the City. • It is likely that the City will need to expand their existing Stormwater Program to meet future regulatory requirements. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-1 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc An Introduction to Regulatory Compliance An Introduction to Regulatory Compliance An Introduction to Regulatory Compliance An Introduction to Regulatory Compliance The City is subjected to a myriad of federal, state, regional and local surface water, groundwater, water quality, and habitat-related requirements. The purpose of this regulatory compliance analysis is to list the various stormwater regulatory requirements and present a strategy for the City of Kennewick to comply. This strategy includes identifying activities and resources required to meet the requirements discussed below. At the federal level, this stormwater regulatory analysis will focus on achieving compliance with: • The National Pollution Discharge Elimination System (NPDES) Phase II Municipal Stormwater Permit, as required by the Clean Water Act (CWA), • The Underground Injection Control (UIC) Rule, as required by the Safe Drinking Water Act (SDWA), and • The stormwater requirements of the Endangered Species Act, Section 4(d). Both NPDES and UIC are administered by the Washington State Department of Ecology in behalf of the federal government. This means that the State of Washington has been delegated the primary authority for administration of the CWA and SDWA. This gives the State the same rights as EPA to interpret, prescribe, and enforce the federal stormwater regulatory requirements, including the NPDES II Permit and UIC Rule. Being a delegated agency, the State may add its own more restrictive requirements, in addition to those required by the Environmental Protection Agency (EPA). When issuing NPDES permits, the State must ensure that federal laws are met, in addition to those laws imposed by the State. To help communities in eastern Washington plan for Phase II of NPDES, Ecology formed and worked with a committee of stakeholders, the Eastern Washington Stormwater Steering Committee, to develop two documents: • The Model Municipal Stormwater Program for Eastern Washington (Model Program), as published by the Department of Ecology in September 2003, and • The Stormwater Management Manual (SWMM) for Eastern Washington, as published by the Department of Ecology in September 2004. Other stormwater requirements that will be discussed include those of the: • Federal/State Wellhead Protection Program, • Federal/State On-Site NPDES Construction Stormwater Permit, • Stormwater Management Manual for Eastern Washington, • Total Maximum Daily Loads and the ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-2 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc • WRIA Watershed Planning Process. Regulatory Requirements Regulatory Requirements Regulatory Requirements Regulatory Requirements State/ State/ State/ State/Federal Federal Federal Federal: NPDES Phase II Municipal Stormwater Permit : NPDES Phase II Municipal Stormwater Permit : NPDES Phase II Municipal Stormwater Permit : NPDES Phase II Municipal Stormwater Permit One of the primary stormwater obligations of the City of Kennewick is achieving compliance with the Clean Water Act. While there are many aspects to this law, one of the most significant for municipal agencies is the requirement for cities like Kennewick to be issued and come under the jurisdiction of the new National Pollution Discharge Elimination System (NPDES) Phase II Permit. The intent of this new NPDES Phase II Municipal Stormwater Permit is to reduce and prevent pollution by controlling the discharges of municipal storm drains into local receiving waters, to the maximum extent practicable. (Note that while there is no clear definition of maximum extent practicable in the federal register, the intent of the law is for each municipality to identify and remove pollutants in local stormwater so that state and federal receiving water quality standards are met and beneficial uses are protected.) The six minimum requirements of the NPDES Phase II Municipal Stormwater Permit, as described by the Environmental Protection Agency in the federal register (December, 1999), include the following: NPDES #1 — Public Education and Outreach NPDES #2 — Public Involvement and Participation NPDES #3 — Illicit Discharge Detection and Elimination NPDES #4 — Construction Site Stormwater Runoff Control NPDES #5 — Post-Construction Stormwater Management for New Development and Redevelopment NPDES #6 — Pollution Prevention and Good Housekeeping for Municipal Operations In addition to these six minimum pollution control measures, NPDES also requires: Compliance with Total Maximum Daily Load requirements for specific pollutants, and Regular program tracking and documentation, success in implementation as determined by water quality monitoring, and annual reporting to Ecology. The federal deadline for seeking NPDES II permit coverage was March 10, 2003. However, many states, including Washington, did not have NPDES II permits available by the March 10, 2003 deadline, and were not in a position to draft individual permits. As a result, many designated permittees in Washington State ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-3 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc were concerned of the legal liabilities if they did not fulfill their federal obligation to apply for a permit by the federal deadline. Accordingly, many communities in Washington, including Kennewick, submitted an Individual Permit Application Ecology by the March 10, 2003 deadline. These Individual Permit Applications were based upon the EPA Individual Permit Application Form. Using these forms, the City detailed its proposed stormwater management program (SWMP) and implementation schedule. In contrast, if the state had developed a General NPDES Permit prior to the March 10, 2003 deadline, then the City would have only had to submit a “Notice of Intent” stating that it wanted to be covered under a General Permit and would comply with the stormwater management program and schedules contained therein. (The March 10, 2003 NPDES II Individual Permit Application for the City of Kennewick has been included as Appendix The Model Municipal Stormwater Program for Eastern Washington (Model Program) details the programs and activities required by NPDES II Permits. The Model Program is complemented by a technical stormwater design manual that was also developed by Ecology and the Steering Committee to meet the unique geologic and hydrologic conditions of Eastern Washington – the Stormwater Management Manual for Eastern Washington. The Model Program provides guidance and general cost information for entities planning for NPDES II compliance, however it explicitly did not include major equipment costs or capital project costs, both of which should be expected, and budgeted for, when implementing an effective stormwater management program under a NPDES II Permit. In addition the Model Program did not address or the presence of threatened or endangered species in receiving waters. It assumed that few existing activities in the “model communities” contributed to NPDES II compliance. As such, with the exception of capital projects and major equipment, most stormwater activity costs shown in the Model Program represent a reasonable estimate of the cost of implementing that activity. However, when using the Model Program as a guide, the assumption behind the cost estimates need to be carefully reviewed. Assumptions about the number of outfalls, the number of required follow-up efforts to eliminate illicit discharges, existence and number of dry-wells, etc. all have a significant impact on estimated costs. Ecology is currently writing a General Phase II Permit for Eastern Washington. The permit was published in draft form in July 2005. Ecology received comments on the draft Preliminary Permit through October 14, 2005. Ecology will now prepare and ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-4 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc seek comment on the Draft Final Permit and expects to issue the final permit in June 2006. After issuance, designated cities and counties will have 60 days to seek coverage under the General Phase II Permit, or seek an Individual Permit. The new General NPDES II Permit will be enforced by the state through the legal authorities established in the federal Clean Water Act and State laws that may include daily fines for violations and third party lawsuits. At the time of General Permit issuance, Kennewick will need to begin complying with the eight special conditions of the Eastern Washington NPDES II permit. Based on the July 2005 draft, the following conditions will have a significant effect on the City:
S1. Permit Coverage – The City of Kennewick is a Primary Permittee. The previously submitted Individual Permit Application may be used in-lieu of submitting a NOI to comply with the new General Permit, at the discretion of the City.
S4. Compliance with Standards – Permittees shall reduce pollutants at existing stormwater discharges “to the maximum extent practicable.” New stormwater discharges will comply with the technical standards in the SWMM for Eastern Washington. The City will need to adopt the SWMM or its local equivalent in meeting this requirement.
S5. Stormwater Management Program for Primary Permittees and Co- Permittees – All permittees, including the City of Kennewick, shall develop and implement a SWMP that will include the six minimum requirements listed above. The SWMP must also have a schedule for implementation and must be updated annually.
S7. Compliance with Total Maximum Daily Load Allocations – The City must comply with all EPA approved At this time, no have been approved or are in the process of being developed that apply to the City of Kennewick.
S8. Monitoring, Reporting and Recordkeeping Requirements – The City must keep records of all required activities and submit annual reports tracking compliance and effectiveness of SWMP implementation. The first annual report is due no later than March 31, 2007, one year after the issuance of the General Permit. In addition, the NPDES permit requires immediate permitting of any un-permitted “Municipal Industrial Sites” that meet Industrial Stormwater permitting criteria. Examples of sites that may need to be considered for permitting include: transportation facilities (buses), road maintenance yards, material storage areas, equipment maintenance facilities, municipal airports, municipal landfills and ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-5 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc transfer stations, municipal quarries and gravel pits, and road maintenance waste management facilities. Permitting any of these facilities requires the development and implementation of Stormwater Pollution Prevention Plans along with other compliance activities including as monitoring and reporting. State/ State/ State/ State/Federal: Federal: Federal: Federal: Underground Injection Control Rule Underground Injection Control Rule Underground Injection Control Rule Underground Injection Control Rule Another significant stormwater law for the City of Kennewick is the Underground Injection Control (UIC) Rule. This rule, as required by the federal SDWA, is intended to protect underground sources of drinking water from contamination by waste fluids, including the infiltration of contaminated stormwater. Ecology and a committee of east-side municipalities, including the City of Kennewick, worked together to draft the State’s new Underground Injection Control (UIC) Rule. The law was completed and adopted February 2006. In addition to the revised UIC Rule, Ecology has also included technical guidance for the use of new stormwater UICs (dry wells and infiltration trenches). This document is entitled the Guidance for UIC Wells that Manage Stormwater, Draft, February 2006(rev.). Under State law, discharges to groundwater can be included in NPDES permits, requiring all of the same controls (i.e. best management practices – BMPs) to be used as for discharges to surface waters. However, at the insistence of stakeholders, Ecology agreed to keep all stormwater UICs out of NPDES II permits and instead will expect that owners of stormwater UICs begin complying with the revised UIC Rule and technical guidance. In general, many of the same management requirements will come into play under UIC as under NPDES, however there will normally be no permit with detailed compliance actions and schedules that are subject to review and enforcement by third parties. Due to the presence of an extensive system of over 2,000 drywells, complying with the UIC Rule will be a significant part of the City’s new stormwater management program. According to this law, the City’s stormwater must meet drinking water and/or groundwater quality standards before it comes into contact with the region’s shallow aquifers. The UIC Rule, as defined by Ecology, allows some flexibility by recognizing that infiltration of stormwater through some types of soils may provide effective treatment. Thus, by the time the infiltrated stormwater meets the top of the most shallow groundwater aquifer, the stormwater is presumed by Ecology to have been treated in the soil to drinking water or ground water quality standards. Ecology’s requirements to provide adequate treatment through soil filtering are further discussed in Section 7. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-6 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc The UIC Rule is not intended to require retrofitting of existing drywells unless they pose a high threat to ground water or create an imminent public health hazard. The City can avoid a formal permit application/award process if they meet certain conditions, or presumptive standards. Instead of a formal permit, Ecology is initially requesting that local agencies with extensive drywell systems — like Kennewick — inventory, map, and register each of their existing dry wells with Ecology. Registered drywells and infiltration trenches must then be “assessed” to determine the level of threat posed to groundwater quality. A retrofit and/or decommissioning program and schedule must be developed for wells deemed a high threat to groundwater quality, or that do not meet core requirements (such as not discharging directly into groundwater). In meeting these requirements the City achieves compliance with Ecology’s presumptive standards. Such an initial risk based drywell assessment has been completed within this study using the best information for regional soil types, groundwater depths, and pollutant loading. Resulting recommendations to improve some of these UIC facilities have been included as part of the CIP discussion presented in Section 7. Ecology’s current proposed approach to the administration of the UIC Rule provides a large element of self-certification during its initial phases. The overall requirements of the UIC Rule are to: Design, construct, and operate new UICs in compliance with Ecology’s presumptive standards, or build an argument that technically demonstrates that other approaches can/should be used and are just as protective as the presumptive standards, Register all new UICs with Ecology before construction, providing supporting information about expected site conditions and pollution management activities, Locate and register all existing UICs with Ecology, providing supporting information about actual site conditions and any pollution management activities, Assess the threat posed by existing UICs to groundwater quality; identify those that present a high threat; and determine a retrofit program and schedule to eliminate the threats (retrofit activity can be structural projects or non- structural programs that reduce pollutant loading), Seek State Waste Discharge Permits for systems that are not considered “Rule Authorized” by Ecology. “Rule authorized” means a UIC well that is registered with the department and meets the nonendangerment standard. Decommission wells that do not meet core standards and cannot be brought up to standards using retrofit programs. These overall requirements can be further defined to identify specific UIC compliance and management program activities: ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-7 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc Requirement #1 Requirement #1 Requirement #1 Requirement #1 — Form an Underground Injection Control Program that includes the following considerations: UIC #1.1 — Locate and map all publicly owned infiltration facilities, collecting site and groundwater information for each UIC facility. Document land uses draining to public drywells. Identify any UICs discharging directly into groundwater, including seasonal high water tables. UIC #1.2 — For new UICs, comply with Ecology’s “presumptive” standards and source control requirements or develop a “demonstrative” regional risk- based strategy for the application of future stormwater infiltration systems based on soils, groundwater, drinking water wells, local pollution management programs, etc. UIC #1.3 — For existing UICs, develop a defensible technical UIC assessment protocol, use this protocol to assess the threat posed to groundwater quality, and identify publicly owned UICs that may create a high risk for ground water degradation by stormwater. UIC #1.4 — For existing UICs, develop a written management and/or replacement strategy (retrofit program) that will reduce pollutant loadings to groundwater by specifically focusing on the systems identified in 1.3 above. UIC #1.5 — Develop any needed UIC management training materials. Requirement #2 Requirement #2 Requirement #2 Requirement #2 — Implement an Underground Injection Control Program that addresses the following requirements: UIC #2.1 — Implement adaptive annual management strategy (UIC # 1.4) for existing high risk systems. To be technically defensible, the management strategy must include projects, monitoring, effectiveness assessment, report preparation, enhanced O&M, source control, spill control/response, and opportunistic retrofits during reconstruction projects. UIC #2.2 — Register all publicly owned infiltration systems, including retrofit program activities and schedules when needed to avoid a “non-Rule Authorized” determination by Ecology. UIC #2.3 — Develop and enforce UIC construction standards (use Ecology Presumptive standards or develop local Demonstrative standards). UIC #2.4 — Perform post-construction pollution management and source control for public systems, provide regular maintenance. UIC #2.5 — Provide ongoing staff training on pollution prevention and proper O&M. UIC #2.6— Conduct monitoring as needed to validate the retrofit program and allow the use of adaptive management. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-8 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc UIC #2.7— Provide reporting to Ecology as needed to illustrate that the retrofit program is being implemented successfully. Note the significant amount of overlap between the Phase II NPDES Permit and activities needed to comply with the UIC Rule. This will be of assistance to the City of Kennewick in developing an overall regulatory compliance strategy and controlling future program costs. Federal: Federal: Federal: Federal: Endangered Species Act Endangered Species Act Endangered Species Act Endangered Species Act Other federal stormwater-related controls that may also affect the City of Kennewick include the Endangered Species Act (ESA), specifically the Section 4(d) stormwater program protection guidelines. While the ESA does not specifically “require” stormwater program activities, it does require that threatened or endangered species not be “taken” (killed or harmed). Threatened and Endangered salmon are the responsibility of the National Marine Fisheries Service (NMFS); Threatened and Endangered trout and other resident fish are the responsibility of the US Fish and Wildlife Service (USFWS). To provide guidance for program managers on how to avoid “take” by their activities, the ESA allows example protective programs to be published under Section 4(d) of the act (known as 4(d) Rule Programs). Stormwater was covered under one of the ESA 4(d) Rule example programs for avoiding the take of salmon. Once again, there is significant overlap between the stormwater activities considered by NMFS and USFWS to be protective of ESA listed species, and those required by the NPDES II Permit and the UIC Rule. Due to this overlap, City staff do not think that ESA Stormwater guidelines will have much effect on the City’s stormwater management plan (Steve Plummer, Personal Communication, 2004). Compliance with the NPDES II and UIC Rule requirements will also generally meet the stormwater guidelines for ESA. The elements of the ESA relating to stormwater (taken from the Stormwater Management Proposal of the Tri-County ESA 4(d) Rule) include the following: ESA 1 — Land use decisions and regulations -Assess stormwater impacts when making land use decisions. Reduce stormwater runoff, impervious surfaces, and retain native vegetation. ESA 2 — Technical Standards - Adopt standards equivalent to Ecology Manual. ESA 3 — Inspection / Enforcement ESA 4 — Maintenance Standards ESA 5 — Source Control - Adopt source control standards within Ecology Manuals ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-9 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc ESA 6 — Illicit Discharge ESA 7 — Public Education ESA 8 — Public Involvement/Outreach ESA 9 — Governmental Coordination ESA 10 — Monitoring ESA 11 — Stormwater Planning ESA 12 — Capital Improvement Program ESA 13 — Habitat Enhancement/Protection ESA 14 — Habitat Acquisition With the exception of ESA Elements # 13 and 14, relating to habitat enhancement, protection and acquisition, the requirements of the six elements of the NPDES II Permit and the remaining 12 elements of the ESA Stormwater requirements are similar. The Tri-County ESA Technical Advisory Committee, chaired by the City of Bellevue, ensured that there was consistency and continuity between NPDES II and ESA State/ State/ State/ State/Federal: Federal: Federal: Federal: NPDES NPDES NPDES NPDES Construction Stormwater General Permit Construction Stormwater General Permit Construction Stormwater General Permit Construction Stormwater General Permit Another aspect of compliance with the Clean Water Act relates to stormwater runoff associated with construction activities. Ecology administers the NPDES Construction permitting program and issues NPDES permits to construction site operators when certain criteria are met. Past guidelines required permits for projects that have 5 or more acres of soil disturbing activities, and discharge stormwater to a receiving water. Receiving waters include wetlands, creeks, unnamed creeks, rivers, marine waters, estuaries, and ditches or storm drains that discharge to a receiving water. Once a site receives an NPDES Construction Stormwater General Permit, due to its potential to discharge to surface waters, any groundwater discharges are also covered by the permit. Phase II of NPDES requires Ecology to begin regulating sites down to 1 acre of land disturbing activity. The new construction permit requires stormwater pollution controls (erosion and sediment BMPs), proper management of construction chemicals and wastes, preparation and implementation of Stormwater Pollution Prevention Plans turbidity/transparency monitoring, and various other pollution management and permit compliance actions. Ecology has finalized the new Construction Stormwater General Permit (CSGP) that will cover construction sites disturbing one acre or more and are discharging into waters of the state. While the permit conditions apply specifically to construction ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-10 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc site operators, it is important for the City to be aware of the new permit conditions because: • There is a lot of overlap between the requirements for contractors under the Ecology Statewide Construction General Permit and the local construction regulatory program, required to be implemented by NPDES II permittees; • Ecology intends to make the local construction regulatory programs of NPDES II Permittees identical to the Statewide Construction General Permit, which would increase the stormwater program requirements for Kennewick; and • Kennewick will need to comply with the new Construction Permit for the construction of its’ own capital improvement projects. Final issuance of the CSGP occurred in November 2005. The following conditions will apply to operators of construction sites that need coverage under the CSGP: • Publish a public notice of construction activities. • Comply with local TMDL and 303(d) listing requirements, if any. • Prepare a outlining BMPs and proposed monitoring activities to control erosion and sediment during construction. • Apply AKART (all known, available, and reasonable methods of prevention, control and treatment) throughout the construction area. • Implement and maintain all BMPs according to the • Keep a site log book. • Conduct regular site inspections. • Conduct turbidity and/or transparency monitoring at discharge locations based on the size of the proposed construction activity. • Keep good records and submit inspection and monitoring reports to Ecology. • Submit Notice of Termination to Ecology upon completion of the project. While these requirements will apply to all construction sites disturbing one or more acre and discharging to surface waters, small site operators (less than 5 acres) located within a Qualified Local (Municipal Stormwater Management) Program are covered under the CSGP without submitting an individual application. Local jurisdictions, such as the City of Kennewick, can become a Qualified Local Program by meeting a series of regulatory requirements. Primarily, the jurisdiction must adopt an erosion and sediment control ordinance or code that is at least as strict as the state’s CSGP requirements. Regardless of local jurisdiction, small construction sites (less than 5 acres of disturbance) in Eastern Washington may qualify for a waiver from the permit requirements if they limit construction to the summer season (June 15 to October ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-11 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc 15) and demonstrate that their Rainfall Erosivity Factor is less than 5 during the construction period. (See the Texas A&M University online rainfall erosivity calculator at http://ei.tamu.edu/ for more information.) A quick calculation using the online calculator shows that this waiver would generally apply to small projects in the City of Kennewick constructed wholly in the summer season. However, it will be up to Kennewick if they will want to allow the use of the Erosivity Waiver (as-is or modified) within their jurisdiction. State: State: State: State: Stormwater Management Manual for Stormwater Management Manual for Stormwater Management Manual for Stormwater Management Manual for Eastern Was Eastern Was Eastern Was Eastern Washington hington hington hington Regulatory compliance of stormwater management in eastern Washington is guided by two technical documents developed by Ecology, the SWMM and the Model Program. The Stormwater Management Manual (SWMM) for Eastern Washington was developed in conjunction with the Model Program. Staff from the City of Kennewick sat on the technical committees that helped Ecology develop the SWMM and the Model Program for Eastern Washington. The Model Program describes the local stormwater programs that need to be implemented to comply with NPDES II permits. The SWMM for Eastern Washington provides the technical guidance on hydrologic analysis, design and operation of stormwater facilities, erosion and sediment control BMPs, and other technical requirements. Adoption and use of the Manual, or an equivalent as approved by Ecology, will be required of all NPDES II permittees. The eight Core Elements of the SWMM for Eastern Washington include: SWMM 1 — Preparation of a Stormwater Site Plan SWMM 2 — Construction Stormwater Pollution Prevention SWMM 3 — Source Control of Pollution SWMM 4 — Preservation of Natural Drainage Systems SWMM 5 — Runoff Treatment SWMM 6 — Flow Control SWMM 7 — Operation and Maintenance SWMM 8 — Local Requirements State/ State/ State/ State/Federal: Federal: Federal: Federal: Wellhead Protection Plan / Program Wellhead Protection Plan / Program Wellhead Protection Plan / Program Wellhead Protection Plan / Program The City’s stormwater management program is an integral part of the City’s water supply program. Due to the extensive use of drywells throughout the City for the disposal of Stormwater, it is critical that the City’s Stormwater Management Program and its Wellhead Protection Program (WHPP) be adequately funded and ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-12 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc implemented on an annual basis. Clearly the WHPP is just as important, if not more important, than the City’s Stormwater Program for sustaining the health of the region’s aquifers through recharge and protection of water quality. The City’s Wellhead Protection Plan requires the development and regular update of the City Wellhead Protection Program that includes: WHPP 1 — Annual inventory of contaminant sources WHPP 2 — Monitoring WHPP 3 — Education of residences and businesses WHPP 4 — Disruption response planning WHPP 5 — Training of key staff WHPP 6 — Supply contingency planning WHPP 7 — Permitting controls WHPP 8 — Design and construction standards WHPP 9 — Hazardous materials handling regulations State State State State Water Quality Water Quality Water Quality Water Quality: Impaired Water Bodies ( Impaired Water Bodies ( Impaired Water Bodies ( Impaired Water Bodies (303(d) 303(d) 303(d) 303(d) List), List), List), List), TMDL TMDL TMDL The State has recently begun an aggressive program to list water bodies and complete Total Maximum Daily Load (TMDL) studies for those water bodies that violate the State’s water quality standards. Certain reaches of the Columbia River, have been listed for temperature and dissolved gases. At this point in time it does not seem likely that the current TMDL studies for the Columbia River will affect the City of Kennewick, or how it is conducting its Stormwater Program. The City of Kennewick is currently not engaged in any TMDL related studies. The reach of the Columbia River next to the City, however, may be the subject of one of these studies in the future. The likely outcome of such a TMDL study could include additional water quality and stormwater related BMP controls for the City of Kennewick, including increased water quality monitoring. These TMDL water quality requirements / enhancements would likely be in addition to those listed in the City’s NPDES II Municipal Stormwater Permit. State State State State Water Water Water Watershed Planning Act shed Planning Act shed Planning Act shed Planning Act The State has also been actively supporting the development of Watershed Management Plans for Watershed Resource Inventory Areas (WRIAs). These plans require all major water resource users and owners to form an advisory committee for each major watershed in the State to evaluate the sources, define the amount and quality, and allocate water resources in each of the watersheds. These plans usually ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-13 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc take years to prepare, with their results often being controversial. They were originally proposed by the State Legislature to help resolve the State’s water resource issues, while also addressing the needs of fish and water quality. The City of Kennewick is actively involved in WRIA #31 Watershed Planning. The WRIA #31 planning unit has conducted its initial assessment for water quality, water quantity, and habitat within the area. Under Phase II of the planning effort, the planning unit will look at Aquifer Storage and Recovery (ASR) in the Kennewick area, which, if implemented, could have implications for the use and management of UICs within the wellhead protection are of the ASR. Additional Stormwater Related Regulations Additional Stormwater Related Regulations Additional Stormwater Related Regulations Additional Stormwater Related Regulations Additional regulations and permits include NPDES permits for wastewater discharges, floodplain management and flood insurance criteria, and various shoreline, land use, and critical/sensitive areas designations, permits and criteria. These other requirements are not the subject of this planning study. Summary of Summary of Summary of Summary of the City’s the City’s the City’s the City’s Existing Existing Existing Existing Regulatory Compliance Activities Regulatory Compliance Activities Regulatory Compliance Activities Regulatory Compliance Activities Preliminary Regulatory Analysis: Preliminary Regulatory Analysis: Preliminary Regulatory Analysis: Preliminary Regulatory Analysis: Documentation of the City’ Documentation of the City’ Documentation of the City’ Documentation of the City’s Existing SWM Program s Existing SWM Program s Existing SWM Program s Existing SWM Program To begin this regulatory analysis, City Staff were interviewed and asked to fill out a Stormwater Regulatory Compliance Questionnaire. The intent of the questionnaire was to document the City’s current stormwater related activities and the City’s state of regulatory compliance. A summary of the results of the staff interviews and questionnaire are presented below, according to the various regulatory compliance requirements. A copy of the questionnaire is included in Appendix F. NPDES II Municipal Stormwater Permit In general, the City: • Rarely reviews the effectiveness of its Stormwater Program, and • Has not identified many local stormwater related needs or costs, action plans, inter-local agreements or additional funding sources. NPDES #1 — Public Education and Outreach • The City does not have an on-going public involvement or education or outreach program for pollution, stormwater or water quality related issues, • Has never developed any brochures or distributed any stormwater information to the public, and ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-14 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc • Has never stenciled any storm drains, created school curriculums, or operated any speakers’ bureaus. NPDES #2 — Public Participation and Involvement • The City, does not routinely conduct public meetings for input, or have news releases, or citizen advisory panels or committees in regard to its stormwater related activities, • However, the City does respond to flooding complaints from the public NPDES #3 — Illicit Discharge Elimination • The City has prepared an outfall map and has an ordinance prohibiting illicit discharges on private properties, however, it • Does not provide training for staff related to illicit discharges. • It has a spill response plan, but no enforcement plan NPDES #4 — Construction Site Pollution Control • The City does not have an erosion ordinance, and • Does not provide training for plan reviewers, however, it does • Review site plans, and • Passes public comments on to the construction site managers. • It also has an onsite inspection program, but • Does not provide training for site operators. NPDES #5 — Post-Construction Surface Water Management • The City does not have an ordinance or permits for construction site operators, • Does not provide BMP training for plan reviewers, • Does not provide inspection of BMPs during construction, and • Does not have a mechanism to ensure ongoing proper maintenance of private BMPs. NPDES #6 — Municipal Operations: Pollution Prevention/Good Housekeeping • The City conducts some annual maintenance planning, but does not prepare an annual comprehensive maintenance plan, • Does not document maintenance activities or have a defined in written O/M plan. • It does however monitor catch basin and drywells cleaning, and • Provides O&M training for city crews. • The City does not have pollution management for all city facilities. • It annually provides street sweeping and catch basin and drywell cleaning and the disposal of wastes. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-15 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc NPDES #7 – Record Keeping, Program Monitoring, Reporting • The City keeps some records of its storm drain maintenance activities, but • Does not have a comprehensive coordinated multi-departmental record keeping program as needed for NPDES compliance, • Does not have a strategy to monitor program implementation or success at achieving goals, and • Does not collect records and prepare annual reports on the stormwater program. NPDES #8 – Compliance with Total Maximum Daily Loads • The City is not currently required to comply with any local stormwater related TMDL compliance activities. . Underground Injection Control (UIC) Rule In relation to drywells and other stormwater infiltration facilities, the City of Kennewick: • Has mapped some publicly owned facilities, • Does not have a risk-based approach for design and location of drywell infiltration facilities, • Has identified those dry wells in high risk areas, per the City’s Wellhead Protection Program, • Has a written plan for reducing pollutant loadings via its drywells, • Does train staff on how to manage drywells in high risk areas, • Does not include monitoring, effectiveness assessment, report preparation, enhanced O&M, source controls, spill response, or opportunistic retrofits, • Has begun locating publicly owned drywells, • Has not registered publicly owned drywells, • Requires design of drywells according to City’s standards, • Does not have pretreatment requirements, • Does not have a pollution prevention plan for the protection of drywells, • Does not have a definition of land draining to individual drywells, • Does not provide comprehensive UIC training for staff, and • Does not have standards for the location of drywells for new construction. ESA Stormwater Section 4(d) Rule The City of Kennewick: • Does not assess stormwater impacts when making land use decisions, • Does not try to reduce stormwater runoff, or reduce impervious surfaces, and retain native vegetation, and • Does not have standards equivalent to the Ecology manual. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-16 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc Water Quality Water quality has not been an area of focus for the City of Kennewick, so the City: • Has not participated in any local TMDL studies, • Does not monitor the water quality of its outfalls, and • Does not have outfalls with a pollutant load allocation. Existing Existing Existing Existing Activities: Activities: Activities: Activities: NPDES II Municipal Stormwater Permit NPDES II Municipal Stormwater Permit NPDES II Municipal Stormwater Permit NPDES II Municipal Stormwater Permit The City of Kennewick has made the commitment to comply with the General NPDES II Municipal Stormwater Permit for eastern Washington. In meeting this commitment, the City responded to and met the initial requirement by completing and submitting a Permit Application to Ecology before the required March 10, 2003 due date. A summary of the City’s NPDES II Individual Permit Application is presented in Table 6-1, and the complete version is included in Appendix F. The stormwater regulatory compliance activities listed in Table 6-1 are the minimum requirements for the City to achieve compliance with the state’s General NPDES II Permit for eastern Washington. They are defined in terms of water quality Best Management Practices (BMPs), as listed in the federal register (1999) and defined in Ecology’s Draft NPDES II Permit (July, 2005). In order to be in compliance, the City will need to implement and fund eighteen different BMPs during the course of the next five years. This is referred to by Ecology as meeting the six minimum requirements. Many of these activities are new for the City and will likely require new ordinances and legal authorities, as well as additional staff, equipment, and financial resources. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-17 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc Table 6 Table 6 Table 6 Table 6-1 Summary of City’s March 2003 NPDES II Summary of City’s March 2003 NPDES II Summary of City’s March 2003 NPDES II Summary of City’s March 2003 NPDES II Permit Application Permit Application Permit Application Permit Application Requirement #1 Requirement #1 Requirement #1 Requirement #1 Public Education and Outreach Public Education and Outreach Public Education and Outreach Public Education and Outreach City shall develop and implement a stormwater education and outreach strategy. BMP 1(a) — Develop and implement a stormwater education and outreach strategy. Requirement #2 Requirement #2 Requirement #2 Requirement #2 Public Participation and Involvement Public Participation and Involvement Public Participation and Involvement Public Participation and Involvement City shall implement a public involvement/participation program in compliance with State and Local public notice requirements. BMP 2(a) — Hold public meetings and solicit public review of the Stormwater Management Plan. Requirement #3 Requirement #3 Requirement #3 Requirement #3 Illicit Discharge Elimination Illicit Discharge Elimination Illicit Discharge Elimination Illicit Discharge Elimination City shall:
Develop a storm sewer map, showing the location of all outfalls and the names and location of all waters of the US & State that receive discharges. (Done)
Prohibit by ordinance non-stormwater discharges to the storm drain system. (Done)
Develop and implement an illicit discharge detection plan.
Inform employees, businesses and general public of the hazards of illegal discharges. BMP 3(a) — Create a storm sewer system map showing all known storm drain outfalls to receiving waters. BMP 3(b) — Develop and enforce an ordinance prohibiting illegal discharges and illegal dumping and authorizing enforcement actions, including on private property. BMP 3(c) — Develop an illicit discharge detection plan. BMP 3(d) — Visually inspect all known outfalls during dry weather. BMP 3(e) — Develop and implement a spill response plan. BMP 3(f) — Develop and implement an enforcement plan to ensure compliance with local ordinances. BMP 3(g) — Provide training opportunities for staff on proper BMPs for spills and illicit discharges. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-18 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc Table 6 Table 6 Table 6 Table 6-1 (cont.) (cont.) (cont.) (cont.) Summary of City’s March 2003 NPDES II Permit Application Summary of City’s March 2003 NPDES II Permit Application Summary of City’s March 2003 NPDES II Permit Application Summary of City’s March 2003 NPDES II Permit Application Re Re Re Requirement #4 quirement #4 quirement #4 quirement #4 Construction Site Pollution Control Construction Site Pollution Control Construction Site Pollution Control Construction Site Pollution Control City shall develop and implement procedures for site inspection and enforcement of control measures, and for the receipt and consideration of information submitted by the public. BMP 4(a) — Adopt an ordinance for erosion and sediment controls for operators disturbing one acre or more. BMP 4(b) — Provide training opportunities for plan reviewers and field inspectors in erosion and sediment control. BMP 4(c) — For all construction sites greater than one disturbed acre, review site plans to ensure that erosion and sediment controls and post-construction controls are included and are in accordance with local ordinance. BMP 4(d) — Publish a phone number, or equivalent system, to receive public input on construction site runoff issues. BMP 4(e) — Inspect all construction sites greater than one disturbed acre during the construction period that are regulated by the local ordinance adopted in BMP 4(a). BMP 4(f) — Provide information on erosion and sediment control training opportunities to construction operators. Requirement #5 Requirement #5 Requirement #5 Requirement #5 Post Post Post Post-Construction Surface Water Construction Surface Water Construction Surface Water Construction Surface Water Management Management Management Management City shall:
Develop, implement and enforce a regulatory program to address runoff from new development and redevelopment projects that disturb one or more acres.
Develop and implement strategies that include BMPs appropriate to the community and ensure maintenance of same. BMP 5(a) — Adopt an ordinance requiring post development runoff controls. BMP 5(b) — Develop and implement a plan to address post-construction runoff controls during the plan review, construction inspection and post-construction maintenance process. Require submittal of BMP maintenance requirements. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-19 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc Table 6 Table 6 Table 6 Table 6-1 (cont.) (cont.) (cont.) (cont.) Summary of City’s March 2003 NPDES II Permit Application Summary of City’s March 2003 NPDES II Permit Application Summary of City’s March 2003 NPDES II Permit Application Summary of City’s March 2003 NPDES II Permit Application Requi Requi Requi Requirement #6 rement #6 rement #6 rement #6 Municipal Operations: Pollution Municipal Operations: Pollution Municipal Operations: Pollution Municipal Operations: Pollution Prevention/Good Housekeeping Prevention/Good Housekeeping Prevention/Good Housekeeping Prevention/Good Housekeeping City shall develop and implement a municipal O&M plan and training. BMP 6(a) — Develop and implement a municipal O&M Plan addressing the following:
Park and open space maintenance pollution prevention and good housekeeping.
Vehicle and equipment washing.
Dust control practices.
Catch basin cleaning and stormwater system maintenance pollution prevention and good housekeeping.
Structural stormwater control pollution prevention and good housekeeping.
Deicing and snow removal pollution prevention and good housekeeping for roads and parking lots.
Flood management project evaluation and review procedures.
Employee training. Requirement #7 Requirement #7 Requirement #7 Requirement #7 Annual Reporting and Record Keeping Annual Reporting and Record Keeping Annual Reporting and Record Keeping Annual Reporting and Record Keeping City shall provide regular record keeping and reporting as requested by Ecology. BMP 7(a) — Provide record keeping and reporting, as required by Ecology, including:
Status of compliance with permit.
Assessment of progress in achieving measurable goals.
Results of information collected, monitoring data.
Summary of stormwater activities planned for next report.
Any changes in measurable goals or practices.
Notice of reliance with other agencies to achieve objectives. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-20 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc Existing Activities: Existing Activities: Existing Activities: Existing Activities: Underground Injection Control ( Underground Injection Control ( Underground Injection Control ( Underground Injection Control (UIC) Rule UIC) Rule UIC) Rule UIC) Rule The City has already begun activities to be in compliance with the UIC Rule by locating, inventorying, and mapping more than 2,000 public owned dry wells throughout the City. The remaining UIC requirements will be included in the City’s overall Regulatory Compliance Strategy/Program that will be developed during this stormwater planning study. The UIC compliance activities will be integrated with the City’s other regulatory obligations and included in a master program of prioritized activities and implementation timeframes. Compliance with the other seventeen UIC requirements will likely require additional staffing and an increased annual funding allocation. Existing Activities: Existing Activities: Existing Activities: Existing Activities: Endangered Species Act (ESA) Endangered Species Act (ESA) Endangered Species Act (ESA) Endangered Species Act (ESA) As stated earlier, City staff do not expect the stormwater requirements of Section 4(d) to be an issue for the City, if the City achieves compliance with the NPDES II Municipal Stormwater Permit and the UIC Rule. As a result, few additional resources should need to be allocated to achieve compliance with the stormwater guidelines of ESA. Existing Activities: SWMM for Eastern Washington Existing Activities: SWMM for Eastern Washington Existing Activities: SWMM for Eastern Washington Existing Activities: SWMM for Eastern Washington The City’s Standard Specifications provide design standards for the construction of new infiltration facilities, as described in Chapter 5 – Storm Drain. Section 5-9 also addresses post construction stormwater runoff with the following requirements: • Commercial sites and private streets shall be designed to retain and dispose of a 10-year, 24-hour storm on-site. • Residential subdivisions shall be designed to retain and dispose of the 25-year, 24-hour storm, with allowance for overflow of the 10-year, 24-hour natural state storm where conditions allow. • Drywells, perforated pipe systems, and other means of infiltration may be used, where there is no potential for groundwater contamination. • Detention Ponds use is restricted (See Section 7 of this report). • Retention ponds may only be used with prior approval from the City Engineer. • The City does not assume ownership or maintenance of any storm drainage facilities associate with commercial development or retention ponds in residential areas. Guidance for the location of adequate sites for new infiltration facilities is not addressed in the Standard Specifications. A copy of Chapter 7 has been included in Appendix A. NPDES requires that the SWMM for Eastern Washington or an equivalent set of ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-21 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc standards be adopted by the City. The Draft NPDES Permit includes minimum technical standards for Development and Redevelopment that refer directly to the SWMM. The City’s codes will have to be reviewed and updated as needed. The SWMM for Eastern Washington has design criteria for new development and redevelopment projects, as well as guidance in the preparation, and implementation of stormwater site plans and projects, source control activities, erosion and sediment controls, and ongoing maintenance of BMPs. The manual addresses water quality by recommending eight Core Elements (previously listed) for managing stormwater runoff. The City of Kennewick will need to carefully review their current codes and design standards and make changes to ensure consistency with the NPDES II Permit and the SWMM for Eastern Washington. The City believes that their current set of stormwater design standards meets and/or exceeds the guidance set forth in Ecology’s Manual for Eastern Washington (Steve Plummer, Personal Communication, 2004). It is recommended, however, that the City document its current set of Standard Specifications for addressing stormwater and submit these to Ecology to establish “equivalency” with the SWMM for Eastern Washington. If equivalency is approved by Ecology, the City may refer developers, engineers, and contractors to their requirements rather than the Eastern Washington Manual, or the UIC technical guidance. While some of the City’s standards likely exceed those in the SWMM for Eastern Washington, it is likely that the City will need to make changes in other areas to ensure consistency and equivalency with the Ecology’s SWMM. Other Existing Other Existing Other Existing Other Existing Regulatory Regulatory Regulatory Regulatory Activities Activities Activities Activities Wellhead Protection Plan/Program - The City developed its Wellhead Protection Plan in 1997. They have adopted the Plan and annually fund elements of the resulting Wellhead Protection Program (WHPP). The WHPP should be considered to be an element of the City’s overall Stormwater Program. Water Quality, 303(d), TMDL, Allocation Plans – The City is not currently participating in any local water quality studies that may result in future stormwater related requirements. Watershed Planning Act – The City of Kennewick is actively involved in WRIA #31 Watershed Planning. The majority of the city population is located within this WRIA. The WRIA #31 planning unit has conducted its initial assessment for water quality, water quantity, and habitat within the area. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-22 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc Under Phase II of the planning effort, the planning unit will look at Aquifer Storage and Recovery (ASR) in the Kennewick area, which, if implemented, could have implications for the use and management of UICs. All planning efforts are ongoing and are expected to be finished in 2007. Additional Stormwater Related Regulations – No changes in the City’s current approach to flood control, flood plain management, sensitive areas, land use/GMA, or other stormwater related regulations are anticipated at this time. (City staff, Personal Communication, 2004) Regulatory Compliance Strategy Regulatory Compliance Strategy Regulatory Compliance Strategy Regulatory Compliance Strategy The following regulatory compliance strategy has been developed to help the City come into compliance with the various federal, state, regional and local surface water, groundwater, water quality, and habitat-related requirements discussed in this section. A preliminary assessment, focusing on the six minimum requirements of the NPDES II permit, was conducted early in this study. A summary of the recommended comprehensive regulatory compliance program is presented below. A more detailed analysis is included in Appendix D. Method of Analysis Method of Analysis Method of Analysis Method of Analysis As noted in the above discussion, there is significant overlap between the six minimum requirements of the NPDES II General Permit, the requirements of the State’s Underground Injection Program, and the fourteen stormwater guidelines of the Endangered Species Act. Ecology’s guidance documents, the Model Program for Eastern Washington and the SWMM for Eastern Washington, provide some clarification on how to achieve regulatory compliance in Eastern Washington, along with the current Preliminary Draft of the NPDES II Permit for Eastern Washington (July, 2005). A regulatory compliance “gap analysis” was performed by first comparing the City’s existing Stormwater Program to the six minimum requirements of the NPDES II Municipal Permit. The City first was given credit for its existing stormwater program activities and current levels of staffing, funding, equipment, ordinances, and technical expertise. Then, gaps between the minimum requirements and the existing stormwater program were identified. Next, the requirements of the NPDES II Permit were compared with the fourteen requirements of the Underground Injection Control Rule. The same was done between the NPDES II Permit and the fourteen requirements of the Endangered Species Act. Any additional requirements from the UIC Rule and ESA were compared against existing city programs and ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-23 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc additional gaps were identified. After all the gaps were identified, a list of additional stormwater related activities and resources needed for compliance was assembled. This list includes additional staffing, maintenance activities, financial analysis, equipment purchases, programs, ordinances, and policies needed to “fill the gaps” between the City’s existing stormwater program and regulatory requirements. The list of activities and resources needed for compliance is based on the guidance provided within the Model Program for Eastern Washington, and the Preliminary draft NPDES II Permit. The model program includes both required and recommended activities for small and large cities. Based on population, the City of Kennewick will likely need the activities for a large city (population greater than 50,000). This analysis also looked for potential efficiencies and ways to fill multiple gaps with a single activity, policy, or resource. Finally, an action plan was assembled to help the City fund and implement the needed changes over the next five years. Summary of Problems and Needs Summary of Problems and Needs Summary of Problems and Needs Summary of Problems and Needs A three-part regulatory compliance gap analysis is presented in Appendix D. Part I summarizes the City’s existing stormwater program as described in Section 5. Part II is the preliminary assessment completed early in this study to review the anticipated NPDES II Permit Requirements. Part III is the detailed regulatory compliance “gap” analysis using the methodology described above. The Part III assessment analyzes each of the permits described in this section and recommends activities, staffing levels, and associated costs (beyond the City’s existing program) needed to meet the requirements of those permits. The program activities and BMPs are based on the recommendations of the Model Program for Eastern Washington and were updated as needed to reflect the language of the July 2005 Preliminary Draft General NPDES II Permit. A summary of the recommendations is included in Table 6-2. The table shows the required labor hours and costs for each of the program elements averaged over the first 5 years of the permit, as well as the total hours that will be needed when the program is fully implemented in Year The funding required is based on meeting the full program needs in Year A more detailed analysis with a breakdown of individual tasks and the yearly funding requirements is included in Appendix D. A financial plan is presented in Section 9. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-24 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc The main findings in this regulatory gap analysis are: • The City is likely to need approximately 3.4 FTE in the Municipal Services Department at an additional annual cost of about $600,000 to achieve full regulatory compliance by Year 5 of the program. This more than doubles the existing staffing and staff funding levels. • NPDES may also increase the workload of staff in other departments (Community Planning Department) as they must participate in NPDES compliance activities such as development and adoption of policies and standards, and implementation of enhanced development review, inspection/enforcement, and record keeping. Covering the cost of additional development review activities may require changes to development permit fees. • NPDES compliance alone will likely require 3.2 additional FTE at an additional annual cost of about $450,000 per year. • The City’s public education program needs improvement. A formal education strategy and implementation plan is needed to begin distributing stormwater information to the public and to business owners. • Cost savings could be realized by combining the general stormwater education plan with the City’s UIC education responsibilities. UIC education should include a strong component focused on business owners in high risk industries and should be coordinated with the wellhead protection program. • The City will need a formal program to solicit public comment on the proposed stormwater program and a plan to formally receive, document, and respond to stormwater complaints. • A phone number should be assigned to solicit stormwater input from the public. The same number could also be used to receive any complaints related to construction activity. Combining these two program elements would satisfy NPDES II. • The City needs an ordinance relating to erosion and sediment control for construction sites disturbing one or more acres. The City should evaluate the 1 acre minimum threshold to determine if it is suitable for use or if other, lower thresholds are needed to address the types of development, slopes, and soils unique to Kennewick. Many communities already regulate sites disturbing less than 1 acre. Exempting all developments below an acre in size from erosion and sediment controls or post-construction stormwater BMPs should be carefully considered and cross-checked with other City policies and requirements. • Municipal stormwater quality monitoring is not needed at this time. However, the Ecology’s construction stormwater general permit requires turbidity and/or transparency monitoring for construction sites. In addition, Ecology may require NPDES II permittees to require and oversee construction site runoff monitoring as part of their construction regulatory program. ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-25 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc Insert Table 6-2, page 1 of 2, landscape 11x17 ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-26 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc Insert Table 6-2, page 2 of 2, landscape 11x17 ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-27 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc • The City’s stormwater management development ordinance(s) needs to be updated and standards need to be enhanced to match: the minimum technical requirements for development and redevelopment in the final NPDES II permit; the SWMM for Eastern Washington (construction and post-construction stormwater control BMPs), the presumptive standards of the final Determination of Treatment and Source Control Requirements for UIC Wells in Washington State (or locally developed demonstrative standards). • Training will be needed to educate City staff and plan reviewers on the new ordinances and design standards. Training for local contractors could be included in the overall public education program. • The City’s previous efforts to locate illicit discharges are a good step toward compliance. However, a formal plan is needed for detection, screening, and response to illicit discharges. Illicit discharge education for local businesses should be included in the public education program. The City needs to modify existing codes or develop a new ordinance that meets the specific requirements of the NPDES II requirements. • The City’s existing maintenance and operation program likely meets the regulatory requirements for storm drains. However, the current activities and policies need to be documented into a formal O&M manual. In addition, NPDES requires that other City operations and maintenance activities be examined, and modified as needed, to protect water quality. Examples include grounds keeping, parks, road maintenance, etc. • UIC compliance will likely require an additional 0.25 FTE at an additional annual cost of $354,000 annually if implemented in conjunction with NPDES II programs. The 5-year average UIC Water Quality Capital project cost is estimated at about $329,000 per year beginning in 2006 (See Section This would bring the total additional UIC program cost to about $354,000 per year. • The City needs to continue efforts to locate, assess, and register publicly owned drywells. • The City needs to develop a formal plan to identify, monitor, retrofit, and/or decommission high-risk UICs. An initial plan and recommendations have been developed with this study and are included in Section 7 of this report. • The City needs to decide if it will use the Ecology presumptive design and site suitability standards for new UICs or if it will develop risk-based demonstrative standards. If the latter approach is used, then the City needs to develop the demonstrative standards and document the technical basis for choosing the standards. The UIC site analysis work in Section 7 can be built upon to develop demonstrative standards and a risk based management approach. • Activities needed for ESA compliance are similar to those of the NPDES II ---PAGE BREAK--- Section 6 — Regulatory Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 6-28 otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 6.doc permit. No additional activities or BMPs should be needed beyond the NPDES II requirements to address the stormwater guidelines of Section 4(d) of ESA. • No additional activities are needed for water quality 303(d) and TMDL compliance at this time. • While the current program does not dedicate equipment to stormwater maintenance, the existing agreement to share equipment between departments satisfies the maintenance needs and provides overall cost savings. The City needs to dedicate budget for repair and replacement of aging maintenance equipment. • Formal record keeping and program monitoring is needed to document each year’s stormwater activities and submit annual reports to Ecology. A detailed program review will be needed at the end of Year to evaluate the program and recommend modifications for the next permit cycle. • Additional costs associated with capital projects related to stormwater and UIC systems are discussed in Section 7. • Annual and total costs are presented in Section 9, along with an annual implementation plan that meets the interim milestones and due dates prescribed in the draft General NPDES II Municipal Stormwater Permit for eastern Washington. Full compliance with the General NPDES II Permit is achieved at the end of the five year permit planning process. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-1 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Introduction Introduction Introduction Introduction This section presents the development of a Capital Improvement Program (CIP) to address existing and future drainage infrastructure needs throughout the City of Kennewick. The CIP includes projects to address two areas of concern: system deficiencies in capacity and water quality concerns related to aquifer recharge. System deficiencies are determined based on hydrologic and hydraulic modeling that identifies locations of current surcharge and locations where the existing system may be undersized for future flow conditions. A short description of the modeling effort is described below with more detailed information provided in Appendix G. A list of the CIP projects to address system capacity deficiencies follows the modeling discussion. A summary table of all CIP projects is presented in Table 7-5 along with a cost summary and a long term schedule for implementation. Descriptions and sketches of each of the projects along with detailed cost estimates follow the summary table. Areas of water quality concerns were determined based on a review of existing facilities in Section 4 and analysis of the City’s underground injection control (UIC) systems presented at the end of this section. The UIC treatment analysis identifies high risk areas and methods for retrofitting or decommissioning existing drywells. This analysis, along with the list of CIP projects to address water quality in underground discharge systems provide the basis for the City to develop a UIC Program that will meet the regulatory compliance requirements described in Section 6. The CIP projects to address water quality are also included in Table 7-5 with the cost summary and long term implementation schedule. Together, the system deficiency projects and water quality projects form the CIP program to address existing and future stormwater infrastructure needs in the City of Kennewick. This program along with the regulatory compliance activities presented in Section 6 will require additional staffing and funding to develop a comprehensive surface water management plan. The overall funding needs and a discussion of potential funding opportunities and strategies are presented in Section 8. Hydrologic and Hydraulic Hydrologic and Hydraulic Hydrologic and Hydraulic Hydrologic and Hydraulic Modeling Modeling Modeling Modeling Introduction to Modeling Introduction to Modeling Introduction to Modeling Introduction to Modeling A hydrological and hydraulic model (H&H model) of the City of Kennewick’s stormwater collection system was constructed to aid in the assessment of hydraulic capacity limited portions of their system. The focus of the model is on problem areas that are currently prone to flooding and other areas that may be prone to flooding in the future. The H&H model was created using geographic information system (GIS) ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-2 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc mapping generated from CAD and stormwater system inventory information obtained from the City of Kennewick. Hyetographs and standards from the Department of Ecology’s Stormwater Management Manual for Eastern Washington, September 2004 were used to predict stormwater runoff from the modeled area for the 25- and 100-year storm events. Runoff from these events was used to identify hydraulic capacity limited portions of the stormwater collection system, and then compared to areas of known flooding as identified by City staff. A future condition scenario was also modeled to assess surcharge areas due to full build-out of the existing UGA and develop recommendations for improvements required to reduce potential surcharge. The City of Kennewick chose HYDRA as their modeling software to analyze their stormwater collection system in an effort to combine modeling expertise from their developed sanitary sewer model, also completed using HYDRA. The electronic framework for the City’s infrastructure was developed in ArcGIS and then transferred into HYDRA for analysis and computation. The results of the model were transferred back into ArcGIS to create the visual products and maintain the storm database. Additional background and details of the HYDRA model, along with information on the ArcGIS interaction are discussed in Appendix G. Model Input Data Model Input Data Model Input Data Model Input Data Stormwater system database files were developed in GIS mapping to represent the City of Kennewick’s collection system (links and nodes) and the drainage area (basins). These files were exported from GIS to database files formatted for use with HYDRA. A brief description of the model input data follows. More detailed information about individual components of the HYDRA model is provided in Appendix G. System Inventory System Inventory System Inventory System Inventory A system inventory GIS database has been collected by the City of Kennewick. This database was used as the basis for developing the H&H model. The system inventory includes spatial documentation of the physical features of the stormwater system, including pipes, culverts, open channels, manholes, drywells, and catch basins. When the data necessary to construct a complete H&H model was not available in the system inventory, a typical value was assumed and entered in the GIS database layer. The assumed information can easily be replaced in the system inventory GIS database as new information becomes available. The H&H model’s focus is on stormwater mainlines and drainage way capacity to handle the existing and future growth within the City. Branches of the conveyance ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-3 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc network without a defined upstream sub-catchment were not included in the model. Therefore, areas of localized flooding due to inlet capacity and local infrastructure issues may not be addressed in the model. Modeled elements are shown in Figure 7- 1. Basins Basins Basins Basins As described in Section 3, the City is divided into 17 major drainage basins. Drainage sub-basins for each of these major basins were delineated using a combination of aerial topography and previous delineations provided by the City. Subbasins were further delineated to account for future conditions without adding additional basins. Approximately 970 sub-basins were modeled ranging from approximately 3 to 600 acres as shown in Figure 7-2. The basins are used to calculate runoff and estimate the stormwater flow that enters the drainage collection network. The aerial topography provided by the City of Kennewick was used in developing the drainage basin attributes. Analysis of these maps in GIS was conducted to delineate basin and sub-basin boundaries, determine watercourse alignments and tributary flow paths, measure sub-basin geometric properties, estimate routing parameters for open channels, and calculate basin time lag parameters. Land Use Land Use Land Use Land Use The initial modeling scenario looked at the existing level of development and associated land use throughout the project area. Existing land use is considered to be the development as of 2004. Modeling assumptions are based on the City’s current zoning shape files and a 2003 aerial photo. The land use assumptions used in the existing conditions model are shown in Figure 7-3. A second model scenario looked at the 20-year build-out for the City of Kennewick. In order to look forward with the model, the sub-basins were analyzed in conjunction with the comprehensive zoning map for areas of potential growth. Potential growth was determined by comparing existing developed conditions reflected in the existing system analysis to the buildable areas remaining within the UGA. Based on the amount of buildable area remaining in each sub-basin and imperviousness percentage estimates for the comprehensive zoning, new amounts of imperviousness were estimated and a new CN value was calculated for the future sub-basins in the model analysis. Figure 7-4 graphically reflects the increased percentage for imperviousness for the future conditions in the model. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-4 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Stormwater Runoff Stormwater Runoff Stormwater Runoff Stormwater Runoff Stormwater Runoff within each sub-basin was developed using the SCR TR-55 methodology. Curve numbers, impervious area, time of concentration, and lag time were calculated as described in Appendix G. Hydrographs were developed for local rainfall conditions of the 24-hour SCS Type IA storm for both the 25-year and 100-year events, based upon criteria of the SWMM for Eastern Washington. Under Region 2 (Central Basin), it’s recommended that the SCS Type 1A Hyetograph for long duration storm events be used for storm water runoff evaluation. These storm events would be characterized as occurring typically in the winter and spring season in the Mid-Columbia. The manual suggests a separate hyetograph for the short duration high intensity storm that Kennewick typically experiences during the summer and fall seasons. For analysis of the Comprehensive Plan, the long duration storm event was modeled. An example rainfall intensity for these events is shown in Figure 7-5. Each hyetograph was set up in 30-minute increments within HYDRA. 24-hour rainfall is 1.6 inches for the 25-year storm event and 2.0 inches for the 100-year storm event. If required, the short duration storm event can also be modeled for specific areas throughout the City to see the specific effects on the storm drainage system. Figure 7-5 Hydrograph 25-Year The locations where runoff from the basins, or sub-catchments, enters the conveyance system were defined by adding the identification of each corresponding node as an attribute to each sub-catchment. The “inlet” node for each sub-catchment was generally selected near the middle to upper portion of the basin. The estimated ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-5 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc runoff from the 25-year 24-hour storm event was used for predicting areas of surcharge. The 100-year 24-hour storm event analyzed additional areas of concern the City may choose to address as well. Irrigation Canals Irrigation Canals Irrigation Canals Irrigation Canals The model assumes that existing discharges will be maintained into existing irrigation canals. There are numerous locations across the City’s UGA where the irrigation tail water combines with stormwater run-off (Zintel Canyon, Garfield Canyon, Elliot Lake, etc.). There are also numerous locations where storm run-off discharges directly or sheet flows into irrigation canals during large storm events. Some these cross-connections were identified in Figure 4-4. The necessary infrastructure to completely separate storm run-off flows from irrigation canals would be a tremendous undertaking by the City. For this reason, the future model did not separate flows between irrigation canals and City owned conveyance. Capaci Capaci Capaci Capacity Problems / Model Analysis ty Problems / Model Analysis ty Problems / Model Analysis ty Problems / Model Analysis The results of the HYDRA 6.3 model analysis can be used in conjunction with GIS mapping to visualize the problem areas of the stormwater collection system. This is shown in Figures 7-6a and 7-6b. The 25-year storm event was used as the basis of analysis to identify these potential over capacity areas within the storm drainage system. For the existing system flows and predicted future flows, values of energy grade line (EGL) were utilized in determining the locations where the water surface elevation may be overtopping the ground surface elevations. The results of EGL were recorded in HYDRA and transferred into the GIS database files so they could be mapped across the City. Since HYDRA is a one-dimensional unsteady flow hydraulic model, it does not predict the extent of flooding over a two- or three-dimensional surface. However, the EGL can be representative of problem areas, whether they are a minor surcharge or a larger area of inundation. Locations where the EGL is greater than ground surface elevations represent where there is potential flooding in roadways or the inundation of adjacent properties. In other words, it indicates that the capacity of the stormwater conveyance system under a properly maintained system is insufficient to convey peak flows through these areas. Comparison to Existing Concern Areas Comparison to Existing Concern Areas Comparison to Existing Concern Areas Comparison to Existing Concern Areas Nodes and links with EGL above the ground elevation were identified and compared to the areas of known flooding discussed in Section 4 as “major maintenance areas.” The results did not agree completely with the areas of concern identified in Figure 4- 4. However, they did confirm two areas of concern that where previously ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-6 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc recommended capital improvement projects under the JUB Comprehensive Flood Control and Storm Water Drainage Plan (1990) that still need to be completed (indicated in Figure 4-5). The first is the pipeline in Garfield St. and the second is the need for a regional retention basin located in the vicinity of 27th Ave. and Gum St. Areas of concern shown in Figure 4-4 appear to be local ponding conditions that result from poorly graded or settled pavement, inlet capacity, or maintenance needs of mainline pipe and drainage ways. This is important to the City because the model results indicate that problems in these areas can be solved with relatively simple solutions and are not indications of larger systemic problems with stormwater mainline capacity or surcharging. Future Conditions Future Conditions Future Conditions Future Conditions The simulation results for the 20-year build-out for the City of Kennewick had similar results as those for existing conditions. In general, the future conditions model shows pipes reaching greater capacity and several areas of increased ponding. Improvement projects are identified based on these future flow conditions. The future conditions model did not separate flows between irrigation canals and City owned conveyance. However, this report does recommend that the City, as a policy, not allow any new discharges into irrigation drainage ways and continue to take advantage of separating flows on an opportunity basis with the development and redevelopment of areas within the City. Gutter Flow Gutter Flow Gutter Flow Gutter Flow A maximum allowable flow depth in gutters was considered also. A flow depth up to 4 inches was considered not to be a conveyance capacity concern. If flow depth was greater than this, then it was reflected as a potential problem area. The model is not currently predicting a problem under the existing flow conditions, but three gutter flow concerns under future flow conditions are shown in Figure 7-6c. Model Identified Improvement Projects for System Deficiencies Model Identified Improvement Projects for System Deficiencies Model Identified Improvement Projects for System Deficiencies Model Identified Improvement Projects for System Deficiencies Figure 7-6d identifies the locations of the proposed improvement projects to correct system deficiencies identified by the HYDRA model. Conveyance projects (C1 - C4) are identified in the Capital Improvement Plan portion later in this Section. Proposed projects are based on reducing system surcharge under the future conditions, 25-year storm event. CIP projects have been incorporated into the HYDRA model to verify that the proposed pipes will flow at 85% of capacity or lower under future flow conditions. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-7 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Several problem areas identified in the model were not recommended for improvement projects at this time for specific reasons. The Conway Canyon area near South Kellogg Street is already identified as an improvement project area by the City and is planned for construction of final leg of the drainage way through that basin. This should alleviate any residual localized ponding in that area. Two other problem areas (along S. Ely St. and on Clearwater Ave., west of Columbia Center Blvd) have been recommended as maintenance watch and observation areas. These are locations that were identified as potential problem areas in the model, but the City staff has no record of surcharging or flooding occurring in those areas. The City should consider these potential problems for future surrounding development, but not necessarily design and construct infrastructure improvements without confirmation the model results in the field. The final area identified on Figure 7-4d is the Vista Field area. These conveyance problems were identified in the model for future development in the Vista Field. However, assuming that the City maintains its current policy of requiring private developments to retain the 10 year storm on-site, this should mitigate future capacity issues in the public storm system. Once again, the City should consider this in future development plans for the commercial land in those basins. Water Quality Analysi Water Quality Analysi Water Quality Analysi Water Quality Analysis Introduction to Water Introduction to Water Introduction to Water Introduction to Water Quality Quality Quality Quality Human activity and storm runoff from the land contribute nutrients, organic matter, and silt that affect water quality. The EPA identifies sources of pollutant discharge under a “point” or “nonpoint” classification. Point sources are cultural in origin, usually pipes from sewage treatment plants, stormwater discharges, or industry. They are defined in federal regulations as “any discernable, confined and discrete conveyance, including but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, containers… from which pollutants are or may be discharged.” Agricultural stormwater discharges and return flows from irrigated agriculture are excluded from the definition of point source. Non-point sources are far more difficult to assess quantitatively and to control, and are generally related to non site-specific discharge. Numerous studies have been conducted regarding the type and quantity of non-point source pollutants found in stormwater. In general, non-point source pollutants include: • Runoff from roads and highways contains pollutants from vehicles. Typical pollutants in road runoff include: oil and grease, polynuclear aromatic hydrocarbons (PAHs), lead, zinc, copper, cadmium, sediments (soil particles), road salts, and other anti-icers. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-8 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc • Runoff from industrial areas contains heavy metals, sediments, and a broad range of man-made organic pollutants, including phthalates, PAHs, and other petroleum hydrocarbons. • Runoff from commercial areas contains road-based pollutant runoff, and may also contain other pollutants typical of industrial and/or residential areas. • Residential areas contribute road-based pollutants to runoff, as well as herbicides, pesticides, nutrients (from fertilizers and animal wastes), bacteria, viruses, and other pathogens (from animal wastes). After a rain event, these pollutants can be carried into surface waters affecting the habitat, hydrologic patterns and elevating pollutant concentrations and loadings. The highest concentrations of contaminants often are associated with the “first flush” discharge. This occurs from an initial storm runoff experienced after a prolonged dry period. Thus, the pollutant accumulation in intense small runoff events can be more detrimental to water quality than larger flooding events. Because of this, upstream management practices, which control small volumes of initial runoff, can be very effective in enhancing nonpoint source pollutant removal. The Washington State Department of Ecology (DOE) and the Stormwater Mangement Manual for Eastern Washington (SMMEW) attempt to address these sources of pollution through a presumptive approach using Best Management Practices for Stormwater Management (BMPs). That is, providing accepted technically sound stormwater management practices that, when used, are presumed to protect water quality and instream habitat – and meet the stated environmental objectives of the regulations. Project proponents do not have to follow the guidance outlined in the SWMM for Eastern Washington when handling storm runoff. However, each individual project must demonstrate that their development will not adversely impact water quality by collecting and providing appropriate supporting data to show that their alternative approach satisfies state and federal water quality laws. Because of this, the majority of project proponents will choose to develop under the presumptive approach outlined in the SWMM for Eastern Washington rather than spend the additional time and money in research and study of their project’s impact on water quality. A detailed discussion of various Water Quality BMPs is included as Appendix H. The City of Kennewick employs a number of water quality facilities that match the presumptive stormwater management practices suggested by the SMMEW throughout its stormwater system in providing non-point source pollutant control. However, the primary method of water quality treatment for the City is through the use of Underground Injection Control (UIC) facilities, as shown by its more than 2000 City-owned and maintained dry-wells. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-9 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Underground Injection Control nderground Injection Control nderground Injection Control nderground Injection Control This section documents a planning level review of the City’s UIC Facilities. UIC treatment requirements are described in depth in Chapter 5 of the SWMM for Eastern Washington and the Guidance for UIC Wells that Manage Stormwater, Draft (February 2006, rev). This analysis looks at pollutant loading, predicted soil infiltration rates, average depth to seasonal groundwater, and presumed soil treatment capacities in order to development UIC Pretreatment Requirements for the City of Kennewick. The UIC pretreatment requirements are shown in Figure 7- 7a. This map is intended to be used as a planning level tool for the City to provide guidance and input to City-wide CIP planning, drainage basin planning, development and project review, and conceptual and preliminary design input. UIC Treatment Analysis UIC Treatment Analysis UIC Treatment Analysis UIC Treatment Analysis Tables 7-1 through 7-3 (excerpted from the statewide UIC guidance document) provide a basis for the UIC analysis. Details of the analysis and supporting Figures 7-7b through 7-7e are included below. The evaluation and analysis is limited to accuracy of its generalized data and assumptions. Proponents of proposed UIC facilities should verify site conditions and conduct their own site specific analysis to determine the suitability and pretreatment requirements associated with their facility. Figure 7-7b, Pollutant Loading Classification for UICs, depicts the pollutant loading for areas across the City. Designations for pollutant loading vary from insignificant to high depending on the zoning, land use, and vehicular traffic associated with the area. The majority of the City has a low pollutant loading designation because of the large residential make-up of the City. However, the City does have a large commercial component in the Columbia Center area, the historic downtown region, and along the Clearwater and Hwy 395 corridors. Table 7-2 provides a general description of the pollutant loading designations. Figure 7-7c, Predicted Soil Infiltration Rates, provides generalized look at the infiltration characteristics of the soils throughout the City. The data used to generate the map was derived from the SCS, July 1971, Soil Survey for Benton County Area and historic infiltration rates from the City of Kennewick’s development records. Because the UIC facilities are concerned with infiltration capabilities of the soil at depths of 5 to 15 feet for constructed drywells, the SCS infiltration data was generalized from the subsurface strata, greater than ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-10 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Table 7 Table 7 Table 7 Table 7-1 Treat Treat Treat Treatment capacity of vadose zone materials (subsurface geologic matrix below the facility and ment capacity of vadose zone materials (subsurface geologic matrix below the facility and ment capacity of vadose zone materials (subsurface geologic matrix below the facility and ment capacity of vadose zone materials (subsurface geologic matrix below the facility and above an unconfined aquifer) for removing solids, metals, and oil from stormwater discharged above an unconfined aquifer) for removing solids, metals, and oil from stormwater discharged above an unconfined aquifer) for removing solids, metals, and oil from stormwater discharged above an unconfined aquifer) for removing solids, metals, and oil from stormwater discharged to UIC facilities. to UIC facilities. to UIC facilities. to UIC facilities. (For use with Tables 7-2 and 7-3) Presumed treatmen Presumed treatmen Presumed treatmen Presumed treatment capacity t capacity t capacity t capacity and conditions and conditions and conditions and conditions Description of vadose zone layer Description of vadose zone layer Description of vadose zone layer Description of vadose zone layer HIGH HIGH HIGH HIGH In order for the facility to be considered for exemption from the pre-treatment requirement, a minimum thickness of six feet of these materials must be naturally present between the bottom of the UIC structure and the top of the highest known seasonal water table. * Materials with average grain size <0.125mm or having a sand to silt/clay ratio of less than 1:1 and sand plus gravel less than 50% Materials with hydraulic conductivity less than 10-3 cm/s Lean, fat, or elastic clay Sandy or silty clay Silt, loess Clayey or sandy silt Sandy loam or loamy sand Silt/clay with inter-bedded sand Well-compacted, poorly-sorted materials This category includes till, hardpan, and caliches MEDIUM MEDIUM MEDIUM MEDIUM In order for the facility to be considered for exemption from the pre-treatment requirement, a minimum thickness of ten feet of these materials must be naturally present between the bottom of the UIC structure and the top of the highest known seasonal water table.* Materials with average grain size 0.125mm to 4mm or having a sand to silt/clay ratio between 1:1 and 9:1 and percent sand greater than percent gravel Materials with hydraulic conductivity from 10-3 to 10-1 cm/s Fine, medium or coarse sand; silty sand Sand with inter-bedded clay and/or silt Poorly-compacted, poorly-sorted materials This category includes some alluvium and outwash deposits LOW LOW LOW LOW In order for the facility to be considered for exemption from the pre-treatment requirement, a minimum thickness of twenty five feet of these materials must be naturally present between the bottom of the UIC structure and the top of the highest known seasonal water table. Materials with average grain size >4mm to 64mm or having a sand to silt/clay ratio greater than 9:1 and percent sand less than percent gravel Materials with hydraulic conductivity from 10-1 to 1 cm/s Poorly-sorted, silty or muddy gravel Sandy gravel, gravelly sand, or sand and gravel This category includes some alluvium and outwash deposits NO NO NO NONE NE NE NE Materials with average grain size >64mm or having total fines (sand and mud) less than 5% Materials with hydraulic conductivity greater than 1 cm/s Well-sorted or clean gravel Boulders and/or cobbles Fractured rock This category includes fractured basalt, other fractured bedrock, and cavernous limestone * See the narrative in Section 4.4.5 of Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State for possible exceptions to the thickness requirement. Note that this table does not address the matrix within which the facility is constructed, nor does it address the entire depth of the vadose zone below the bottom of the facility. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-11 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Table 7 Table 7 Table 7 Table 7-2 2 2 2 Pollutant loading cla Pollutant loading cla Pollutant loading cla Pollutant loading classifications for solids, metals, and oil in stormwater runoff directed to UIC ssifications for solids, metals, and oil in stormwater runoff directed to UIC ssifications for solids, metals, and oil in stormwater runoff directed to UIC ssifications for solids, metals, and oil in stormwater runoff directed to UIC facilities. facilities. facilities. facilities. (For use with Tables 7-1 and 7-3) Pollutant loading Pollutant loading Pollutant loading Pollutant loading classification classification classification classification Proposed land use or characteristics of the area Proposed land use or characteristics of the area Proposed land use or characteristics of the area Proposed land use or characteristics of the area contributing runoff to the UIC facility contributing runoff to the UIC facility contributing runoff to the UIC facility contributing runoff to the UIC facility * INS INS INS INSIGNIFICANT IGNIFICANT IGNIFICANT IGNIFICANT Impervious surfaces not subject to motorized vehicle traffic or application of sand or deicing compounds Un-maintained open space LOW LOW LOW LOW Inside Urban Growth Management Areas, fully controlled and partially controlled limited access highways with ADT** less than 15,000 and other roads with ADT less than 7,500 vehicles per day Outside Urban Growth Management Areas, all roads with ADT** less than 15,000 vehicles per day Parking areas with <40 trip ends** per 1,000 SF of gross building area or <100 total trip ends Other land uses with similar traffic/use characteristics (e.g. most residential parking and employee-only parking areas for small office parks or other commercial buildings) MEDIUM MEDIUM MEDIUM MEDIUM Inside Urban Growth Management Areas, fully controlled and partially controlled limited access highways with ADT** between 15,000 and 30,000 vehicles per day and other roads with ADT between 7,500 and 30,000 vehicles per day Outside Urban Growth Management Areas, all roads with ADT** between 15,000 and 30,000 vehicles per day Parking areas with between 40 and 100 trip ends** per 1,000 SF of gross building area or between 100 and 300 total trip ends Primary access points for high-density residential apartments Intersections controlled by traffic signals that do not meet the definition of a high-density intersection (see Glossary) Transit center bus stops Other land uses with similar traffic/use characteristics (e.g. visitor parking for small to medium commercial buildings with a limited number of daily customers) HIGH HIGH HIGH HIGH All roads with ADT** >30,000 vehicles per day High-density intersections (see definition in the Glossary) Parking areas with >100 trip ends** per 1,000 SF of gross building area or >300 total trip ends On-street parking areas of municipal streets in commercial and industrial areas Highway rest areas Other land uses with similar traffic/use characteristics (e.g. commercial buildings with a frequent turnover of visitors, such as grocery stores, shopping malls, restaurants, drive- through services, etc.) * See also Chapter 3 - Prohibitions and Sections 4.1 – Treatment Requirements to Preserve Infiltration Rates, and 4.4.1 – Special Treatment Requirements for Solids, Metals, and Oil of Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State; all prohibitions and special treatment requirements still apply. **Average daily traffic counts and trip ends must be calculated for twenty years following completion of the project and may be determined using “Trip Generation” published by the Institute of Transportation Engineers. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-12 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Table 7 Table 7 Table 7 Table 7-3 Matrix for determining suitability of subsurface discharge of stormwater from Matrix for determining suitability of subsurface discharge of stormwater from Matrix for determining suitability of subsurface discharge of stormwater from Matrix for determining suitability of subsurface discharge of stormwater from commercial and residential land uses to new UIC facil commercial and residential land uses to new UIC facil commercial and residential land uses to new UIC facil commercial and residential land uses to new UIC facilities without structural pre ities without structural pre ities without structural pre ities without structural pre- treatment to remove solids, metals and oil. treatment to remove solids, metals and oil. treatment to remove solids, metals and oil. treatment to remove solids, metals and oil. (For use with Tables 7-1 and 7-2) All project proponents should read the entirety of the Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State for exceptions or other requirements that apply in certain situations. Appropriate pre-treatment technologies must be selected using the information provided in Ecology’s stormwater management manuals. Treatment Treatment Treatment Treatment capacity capacity capacity capacity Pollutant Pollutant Pollutant Pollutant loading loading loading loading High Medium Low None Insignificant Suitable for all UIC facilities Suitable for all UIC facilities Suitable for all UIC facilities Suitable for all UIC facilities Low Suitable for all UIC facilities Suitable for all UIC facilities Suitable for all UIC facilities Pretreatment required to remove solids 4 Medium Suitable for two- stage drywells 2 Suitable for two- stage drywells 2 Pretreatment required to remove solids 4 Pretreatment required to remove solids 4 High 1 Pretreatment required to remove oil 3 Pretreatment required to remove oil 3 Pretreatment required to remove oil and solids 3,4 Pretreatment required to remove oil and solids 3,4 1 Note that the prohibitions listed in Chapter 3 of Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State and any special treatment requirements. 2 A two-stage drywell includes a catch basin or other pre-settling/spill control structure that traps small quantities of oils and solids. The catch basin or other pre-settling/spill control device must be inspected and cleaned regularly (see the operation and maintenance requirements in Ecology’s stormwater management manuals). Any special treatment requirements in this chapter still apply. 3 Treatment to remove oil means oil control as defined in the SMMEW. 4 Treatment to remove solids means basic treatment as defined in the Glossary. Removal of solids should remove a large portion of the metals in most stormwater runoff. Any special treatment requirements in this chapter still apply. For low pollutant loading sites, implementation of appropriate source control BMPs may be employed in lieu of structural treatment BMPs (see Ecology’s stormwater management manuals). ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-13 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc 5 feet when available. These assumed soil infiltration rates were then associated with SCS soils type and supplemented by measured infiltration rates from the City’s records. Table 7-4 provides a listing of soil types and the assumed sub-surface infiltration rate used for the analysis. Table 7 Table 7 Table 7 Table 7-4 Soil Infiltration Assumptions Used for Planning Documents Soil Infiltration Assumptions Used for Planning Documents Soil Infiltration Assumptions Used for Planning Documents Soil Infiltration Assumptions Used for Planning Documents Soil Name Soil Name Soil Name Soil Name Hydrologic Group Hydrologic Group Hydrologic Group Hydrologic Group Treatment Treatment Treatment Treatment Capability Capability Capability Capability Permeability (in/hr) Permeability (in/hr) Permeability (in/hr) Permeability (in/hr) BURBANK A Low 10.0 BURKE C High 1.7 ELLISFORDE B High 0.5 ESQUATZEL B High 1.2 FINLEY B Medium 3.5 HEZEL B High 0.5 KENNEWICK B High 0.5 KIONA B Medium 1.7 KOEHLER C High 7.0 PASCO C Medium 10.0 PITS A Low 20.0 PROSSER C Low 5.0 QUINCY A Low 15.0 RITZVILLE B High 1.7 RIVERWASH D Low 20.0 SCOOTENEY B Medium 4.0 SHANO B Medium 1.7 STARBUCK D Medium 1.7 WAMBA D Low 20.0 WARDEN B Medium 1.7 WILLIS C High 0.8 Figure 7-7d, Average Depth to Seasonal Groundwater, is a groundwater depth contour map that predicts areas within the City of high seasonal groundwater based upon information from a calibrated groundwater model that was developed by Golder. Using ArcGIS, the map is a color coded and contour representation of the difference in height between the predicted groundwater surface from Golder’s model and a digital elevation model of the ground surface for the City of Kennewick. There are areas within the City that were not included in Golder’s model and, therefore, not included in the average depth to groundwater map for the City. In these areas, depth to groundwater was assumed to be adequate and UIC Pretreatment Requirements were determined solely on pollutant loading and soil treatment capacity. One area of concern is the commercial zone in the vicinity of Clearwater ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-14 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Ave. and I-82. This area’s UIC pretreatment requirements could vary based upon depth to groundwater from those shown based upon field measurements. Figure 7-7e, Presumed Treatment Capacity, is a result of the analysis of the soil types and infiltration characteristics of the vadose zone used for water quality by the City’s UIC facilities and the average depth to seasonal groundwater map as prescribed by Table 7-1. This figure and Figure 7-7b, are used to determine the UIC Pretreatment Requirements, Figure 7-7a, with the criteria provided in Table 7-3. Of note, the typical drywell within the City of Kennewick ranges from 10 to 15 feet in depth. The required vadose zone depth to achieve adequate treatment is measured from the bottom of the UIC facility and seasonal high groundwater table. For the analysis an average drywell depth of 11 feet was assumed in determining sufficient soil depth for treatment. UIC Analysis Results UIC Analysis Results UIC Analysis Results UIC Analysis Results Figure 7-7a, UIC Pretreatment Requirements, provides the results of the UIC treatment analysis. In general, the areas shown as “No Pretreatment Required” occur in low pollutant loading areas with sufficient soil treatment capacity. These areas allow drywell construction that meets the basic design requirements without required pretreatment of storm runoff. “2-Stage” pretreatment is the lowest level of storm runoff pretreatment that provides capturing of sediments and some oil prior to discharge at the UIC. Pretreatment of oil, solids, or both occur with higher pollutant loading and insufficient soil treatment capacity. The City’s 10-year aquifer recharge zone for the Ranney Wells in Columbia Park poses a challenge for allowing water quality treatment through subsurface infiltration in that zone. The risks associated with allowing direct discharge of potential contaminants into the groundwater through UIC facilities are great when acknowledging that the Ranney Wells produce a significant portion of the City’s water supply. Although Figure 7-7a shows areas within the aquifer recharge zone where no pretreatment is required, this report recommends that 2-Stage treatment be the minimum treatment standard for all drywells in the aquifer recharge zone. For areas of higher traffic loading and commercial and industrial zoning within the aquifer recharge zone, we recommend that future storm runoff be piped in a tightline system to be discharged at sufficient location. In areas where it is not feasible to tightline stormwater to a sufficient discharge location, pretreatment for both oils and solids should be required for each UIC. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-15 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Water Quality Recommendations Water Quality Recommendations Water Quality Recommendations Water Quality Recommendations Recommendations for water quality improvements set forth in this Storm Water Management Plan are primarily based upon implementation of the “6-minimum control measures” as set forth in the EPA Phase II Stormwater Regulations. Specific recommendations for BMPs for water quality include: Source Controls Source Controls Source Controls Source Controls Implement management and good housekeeping practices through programs of public education, public awareness, and public involvement. Industrial and commercial property owners should be required to protect potential pollutant sources from rainfall and/or storm water runoff. The City’s street sweeping and vacuuming program should be continued in its current form, at a minimum, to minimize wind blown sediments and heavy metal deposits from motor vehicles from being suspended and washed during the first flush of storm events into infiltration facilities and City-owned drywells. In the future, the City may conduct an analysis of their street cleaning program to determine streets and locations within the City where the most material and highest concentration of pollutants are collected and restructure the frequency of cleaning accordingly. Restructuring could also take into account other factors of proper cleaning frequency, such as infiltration facilities in aquifer recharge zones or where runoff discharges into sensitive areas. This could potentially streamline the program to move resources in areas over maintained to areas under maintained. Infiltration Facilities Infiltration Facilities Infiltration Facilities Infiltration Facilities Infiltration drywells, infiltration trenches, and infiltration ponds that are fully drained (dry) following a storm runoff event are recommended. Evaporation ponds could be used for regional facilities but are discouraged because of aesthetics, odor from stagnant conditions, maintenance, etc. Infiltration though drywells and infiltration trenches should be implemented on all residential, commercial, and/or industrial projects whenever feasible. When subsurface conditions prevent complete disposal of storm water, infiltration with subsurface collection and transport to the storm sewer system is recommended. Direct inlets to infiltration facilities without the use of a collection sump, catch basin, or sedimentation facility to reduce suspended solids should be avoided. Retention Facilities Retention Facilities Retention Facilities Retention Facilities Retention facilities have been, and will continue to be, the preferred form of treatment for the City with a requirement for developers to retain the entire 10 year post-developed storm event for the project area. Typically, residential developments have satisfied this requirement through a combination of retention storage ponds ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-16 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc and/or infiltration dry-wells. An area that has been historically overlooked by the City is the volume and conveyance of overflow for the private retention facilities. Future overflow events should be considered by development engineers to ensure facility failure or storms greater than 10 years return frequency. Overflow routes should be designated and evaluated to avoid environmental damage through erosion and scouring as well as damage to adjacent land owners and/or City owned facilities. Constructed wetlands are considered retention facilities and should only be used for regional facilities. Filtration Filtration Filtration Filtration Above ground filtration is recommended to provide primary pollutant removal in conjunction with landscape management plans to direct stormwater runoff into facilities that are easily maintained and inspect. Facilities such as bio-filtration swales and filter strips can be creatively incorporated into landscaping for most commercial, industrial, and residential developments and provide a basic level of treatment for the majority of stormwater pollutants. Catch Basins Catch Basins Catch Basins Catch Basins Catch basins are a treatment device for reduction of sediment and floatable materials in storm water. In areas susceptible to oil contamination, including high use roadways, gas stations, commercial parking lots, and industrial sites, catch basins should be fitted with a hooded outlet. Catch basins should always be installed upstream of subsurface infiltration facilities to reduce sedimentation and pollutant loading. Additionally, catch basins should be fitted with a spill control separator upstream of any subsurface infiltration facility to reduce the impact of spilled petroleum products and contaminants. Detention Facilities Detention Facilities Detention Facilities Detention Facilities Detention Facilities should only be used in instances when retention and infiltration facilities are unfeasible. Project proponents must ensure that discharge from the detention facility does not adversely impact the corridor in terms of scouring, erosion, or conveyance capacity by conducting a analysis for the project. The facilities should be used to provide temporary storage of surface water runoff to reduce peak flows from developed areas. Underground storage tanks, vaults, or pipes should only be used if sufficient space is not available for pond storage, or if the pond would not fully drain following a storm runoff event. Oil/Water Separators Oil/Water Separators Oil/Water Separators Oil/Water Separators Oil/water separators should only be used in “extreme-elevated” areas when source control options are unavailable. “Extreme-elevated” areas include bulk fuel handling, gas stations, and areas handling large volumes of fuel and/or oil products. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-17 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Existing Facility Existing Facility Existing Facility Existing Facility Recommendations Recommendations Recommendations Recommendations Zintel Canyon – Conway Canyon – Family Fishing Pond: No water quality treatment modifications are proposed for the facilities in this drainage system. Although the system drains a large developed area, the detention time and vegetation in the existing systems should provide a significant level of pollutant removal prior to discharge into the Columbia River. Duffy’s Pond: The retention of storm runoff in the Corps ditches and Duffy’s Pond most likely allows time for sedimentation of suspended solids in the runoff and time for natural nutrient removal in a wetpond oriented water quality facility. Without water quality monitoring data, any evaluation of the adequacy of treatment would be purely speculative. Garfield Ditch: While previous studies have identified this ditch as a potential CIP to tightline the drainage system, this report recommends maintaining the ditch, and enhancing the pollutant removal capacity through continued maintenance. The ditch should be analyzed to confirm flow velocities during large storm events. Modifications may be necessary to enhance the swale’s capacity and reduce flow velocity so that velocities during storm events do not resuspend pollutants. Frog Pond: Technically, Ecology’s UIC criteria do not apply for the Frog Pond because it is not a Class V Underground Injection Well. However, the Frog Pond potentially discharges untreated storm runoff through an infiltration facility with questionable subsurface water quality treatment. Elliot Lake: Similar to Duffy’s Pond, Elliot Lake most likely provides a significant level of water quality treatment through sedimentation and nutrient removal through the long residence time of water. No modifications are currently recommended. However, the mixing of City runoff with KID irrigation water at the discharge location poses a potential problem. If future water quality data indicates pollutant problems with the discharge, it would be difficult to determine which portion of the water quality problem is the City’s and which portion is KID’s. Columbia Park: Potential water quality issues exist with the adequacy of pollutant removal in the park ditch and combined pollutant loading from Highway 240. Future projects in this area will need to incorporate Ecology’s current water quality treatment requirements. Amon Creek: The current pollutant loading from City owned and controlled runoff is relatively minor. No modifications are currently recommended. All future ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-18 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc development in this basin should apply the BMPs from the SWMM for Eastern Washington. Columbia Center R/D Facility: The facility is designed to retain and treat water quality runoff storms and overflow larger events No modifications are currently recommended. Capital Improvement Plan Capital Improvement Plan Capital Improvement Plan Capital Improvement Plan Introduction to CIP Introduction to CIP Introduction to CIP Introduction to CIP The Capital Improvement Program (CIP) is organized in to two components: conveyance system deficiencies and water quality improvements. Table 7-5 provides an overview of the CIP with projected costs and suggested implementation schedule. System deficiency projects address ponding or flooding problems in the City’s storm drainage system. Water quality improvement projects address areas where existing water quality facilities do not meet the treatment requirements outlined in the SWMM for Eastern Washington and pose a potential risk to surrounding water resources. Projects recommended to correct system deficiencies have been determined through historical records, staff information, and comprehensive modeling. As described earlier, the CIP projects address capacity and conveyance issues for the trunklines and not areas of localized ponding that may occur during storm events. The design of conveyance projects is based on providing capacity for the 25-year storm under future land use conditions. The proposed projects have been incorporated into the HYDRA model to ensure that capacity is not adversely affected by each project. The current NPDES Phase II requirements (and Core requirements outlined in the SWMM for Eastern Washington) allow permittees to follow a presumptive approach for runoff treatment based on approved BMPs to treat stormwater. However, in the future, water quality monitoring at the City’s discharges to surface water may be required to validate the presumptive approaches used within the stormwater system. Deficiencies discovered through monitoring would likely require additional CIP projects, beyond what is described here, to improve treatment at the City’s discharge locations. The following pages document each of the proposed CIP projects. Figures showing problem areas and proposed solutions are included along with tables with planning- level cost estimates. The HYDRA model reports ponding as areas of surcharge, where the energy grade line is above the rim elevation of a given structure. In the ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-19 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Table 7 Table 7 Table 7 Table 7-5 City of Kennewick Storm Drainage System City of Kennewick Storm Drainage System City of Kennewick Storm Drainage System City of Kennewick Storm Drainage System Improvement Program Improvement Program Improvement Program Improvement Program - Budget and Schedule Budget and Schedule Budget and Schedule Budget and Schedule 200 [PHONE REDACTED] - 202 [PHONE REDACTED] million) million) million) million) Project Code Project Code Project Code Project Code Improvement Improvement Improvement Improvement Project Project Project Project Type * Type * Type * Type * Drywell Drywell Drywell Drywell Retro/Removal Retro/Removal Retro/Removal Retro/Removal Storm Pipe Storm Pipe Storm Pipe Storm Pipe Install Install Install Install Estimated Estimated Estimated Estimated Cost in 2006 Cost in 2006 Cost in 2006 Cost in 2006 dollars dollars dollars dollars (millions) (millions) (millions) (millions) 200 [PHONE REDACTED] 2008 2008 2008 2008 2009 2009 2009 2009 2010 2010 2010 2010 2011 2011 2011 2011 2012 2012 2012 2012 2013 2013 2013 2013 2014 2014 2014 2014 2015 2015 2015 2015 2016 2016 2016 2016 2017 2017 2017 2017 2018 2018 2018 2018 2019 2019 2019 2019 2020 2020 2020 2020 2021 2021 2021 2021 2022 2022 2022 2022 2023 2023 2023 2023 2024 2024 2024 2024 2025 2025 2025 2025 2026 2026 2026 2026 Capital Capital Capital Capital Improvements Improvements Improvements Improvements Project costs are escalated from 2005 at 4 percent per year. See Tables 7-6 through 7-11 for individual cost estimate breakdowns. Amount Unit Amount Unit Cost Cost Cost Cost Notes Notes Notes Notes Conveyance Improvements Conveyance Improvements Conveyance Improvements Conveyance Improvements C1 N. Edison Storm Drainage Improvements DC 840 LF 0.101 0.149 C2 S. Garfield St. Storm Drainage Improvements DC 900 LF 0.284 0.091 0.209 C3 W. Columbia Dr. & N. Garfield St. Drainage Imp DC 1,415 LF 0.170 0.215 Water Quality Improvements Water Quality Improvements Water Quality Improvements Water Quality Improvements AQ1 Aquifer Recharge Zone Drywell Retrofit WQ 297 EA 1.050 [2,3] 0.098 0.102 0.106 0.111 0.115 0.120 0.125 0.129 0.135 0.140 0.146 0.151 AQ2 W. Columbia Dr. Drywell Removal WQ 12 EA 4,300 LF 0.610 0.401 0.417 AQ3 W. Kennewick Ave. Drywell Removal WQ 6 EA 2,800 LF 0.393 0.425 AQ4 S. Vancouver St. & W. 10th Ave. Drywell Removal WQ 21 EA 783 LF 0.110 0.129 AQ5 S. Ely St. & W. 10th Ave. Drywell Removal WQ 34 EA 5,400 LF 0.807 [2,4] 1.104 AQ6 Vista Way Drywell Removal WQ 1 EA 430 LF 0.061 0.063 AQ7 W. 27th Ave. & Hwy 395 Drywell Removal & Facility WQ 34 EA 4,150 LF 0.675 [2,5] 0.263 0.274 0.285 Total Capital Improvement Total Capital Improvement Total Capital Improvement Total Capital Improvement Projects: Projects: Projects: Projects: 4.26 .26 .26 .26 0.154 0.154 0.154 0.154 0.6 0.6 0.6 0.633 33 33 33 0.098 0.098 0.098 0.098 0.495 0.495 0.495 0.495 0.380 0.380 0.380 0.380 0.610 0.610 0.610 0.610 0.516 0.516 0.516 0.516 1.641 1.641 1.641 1.641 0.125 0.125 0.125 0.125 0.279 0.279 0.279 0.279 0.135 0.135 0.135 0.135 0.140 0.140 0.140 0.140 0. 0. 0. 0.146 146 146 146 0. 0. 0. 0.151 151 151 151 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 Notes: Costs are planning level estimates and conceptual in nature. Costs generated by using available City of Kennewick bid tabulations and applying a 30% contingency. Pipe construction costs are based on an average $140/LF that includes all restoration and contingencies. Drywell retrofit and/or removal is based on Table 7-11 and 7-11 with assumptions listed. It is assumed that there are, on average, 2.2 catch basins connected directly to each public drywell to obtain retrofit cost. $50,000 added to project cost to cover outfall construction. $93,600 added to project cost to cover water treatment with standard contingencies and design. * Project Type Codes: WQ Water Quality Project DC Deficiency Correction ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n _-20 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc This page intentionally left blank ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-21 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc following figures, the ponding is graphically depicted by a circle of 100 foot diameter for each foot of surcharge. For example, a 250 foot circle represents 2.5 feet of surcharge. System Deficiencies System Deficiencies System Deficiencies System Deficiencies Project C1 Project C1 Project C1 Project C1- N. Edison Storm Drainage Improvements N. Edison Storm Drainage Improvements N. Edison Storm Drainage Improvements N. Edison Storm Drainage Improvements The model has predicted flooding and capacity problems along N. Edison Street at the intersection of Okanogan. City staff have not documented any severe flooding at the intersection, however, nuisance ponding has been observed. Most likely, runoff is being attenuated along the local streets and yards during large storm events. The local streets (Metaline, Fillmore and Okanogan) maintain a sub-standard road cross- section with no curb and gutter. When the City of Kennewick decides to install a standard residential cross section through routine maintenance and replacement, the modeled capacity problem is likely to increase in frequency and severity. Figure 7-8a shows the predicted flooding in the model for a 25-year storm event. The modeled ponding does not appear to pose an imminent threat to property damage. The recommended solution is to increase inlet capacity at the intersection of Okanogan and N. Edison and increase the size of the conveyance line in North Edison to 15 inches. As shown in Figure 7-8b, the improvement would add a large capacity inlet grate (unless street improvements through Okanogan included a sufficient collection system). The project would also upsize of 840 LF of 12-inch storm drainage pipe to 15-inch diameter. Because of the limited scale of this project, the construction of this improvement should be considered in conjunction with any planned utility or street improvements along the corridor, not as a stand-alone project. A detailed cost analysis is included in Table 7-6 for the N. Edison storm drainage improvements. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-22 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-23 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-24 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Table 7-6 DATE: 3/21/2006 1 1 L.S. MOBILIZATION $ 3,074 $ 3,074.00 2 1 L.S. SPILL PREVENTION & COUNTER MEASURE PLAN $ 500 $ 500.00 3 1 L.S. TRAFFIC CONTROL $ 10,000 $ 10,000.00 4 850 L.F. PAVEMENT TRENCH RESTO. ACP,9" ROCK) $ 30 $ 25,500.00 5 2 EA. CONNECT TO 48" STD STORM MANHOLE $ 500 $ 1,000.00 6 850 L.F. TRENCH, EXCAVATION, & BACKFILL $ 12 $ 10,200.00 7 840 L.F. 15" STORM DRAIN PIPE $ 14 $ 11,760.00 8 840 L.F. IMPORTED PIPE BEDDING $ 2 $ 1,680.00 9 840 L.F. TRENCH SAFETY SYSTEMS $ 1 $ 840.00 NOTE: SUBTOTAL 64,554 $ CONTINGENCY 30% 19,366 $ 3. Assumes Manholes are reusable. WSST - $ 4. Costs based on COK Miscellaneous Storm Drainage, Contract P0402-04. ENG/ ADMIN 20% 16,784 $ TOTAL 100,704 $ PROJECT DESCRIPTION: N. EDISON ST., CANAL TO W. OKANOGAN AVE. STORM LINE REPLACEMENT ENGINEER'S OPINION OF PROBABLE COST 2. Assumes a 6 FT. deep trench. N. EDISON ST. STORM CONVEYANCE IMPROVEMENTS 1. Not a revenue producing project, no sales tax. TOTAL COST ITEM NO. ITEM DESCRIPTION QUANTITY UNIT UNIT PRICE ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-25 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Project C2 Project C2 Project C2 Project C2 - S. Garfield St. Storm Drainage Improvements S. Garfield St. Storm Drainage Improvements S. Garfield St. Storm Drainage Improvements S. Garfield St. Storm Drainage Improvements The model has predicted flooding and capacity problems along S. Garfield St. between W. 19th Ave. and W 14th Ave. Approximately 1050 acres of Garfield Canyon Basin is tributary to the roadside ditch along S. Garfield St. The ditch flows to the north and accepts flow from storm drainage lines extending from Park Hills and S. Garfield St. near the intersection of W. 14th Ave. At W. 13th Ave., the roadside ditch flows into a maintained vegetated swale for approximately 900 LF. At W. 10th Ave, the flow enters a 36-inch storm drain line that discharges to the regional infiltration pond along W. 10th Ave. (Frog Pond). In addition, an overflow pipe from the nearby irrigation canal directs water to the S. Garfield St roadside ditch when the canal is operating at a high stage. The cross connection has a low point in the middle of W. 14th Ave. that floods when the roadside ditch is inundated with runoff and the irrigation canal is conveying water at a high stage. City staff have documented overtopping of the roadside ditch along S. Garfield St. and minor flooding at the intersection of W. 19th Ave. Figure 7-9a shows the predicted flooding for a 25-year event, without accounting for the canal overflow. The high flow events appear to generate surcharging into the storm system at the base of Park Hills that may be the cause of documented minor flooding. A reduction in the surcharging along S. Garfield St. may alleviate this problem. The City has elected to move forward with improves and has begun design on a new 36 inch storm drainage culvert from the intersection of S. Garfield St. and W. 10th Ave. to the intersection of S. Garfield St. and W. 16th Ave. In addition, the City will install a new stormwater culvert in W. 14th Ave. to remove the failing stormline. Figure 7-9b shows the recommended improvement of installing approximately 1500 LF of 36-inch storm drainage pipe. The City’s estimated The City’s estimated The City’s estimated The City’s estimated cost of the project cost of the project cost of the project cost of the project is is is is $284,000 $284,000 $284,000 $284,000. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-26 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-27 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-28 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Project Project Project Project C3 C3 C3 C3 – W. Columbia Dr. & N. Garfield St. Drainage Improvement W. Columbia Dr. & N. Garfield St. Drainage Improvement W. Columbia Dr. & N. Garfield St. Drainage Improvement W. Columbia Dr. & N. Garfield St. Drainage Improvement The model has predicted flooding and capacity problems along W. Columbia Dr. and N. Garfield St. As shown in Figure 7-10a, the existing 8-inch diameter storm drainage pipes convey approximately 70 acres of storm runoff to the Corps ditch that parallels the Columbia River Levee. Heavy surcharging of the conveyance pipes, as well as ponding on the collection system is predicted during the 25-yr storm event. Ponding during storm events has been observed by City staff. However, the magnitude of the flooding has not been documented. Similar to improvements suggested on N. Edison, storm run-off is likely being attenuated along the sub- standard residential streets that make up the majority of the tributary area. As with Project C1, improvements to the conveyance system should be constructed in conjunction with the scheduled replacement of the local residential streets to standard residential cross-sections with curb and gutter. At this time, improvements to the City streets in this area are not scheduled. The recommended improvements to the storm system consist of upsizing the 925 LF of 8-inch diameter storm lines in W. Columbia Dr. to 18 inches and the upsizing the 490 LF of 12-inch diameter conveyance line in N. Garfield to 24 inches. The new pipe would maintain the same discharge location to the Corps ditch along the Columbia River Levee. Figure 7-10b shows the recommended CIP. Table 7-7 outlines the estimated costs of the project. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-29 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-30 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-31 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Table 7-7 DATE: 3/21/2006 1 1 L.S. MOBILIZATION $ 5,180 $ 5,179.75 2 1 L.S. SPILL PREVENTION & COUNTER MEASURE PLAN $ 500 $ 500.00 3 1 L.S. TRAFFIC CONTROL $ 10,000 $ 10,000.00 4 1435 L.F. PAVEMENT TRENCH RESTO. ACP,9" ROCK) $ 30 $ 43,050.00 5 6 EA. CONNECT TO 48" STD STORM MANHOLE $ 500 $ 3,000.00 6 1435 L.F. TRENCH, EXCAVATION, & BACKFILL $ 12 $ 17,220.00 7 925 L.F. 18" STORM DRAIN PIPE $ 16 $ 14,800.00 8 490 L.F. 24" STORM DRAIN PIPE $ 22 $ 10,780.00 9 1415 L.F. IMPORTED PIPE BEDDING $ 2 $ 2,830.00 10 1415 L.F. TRENCH SAFETY SYSTEMS $ 1 $ 1,415.00 NOTE: SUBTOTAL 108,775 $ CONTINGENCY 30% 32,632 $ 3. Assumes Manholes are reusable. WSST - $ 4. Costs based on COK Miscellaneous Storm Drainage, Contract P0402-04. ENG/ ADMIN 20% 28,281 $ TOTAL 169,689 $ UNIT PRICE PROJECT DESCRIPTION: COLUMBIA DRIVE & N. HARTFORD ST. STORM LINE REPLACEMENT ENGINEER'S OPINION OF PROBABLE COST 2. Assumes a 6 FT. deep trench. COLUMBIA DRIVE & N. HARTFORD ST. STORM CONVEYANCE IMPROVEMENTS 1. Not a revenue producing project, no sales tax. TOTAL COST ITEM NO. ITEM DESCRIPTION QUANTITY UNIT ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-32 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Water Quality Improvements Water Quality Improvements Water Quality Improvements Water Quality Improvements The Capital Improvements Program for Water Quality is based on the assumption that the City is committed to continuing its preferred method of treatment as bio- infiltration or the use of Underground Injection Control wells (UIC). As described previously in this section, there are a number of defined areas across the City that have critical parameters associated with infiltration design. These areas require the use of pretreatment prior to discharging the storm runoff in the ground. Additionally, the City also has a secondary water supply source in the form of two Ranney Wells in Columbia Park that have a relatively large 10 year aquifer recharge zone defined across the center of the City. In order to meet the intent of the State of Washington’s proposed UIC regulation and the SWMM for Eastern Washington’s presumptive approach to bio-infiltration for storm runoff treatment, the areas where City-owned UICs are located in defined UIC pre-treatment areas or in the 10-year aquifer recharge zone need to be addressed in one of three methods:
Retrofit the drywells to meet design standards of the SWMM for Eastern Washington,
Remove the drywell if the storm system can handle the additional flow, or
Pipe runoff from the area to a suitable discharge (surface or existing City system). To better manage the UICs within the City, Exhibit 7-1 provides five general management areas for the City to consider while conducting upgrades to the UICs. These areas correspond to the predicted UIC Pre-Treatment Areas (Figure 7-7a) by generally delineating the large areas of commercial and industrial development, major arterials with high average daily trip generation (ADT), areas of poor treatment soils, and areas with high groundwater. Table 7-10 lists the number of public drywells from City records in each UIC Management Area. The remaining city drywells are located outside one of the five UIC management areas. The UIC Management Area with the greatest risk to a water supply source is the Aquifer Recharge Zone, especially where land uses would already require additional pre-treatment. Armed with limited resources, the City of Kennewick’s water quality Capital Improvement Program should focus projects on this UIC Management Area. In other UIC Management areas, the City should retrofit on an opportunity basis during other development, road, and utility rehabilitation projects. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-33 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Exhibit 7-1 UIC Management Areas Table 7 Table 7 Table 7 Table 7-10 10 10 10 Documented Public Drywells per UIC Management Area Documented Public Drywells per UIC Management Area Documented Public Drywells per UIC Management Area Documented Public Drywells per UIC Management Area # Name Name Name Name # of Drywells # of Drywells # of Drywells # of Drywells 1 Columbia Center Blvd. 284 2 Clearwater 109 3 Columbia Park 0 4 10yr Aquifer Recharge Zone 253 5 East Kennewick 112 Figure 7-11 focuses on seven specific projects to manage the UIC wells within the Aquifer Recharge Zone to the standards as proposed by the Department of Ecology and the subsurface infiltration design parameters outlined in the SWMM for Eastern Washington. The strategy of the CIP is to remove UIC wells where existing ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-34 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc storm infrastructure can convey the storm runoff to a more appropriate discharge location. Where existing infrastructure is not already connected to the drywells, the projects remove the UIC wells along arterials and areas of defined pretreatment and replace them with new conveyance lines. Finally, this report recommends retrofitting all other drywells in the Aquifer Recharge Area by modifying the catch basins directly connected to the UIC, creating a two-stage UIC. Project AQ1 Project AQ1 Project AQ1 Project AQ1 – Aquifer Recharge Zone Drywell Retrofit Aquifer Recharge Zone Drywell Retrofit Aquifer Recharge Zone Drywell Retrofit Aquifer Recharge Zone Drywell Retrofit This project includes all public UICs within the Aquifer Recharge Zone that are not located along arterials or in defined pretreatment areas. In Figure 7-11, the drywells depicted in yellow show the locations of the drywells targeted for retrofit with this project. The retrofit would pertain to the catch basins connected directly to the drywells by installing a turned down pipe elbow as shown in Figure 1, in Appendix H. A challenge in the retrofit is that installing a 12-inch pipe tee in a standard catch basin (24 inches by 24 inches) requires that the tee be set directly below the inlet grate collecting runoff. This eliminates the whole purpose for installing the tee and creates a future maintenance challenge. Therefore, the retrofits assume the removal of the existing catch basins and installation of standard 48-inch diameter manholes with inlet grates and 12-inch pipe tees. Table 7-11 outlines the estimated costs of installation. The project targets nearly 300 drywells, each with an average of 2.2 connecting catch basins for retrofit. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-35 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Table 7-11 DATE: 9/6/2005 1 1 L.S. MOBILIZATION $ 1,779 $ 1,778.70 2 1 L.S. TRAFFIC CONTROL $ 400 $ 400.00 3 200 C.Y. ROADWAY EXCAVATION INCL. HAUL $ 10 $ 2,000.00 4 100 C.Y. EMBANKMENT COMPACTION $ 4 $ 400.00 5 30 TON CRUSHED SURFACING BASE COURSE $ 11 $ 330.00 6 10 TON CRUSHED SURFACING TOP COURSE $ 12 $ 120.00 7 14 TON HMA CL B PG-64-28 $ 40 $ 560.00 8 10 EA. 48" STD STORM MANHOLE $ 1,800 $ 18,000.00 9 400 S.Y. SOIL RESIDUAL HERBICIDE $ 2 $ 800.00 10 400 L.F. SAWCUT EXISTING AC PAVEMENT $ 2 $ 800.00 11 100 L.F. 12" STORM $ 20 $ 2,000.00 NOTE: SUBTOTAL 27,189 $ CONTINGENCY 30% 8,157 $ WSST - $ TOTAL 35,345 $ 1. Catch basin retrofits have been costed out in groups of 10. PROJECT DESCRIPTION: Catch retrofit ENGINEER'S OPINION OF PROBABLE COST QUANTITY UNIT UNIT PRICE 10 Retrofit Catchbasins TOTAL COST ITEM NO. ITEM DESCRIPTION ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-36 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Project AQ2 Project AQ2 Project AQ2 Project AQ2 – W. C W. C W. C W. Columbia Dr. Drywell Removal olumbia Dr. Drywell Removal olumbia Dr. Drywell Removal olumbia Dr. Drywell Removal The drywells located in the W. Columbia Drive project area are defined as 2 stage pretreatment or pretreatment of oils and solids. Because this location is relatively close to the City’s Ranney wells and industrial/ commercial zoned, this report recommends the removal of the UIC wells through the installation of a new conveyance to discharge into the COE ditch. The project would remove 12 drywells and install approximately 4,300 LF of storm drainage pipe (3,250 LF of 12-inch diameter, 880 LF of 15-inch diameter, 170 LF of 18-inch diameter). This project should be implemented along with other street or utility improvements scheduled for the project area by the City. Project AQ3 Project AQ3 Project AQ3 Project AQ3 – W. Kennewick Ave. Drywell Removal W. Kennewick Ave. Drywell Removal W. Kennewick Ave. Drywell Removal W. Kennewick Ave. Drywell Removal The existing storm drainage system along W. Kennewick Ave. consists of a series of unconnected drywells. The arterial is heavily traveled by residents of the City and is well within the Aquifer Recharge Zone. The recommended solution removes the existing drywells and pipes the storm runoff to an existing City storm conveyance system at the intersection of N. Fruitland St. and W. Kennewick Ave. The ultimate discharge point for the drainage would be the COE ditch along the Columbia River Levee. The project removes six drywells and installs 2,800 LF of 12-inch diameter storm drainage pipe. This presents a decision for the City on how to handle flows. The immediate reach of piping in N. Fruitland St. is 10 inches in diameter for approximately 730 LF. The model predicts surcharging of this line in future conditions with the drywells removed along Kennewick Ave. However, there is no flooding or overtopping predicted in the existing conditions 25 year storm event. The piping of the 10-inch storm lines in Fruitland increases to 15-inch and then 21-inch diameter and appears to easily handle the flows. The City can elect to delay the upsizing of the storm line in N. Fruitland St. from W. Kennewick Ave. to W. Canal Dr. The proposed project and cost estimate does not reflect the upsizing of the storm line in N. Fruitland St. Project AQ4 Project AQ4 Project AQ4 Project AQ4 – S. Vancouver St. & W. 10 S. Vancouver St. & W. 10 S. Vancouver St. & W. 10 S. Vancouver St. & W. 10th th th th Ave. Drywell Removal Ave. Drywell Removal Ave. Drywell Removal Ave. Drywell Removal The storm drainage system along S. Vancouver St. contains a series of connected drywells that run south to north. The conveyance system breaks at W. 10th Ave. and conveys half of the storm runoff to S. Rainier Ave. The runoff eventually discharges into a 78-inch diameter conveyance line dedicated to run-off from Zintel Canyon. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-37 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc The recommended solution removes 21 existing drywells and connects approximately 780 LF of 12-inch diameter storm pipe to ensure the proper conveyance of the storm runoff. The future model has predicted sufficient capacity in the piping to convey the 25 year storm without the drywells in S. Vancouver St. Project AQ5 Project AQ5 Project AQ5 Project AQ5 – S. Ely St. & W. 10 S. Ely St. & W. 10 S. Ely St. & W. 10 S. Ely St. & W. 10th th th th Ave. Drywell Removal Ave. Drywell Removal Ave. Drywell Removal Ave. Drywell Removal The storm drainage system on S. Ely St. and its intersection with W. 10th Ave. contains a number of unconnected drywells. The project removes the drywells in the northern half of the project and connects the flow to the collection system in W. 10th Ave. The runoff would discharge into Zintel Canyon at the Zintel Bridge. A new outfall would need to be constructed to dissipate energy and prevent erosion. Runoff from drywells in the south half of the project would be connected to existing storm lines and discharge into Zintel Canyon near the Waste Management transfer station. The total project includes removing 34 existing drywells and constructing approximately 5,400 LF storm pipe. The required diameter of the storm piping would be dependent on design by the City. For instance, many of the adjacent existing streets are not designed to City standard with curb and gutter. The design of the conveyance piping would need to consider the adjacent parcels and their handling of storm water. For the cost estimate, the piping is assumed to construct 4,600 LF of 12-inch diameter and 800 LF of 15-inch diameter. Project AQ6 Project AQ6 Project AQ6 Project AQ6 – Vista Way Drywell Removal Vista Way Drywell Removal Vista Way Drywell Removal Vista Way Drywell Removal This project is a relatively small project to remove one existing drywell and connect the storm runoff into the storm system in W. Kennewick Ave. The existing drywell is located in the middle of a heavy traffic location surrounded by commercial retail area. The area is defined as a pretreatment area for oil. Rather than retrofit and maintain an oil pretreatment facility, the recommended project removes the use of the drywell and installs approximately 430 LF of storm drainage pipe. The storm runoff without pretreatment would connect to the storm drainage system in W. Kennewick Ave. and convey east to the golf course ponds. This solution does not provide designed treatment for the heavy traffic location, but it removes the direct infiltration of pollutant laden storm runoff into the 10 year aquifer recharge zone. Specific treatment alternatives for storm runoff in the W. Kennewick Ave. and Hwy 395 intersection needs to be addressed with a regional solution that most likely incorporates the benefits provided from the golf course ponds and Family Fishing Pond prior to discharge into the Columbia River. ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-38 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc Project AQ7 Project AQ7 Project AQ7 Project AQ7 – W. 27th Ave. & Hwy 395 Drywell Removal W. 27th Ave. & Hwy 395 Drywell Removal W. 27th Ave. & Hwy 395 Drywell Removal W. 27th Ave. & Hwy 395 Drywell Removal Drainage around the newly developed commercial retail area on W. 27th Ave. and Hwy 395 is served by a series of drywells and is defined as an oil pretreatment area for UIC wells. This area will most likely carry a heavy traffic component with development pressure in the commercial zoning. The adjacent intersection is planned to be a transportation corridor for the proposed South Ridge master plan area. The recommended project connects the existing drywells with a new conveyance pipe and requires a water quality treatment facility that would remove the oil and solids from storm runoff. The City would need to acquire a suitable amount of land for the facility. The facility would discharge the runoff into ground through infiltration after treatment. This project requires approximately 4,150 LF of storm pipe (diameter to be designed), the removal of 34 drywells, and the construction of a water quality treatment facility. Because this area is being developed very quickly, it is important for the City to act on the recommended solution quickly in order to secure the land for an adequate facility. Summary Summary Summary Summary The CIP presented in this section includes a total of ten projects; three projects to address existing and future system capacity deficiencies; six projects to address specific water quality concerns by removing drywells; and one long-term project to retrofit drywells within the aquifer recharge area. The total cost of all ten projects is $4.1 Million (2005 estimate). System capacity deficiencies were determined based on hydrologic and hydraulic modeling using HYDRA software. The water quality concerns come from the UIC treatment analysis presented in this section. This analysis provides a basis for forming a UIC Program to address the regulatory requirements for UIC compliance. Table 7-5 outlines a suggested implementation of the CIP program. Under that implementation, the City’s 5-year CIP cost is estimated to be $1.8 Million. With projects occurring over a number of years, the annual costs of the CIP to the Stormwater program are between $100,000 and $650,000 for the six years. Capacity related projects have been placed on the implementation schedule to occur every four years, however, the actual timing will depend on when other capital improvements are scheduled in the local area. Water quality projects are expected to be implemented over the next eight years. Ongoing UIC compliance activities to retrofit drywells in the aquifer recharge area may continue for at least the next 12 years. System capacity deficiency project costs include a 20% mark-up to cover engineering and administration costs associated with designing and implementing each project. However, because projects will likely be implemented over a long term ---PAGE BREAK--- Section 7 — Capital Improvement Program Development Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 7-39 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 7.doc schedule, it is assumed that existing staff can design the projects or manage a subconsultant doing the work. In addition, most water quality projects are assumed to be completed by maintenance crews with little design time required. Existing City staffing levels should be adequate to administer the CIP. No additional FTEs are needed. The projects presented in this section form the CIP program to address existing and future stormwater infrastructure needs in the City of Kennewick. This program, along with the regulatory compliance activities presented in Section 6, will require additional funding to develop a comprehensive surface water management plan. The future funding requirements and potential strategies for developing a funding base are presented in further detail in Section 8. ---PAGE BREAK--- Stormwater Model Columbia River FIGURE 7-1 Legend Nodes Pipe Ditch Gutter Overland Ditch Ditch Ditch Sub-Basins Lakes and Rivers Irrigation Canals
0 1,400 2,800 4,200 5,600 700 Feet ---PAGE BREAK---




































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































t u 240 US HWY 395 W 10TH AVE W CANAL DR S ELY ST W 27TH AVE W 4TH AVE W KENNEWICK AVE S OLYMPIA ST W 45TH AVE S UNION ST S GARFIELD ST W CLEARWATER AVE S MORAIN ST N YELM ST W COLUMBIA DR N NEEL ST W A ST N MORAIN ST N UNION ST VINEYARD DR S OLYMPIA ST Legend Drywells Remove Drywell Retrofit Ranny Wells STORM MAINLINE
STORM CATCHBASIN STORM MANHOLES IRRIGATION CANAL CIP_WQ RR Tracks 10yr Aquifer Recharge UIC Pretreatment No Pretreatment Req 2-Stage Pretreat Oil Pretreat Oil & Solids Pretreat Solids Columbia River Notes: 1. Wellhead Protection Zone is obtained from the 1997 City of Kennewick Wellhead Protection Plan by Golder Associates, Figure 22 Wellhead Protection Areas. The boundary corresponds to the 10 year condition.
0 660 1,320 1,980 2,640 330 Feet AQ2 - W. Columbia Dr. Drywell Removal AQ3 - W. Kennewick Ave. Drywell Removal AQ5 - S. Ely St. & W. 10th Ave. Drywell Removal AQ4 - S. Vancouver St. & W. 10th Ave. Drywell Removal AQ7 - W. 27th Ave. & Hwy 395 Drywell Removal AQ6 - Vista Way Drywell Removal AQ1 - Aquifer Recharge Zone Drywell Retrofit FIGURE 7-11 ---PAGE BREAK--- 523 521 19 23 505 31 522 7 8 4 3 61 1 36 35 6 581 33 41 919 22 177 5 21 2 502 460 682 501 81 13 9 917 451 12 175 774 166 14 503 176 178 455 34 18 75 92 583 74 820 32 37 853 426 561 854 629 508 537 377 578 895 392 894 20 780 606 155 232 196 78 915 275 667 652 625 638 63 543 582 204 646 504 149 457 538 711 90 714 79 25 88 376 393 62 167 718 42 170 48 665 712 468 156 533 163 94 661 863 680 379 51 198 93 823 916 95 716 50 639 191 580 636 649 188 571 577 529 918 705 263 168 942 506 449 222 674 568 824 896 688 127 364 17 456 559 182 526 91 125 858 84 601 760 903 39 609 210 913 724 399 193 262 628 719 950 713 403 378 727 202 172 416 812 659 602 16 943 637 415 656 879 735 26 199 590 631 704 862 218 411 706 607 556 27 89 536 189 728 87 544 450 206 251 938 179 658 859 383 30 666 914 385 396 225 117 563 201 40 864 213 679 630 38 683 214 933 422 937 860 494 509 186 386 267 816 535 429 10 677 98 908 897 224 866 209 861 49 813 146 603 405 208 240 397 375 55 527 400 553 159 394 404 86 419 190 467 181 710 865 565 567 832 183 890 207 150 481 147 622 811 372 447 169 11 932 573 454 119 305 612 345 417 158 551 531 197 278 406 562 398 370 530 663 906 212 605 185 694 134 423 220 428 611 459 867 260 351 825 745 101 898 779 77 686 486 558 857 97 414 721 24 80 703 120 818 128 452 121 944 560 15 99 129 759 911 684 83 539 427 438 632 807 238 242 446 171 151 369 82 817 935 219 413 374 623 483 541 970 136 64 102 418 431 216 352 409 187 621 641 363 410 624 870 575 549 194 655 430 934 880 245 116 421 784 153 653 173 570 192 746 675 633 955 105 85 626 341 137 124 588 702 130 518 96 764 852 76 300 708 253 309 110 875 579 271 707 432 593 139 640 152 871 528 723 673 627 122 507 635 821 437 790 448 72 654 806 643 951 157 301 804 564 608 803 408 246 118 762 697 109 53 600 744 184 791 662 362 576 569 589 829 391 195 239 304 283 650 412 796 693 365 555 435 514 597 909 819 709 532 548 259 615 835 492 936 57 598 160 223 123 887 902 281 869 490 307 594 592 164 244 113 778 445 797 237 525 424 828 496 928 945 254 787 433 52 948 318 822 162 720 660 940 540 104 767 690 180 830 546 927 443 336 969 498 834 381 729 226 389 425 782 519 205 66 145 700 584 174 111 265 856 380 473 54 359 749 140 810 228 371 217 106 361 344 634 513 845 241 557 805 596 493 783 231 517 520 395 904 848 346 488 390 453 315 850 115 868 642 328 135 103 200 233 143 788 651 70 676 566 809 799 910 302 534 510 926 877 613 750 282 472 73 487 689 133 946 243 786 808 516 100 885 836 299 891 401 701 308 303 444 840 439 681 284 599 695 114 407 358 108 587 297 657 664 691 614 952 574 338 165 907 56 337 726 252 276 485 591 272 547 126 924 717 65 841 742 939 754 144 138 234 339 331 884 347 420 324 340 294 838 550 524 258 738 402 107 132 280 436 961 610 669 739 141 792 67 542 956 293 618 266 814 699 69 967 953 327 876 929 930 912 847 330 554 329 499 921 644 770 287 968 645 794 512 731 382 964 356 489 366 755 734 250 696 737 388 793 306 773 348 572 350 595 648 855 888 229 925 475 373 647 920 752 962 497 827 29 384 882 844 154 268 477 620 269 736 963 831 586 878 332 826 873 893 484 949 730 286 221 112 367 270 227 515 323 326 434 317 511 923 958 462 354 28 342 753 47 333 440 815 296 320 273 901 295 314 285 671 289 291 678 604 290 343 872 236 131 881 692 851 748 142 743 552 763 464 751 670 619 60 775 478 71 461 469 795 960 668 957 766 274 58 491 545 732 264 148 203 698 230 886 959 685 941 46 495 161 277 965 883 465 798 756 360 44 672 833 900 319 322 470 725 785 733 687 802 892 441 849 235 288 387 905 43 334 715 482 249 68 761 954 45 500 947 313 771 777 837 368 889 617 765 747 247 800 966 931 355 874 616 59 463 789 471 311 839 842 740 442 776 801 758 211 585 312 279 466 353 255 741 843 781 476 310 335 768 899 325 215 772 722 458 248 474 298 349 357 846 261 257 480 922 256 479 82   240 US HWY 395 W 10TH AVE W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST E A ST W 4TH AVE S OAK ST S CLODFELTER RD W KENNEWICK AVE GAGE BLVD E CHEMICAL DR E BOWLES RD S OLYMPIA ST E 10TH AVE E 27TH AVE E LEWIS ST W 45TH AVE N KELLOGG ST N 14TH AVE STATE HWY 397 N 20TH AVE N 4TH AVE S UNION ST S GARFIELD ST N 1ST AVE N RD 36 S EDISON ST S 4TH AVE W AINSWORTH ST N YELM ST E FINLEY RD E AINSWORTH ST N RD 56 COLUMBIA PARK TRAIL S RD 28 S 1ST ST E AINSWORTH AVE N OREGON AVE KEENE RD S 20TH AVE RD 56 COLUMBIA CENTER BLVD S OLYMPIA ST Modeled Sub-Basins   395 City of Richland Columbia River FIGURE 7-2 City of Pasco   395 Legend Sub-Basins Lakes and Rivers Irrigation Canals RR Tracks City Bndy UGA Bndy
0 1,400 2,800 4,200 5,600 700 Feet ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST E A ST W 4TH AVE S CLODFELTER RD S OAK ST W KENNEWICK AVE GAGE BLVD E BOWLES RD E CHEMICAL DR S OLYMPIA ST E 10TH AVE E LEWIS ST E 27TH AVE W 45TH AVE N 14TH AVE N KELLOGG ST STATE HWY 397 N 4TH AVE N 20TH AVE N EDISON ST S UNION ST N RD 36 N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST E FINLEY RD S KELLOGG ST N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL S RD 28 W 1ST AVE S 1ST ST N NEEL ST E AINSWORTH AVE S WASHINGTON ST N OREGON AVE KEENE RD E BADGER RD N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST S COLUMBIA CENTER BLVD KENNEWICK AVE W QUINAULT AVE S 20TH AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S OLYMPIA ST Modeled Existing Imperviousness   395 City of Richland Columbia River FIGURE 7-3 City of Pasco   395 Legend RR Tracks City Bndy UGA Bndy Water Bodies Irrigation Canals Imperviousness 2% - 10% 10% - 20% 20% - 40% 40% - 60% 60% - 85%
0 1,500 3,000 4,500 6,000 750 Feet ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST E A ST W 4TH AVE S CLODFELTER RD S OAK ST W KENNEWICK AVE GAGE BLVD E BOWLES RD E CHEMICAL DR S OLYMPIA ST E 10TH AVE E LEWIS ST E 27TH AVE W 45TH AVE N 14TH AVE N KELLOGG ST STATE HWY 397 N 4TH AVE N 20TH AVE N EDISON ST S UNION ST N RD 36 N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST E FINLEY RD S KELLOGG ST N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL S RD 28 W 1ST AVE S 1ST ST N NEEL ST E AINSWORTH AVE S WASHINGTON ST N OREGON AVE KEENE RD E BADGER RD N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST S COLUMBIA CENTER BLVD KENNEWICK AVE W QUINAULT AVE S 20TH AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S OLYMPIA ST Modeled Future City Growth (20 Years)   395 City of Richland Columbia River FIGURE 7-4 City of Pasco   395 Legend RR Tracks City Bndy UGA Bndy Lakes and Rivers Irrigation Canals Increase % Impervious 0 - 5 5 - 15 15 - 30 30 - 52 52+
0 1,500 3,000 4,500 6,000 750 Feet ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST E A ST W 4TH AVE S OAK ST S CLODFELTER RD W KENNEWICK AVE GAGE BLVD E CHEMICAL DR E BOWLES RD S OLYMPIA ST E 10TH AVE E 27TH AVE E LEWIS ST W 45TH AVE N 14TH AVE N KELLOGG ST N 4TH AVE N 20TH AVE N EDISON ST STATE HWY 397 S UNION ST N RD 36 N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST E FINLEY RD FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST N OREGON AVE E AINSWORTH AVE N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST KEENE RD S COLUMBIA CENTER BLVD KENNEWICK AVE W QUINAULT AVE S 20TH AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S OLYMPIA ST 25-Year Storm Event Flooding (Existing)   240   395 City of Richland Columbia River FIGURE 7-6a Family Fishing Pond Frog Pond Duffy's Pond Columbia Cntr R/D Pond Mall R/D Facility City of Pasco E. 23rd R/D Facility Clearwater R/D Facility   395 Legend Flooding Nodes Links Sub-Basins RR Tracks City Bndy UGA Bndy Irrigation Canals Lakes and Rivers
0 1,400 2,800 4,200 5,600 700 Feet ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST E A ST W 4TH AVE S OAK ST S CLODFELTER RD W KENNEWICK AVE GAGE BLVD E CHEMICAL DR E BOWLES RD S OLYMPIA ST E 10TH AVE E 27TH AVE E LEWIS ST W 45TH AVE N KELLOGG ST N 14TH AVE N 4TH AVE N 20TH AVE N EDISON ST STATE HWY 397 S UNION ST N RD 36 N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST E FINLEY RD FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST N OREGON AVE E AINSWORTH AVE N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST KEENE RD S COLUMBIA CENTER BLVD KENNEWICK AVE W QUINAULT AVE S 20TH AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S OLYMPIA ST 25-Year Storm Event Flooding (Future)   240   395 City of Richland Columbia River FIGURE 7-6b Family Fishing Pond Frog Pond Duffy's Pond Columbia Cntr R/D Pond Mall R/D Facility City of Pasco E. 23rd R/D Facility Clearwater R/D Facility   395 Legend Flooding Nodes Links Sub-Basins RR Tracks Irrigation Canals City Bndy UGA Bndy Lakes and Rivers
0 1,400 2,800 4,200 5,600 700 Feet ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR LESLIE RD W A ST W CLEARWATER AVE W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST E A ST W 4TH AVE S OAK ST S CLODFELTER RD W KENNEWICK AVE GAGE BLVD E CHEMICAL DR E BOWLES RD S OLYMPIA ST E 10TH AVE E 27TH AVE E LEWIS ST W 45TH AVE N 14TH AVE N KELLOGG ST N 4TH AVE N 20TH AVE N EDISON ST STATE HWY 397 S UNION ST N RD 36 N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST E FINLEY RD FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST N OREGON AVE E AINSWORTH AVE N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST KEENE RD S COLUMBIA CENTER BLVD KENNEWICK AVE W QUINAULT AVE S 20TH AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S OLYMPIA ST Proposed Stormwater CIP Projects   395 City of Richland Columbia River FIGURE 7-6c City of Pasco   395 Legend CIP Flooding Nodes Links Sub-Basins RR Tracks City Bndy UGA Bndy Irrigation Canals Lakes and Rivers
0 1,400 2,800 4,200 5,600 700 Feet C1 C3 C4 C2 Planned for Construction Managed with Future Commercial Development Maintain and Observe Maintain and Observe ---PAGE BREAK--- 82   240 US HWY 395 W 10TH AVE W CANAL DR W 27TH AVE W A ST S ELY ST W 4TH AVE W CLEARWATER AVE W KENNEWICK AVE S OLYMPIA ST W LEWIS ST E 10TH AVE E 27TH AVE N KELLOGG ST N EDISON ST S UNION ST S GARFIELD ST W COLUMBIA DR S EDISON ST S MORAIN ST N GUM ST S KELLOGG ST N YELM ST E 1ST AVE FAIRWAY ST W AINSWORTH ST W 1ST AVE N NEEL ST E CHEMICAL DR S WASHINGTON ST N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST S COLUMBIA CENTER BLVD S RD 28 KENNEWICK AVE N UNION ST S 20TH AVE S 10TH AVE VINEYARD DR BN FR INTER COUNTY BRIDGE N WASHINGTON ST N COLUMBIA CENTER BLVD S OLYMPIA ST Future Gutter Flow Concerns 25-Year Storm Event   240   395 Columbia River FIGURE 7-6d   395
0 920 1,840 2,760 3,680 460 Feet Legend Over Capacity Gutter Nodes Links RR Tracks Irrigation Canals Lakes and Rivers ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR W COURT ST LESLIE RD W A ST E A ST W CLEARWATER AVE W 27TH AVE S ELY ST S HANEY RD W LEWIS ST W SYLVESTER ST W 4TH AVE S OAK ST S CLODFELTER RD E BOWLES RD W KENNEWICK AVE GAGE BLVD E LEWIS ST STATE HWY 397 E CHEMICAL DR S OLYMPIA ST E 10TH AVE N 14TH AVE E FINLEY RD E 27TH AVE W 45TH AVE N 4TH AVE N KELLOGG ST N 20TH AVE N RD 36 N EDISON ST E AINSWORTH AVE S UNION ST N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL N OREGON AVE S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST KEENE RD N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST S COLUMBIA CENTER BLVD KENNEWICK AVE W QUINAULT AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S KEYSTONE ST S OLYMPIA ST Legend Storm Drywells Aquifer Recharge Lakes_Rivers RR Tracks City_Bndy UGA_Bndy UIC Pretreatment No Pretreatment Req 2-Stage Pretreat Oil Pretreat Oil & Solids Pretreat Solids
0 1,600 3,200 4,800 6,400 800 Feet FIGURE 7-7a 2. This figure has been completed using generalized water table and subsurface soil information in order to provide the City of Kennewick a planning tool to predict UIC pretreatment requirements. Proposed UIC facilities should verify the site conditions with the guidance provided in the Stormwater Mangement Manual for Eastern Washington and the Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State to make their own determination for suitable pretreatment. Notes: 1. UIC Pretreatment requirements have been derived from Table 3 of the Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State, Revised Draft, April 22, 2005. Table 3 uses a presumptive approach by combining pollutant loading and treatment capacity of subsurface soils to prescribe pretreatment for UICs. Figures 7-7b through 7-7e provide the data used to determine pretreatment requirements. UIC PRETREATMENT REQUIREMENTS Frog Pond Frog Pond ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR W COURT ST LESLIE RD W A ST E A ST W CLEARWATER AVE W 27TH AVE S ELY ST S HANEY RD W LEWIS ST W SYLVESTER ST W 4TH AVE S OAK ST S CLODFELTER RD E BOWLES RD W KENNEWICK AVE GAGE BLVD E LEWIS ST STATE HWY 397 E CHEMICAL DR S OLYMPIA ST E 10TH AVE N 14TH AVE E FINLEY RD E 27TH AVE W 45TH AVE N 4TH AVE N KELLOGG ST N 20TH AVE N RD 36 N EDISON ST E AINSWORTH AVE S UNION ST N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL N OREGON AVE S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST KEENE RD N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST S COLUMBIA CENTER BLVD KENNEWICK AVE W QUINAULT AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S KEYSTONE ST S OLYMPIA ST Legend Storm Drywells Lakes_Rivers RR Tracks City_Bndy UGA_Bndy Pollutant load High Medium Low
0 1,600 3,200 4,800 6,400 800 Feet FIGURE 7-7b POLLUTANT LOADING CLASSIFICATIONS FOR UICs ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR W COURT ST LESLIE RD W A ST E A ST W CLEARWATER AVE W 27TH AVE S ELY ST S HANEY RD W LEWIS ST W SYLVESTER ST W 4TH AVE S OAK ST S CLODFELTER RD E BOWLES RD W KENNEWICK AVE GAGE BLVD E LEWIS ST STATE HWY 397 E CHEMICAL DR S OLYMPIA ST E 10TH AVE N 14TH AVE E FINLEY RD E 27TH AVE W 45TH AVE N 4TH AVE N KELLOGG ST N 20TH AVE N RD 36 N EDISON ST E AINSWORTH AVE S UNION ST N 1ST AVE S GARFIELD ST W COLUMBIA DR S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL N OREGON AVE S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST KEENE RD N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST S COLUMBIA CENTER BLVD KENNEWICK AVE W QUINAULT AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S KEYSTONE ST S OLYMPIA ST Legend Storm Drywells Lakes_Rivers RR Tracks City_Bndy UGA_Bndy Infiltration Rate (in/hr) 17.500 - 20+ 15.500 - 17.5 13.500 - 15.5 10.000 - 13.5 6.500 - 10 4.500 - 6.5 2.500 - 4.5 1.000 - 2.5 0 - 1
0 1,600 3,200 4,800 6,400 800 Feet PREDICTED SOIL INFILTRATION RATES Notes: 1. Soil characteristics and infiltration estimates were obtained from the SCS, July 1971, Soil Survey for Benton County Area. 2. The predicted soil infiltration rate figure is directed towards describing appropriate areas within the City for drywell construction. When applicable to a specific soils type, infiltration estimates shown may differ for surface conditions because they were taken from lower horizons to approximate infiltration for constructed drywells. 3. Predicted soil infiltration rates are provided for planning purposes only. Actual infiltration rates should be obtained through on-site analysis. FIGURE 7-7c ---PAGE BREAK--- 80 60 55 50 45 85 40 65 70 75 35 30 25 20 15 90 95 5 10 100 105 110 125 120 115 130 50 100 80 75 105 40 30 80 45 95 85 85 60 85 15 70 20 30 65 70 80 35 30 40 25 80 60 60 60 35 55 85 90 65 15 10 60 50 80 10 5 25 30 45 45 40 70 50 45 30 65 35 80 45 30 100 10 75 105 35 20 5 55 50 25 90 40 85 5 95 5 5 25 50 50 65 20 40 65 90 60 55 45 40 70 15 45 35 85 25 5 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR W COURT ST LESLIE RD W A ST W CLEARWATER AVE E A ST W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST W 4TH AVE S OAK ST S CLODFELTER RD W KENNEWICK AVE E BOWLES RD GAGE BLVD E LEWIS ST E CHEMICAL DR STATE HWY 397 S OLYMPIA ST E 10TH AVE N 14TH AVE E 27TH AVE E FINLEY RD W 45TH AVE N 4TH AVE N KELLOGG ST N 20TH AVE N RD 36 N EDISON ST S UNION ST N 1ST AVE S GARFIELD ST W COLUMBIA DR E AINSWORTH AVE S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL N OREGON AVE S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST N COLUMBIA CENTER BLVD KENNEWICK AVE KEENE RD N UNION ST S 20TH AVE RD 56 VINEYARD DR BN FR INTER COUNTY BRIDGE S OLYMPIA ST Legend Storm Drywells Groundwater Contr RR Tracks Lakes & Rivers City Bndy UGA Bndy Groundwater Depth (ft) < 6 6 - 10 10 - 25 > 25
0 1,500 3,000 4,500 6,000 750 Feet Note: Groundwater depths are obtained from 1997 City of Kennewick Wellhead Protection Plan by Golder Associates, Figure 21 Calibrated Water Table Elevation. The contours shown are planning level estimates and should be confirmed through field investigation. FIGURE 7-7d AVERAGE DEPTH TO SEASONAL GROUNDWATER  Frog Pond   395 City of Richland City of Pasco   395 ---PAGE BREAK--- 82   240 US HWY 395 COLUMBIA PARK TRAIL W 10TH AVE W CANAL DR W COURT ST LESLIE RD W A ST W CLEARWATER AVE E A ST W 27TH AVE S ELY ST W LEWIS ST W SYLVESTER ST W 4TH AVE S OAK ST S CLODFELTER RD W KENNEWICK AVE E BOWLES RD GAGE BLVD E LEWIS ST E CHEMICAL DR STATE HWY 397 S OLYMPIA ST E 10TH AVE N 14TH AVE E 27TH AVE E FINLEY RD W 45TH AVE N 4TH AVE N KELLOGG ST N 20TH AVE N RD 36 N EDISON ST S UNION ST N 1ST AVE S GARFIELD ST W COLUMBIA DR E AINSWORTH AVE S EDISON ST S 4TH AVE S MORAIN ST W AINSWORTH ST N GUM ST S KELLOGG ST N YELM ST FAIRWAY ST E AINSWORTH ST E 1ST AVE N RD 56 COLUMBIA PARK TRAIL N OREGON AVE S RD 28 W 1ST AVE S 1ST ST N NEEL ST S WASHINGTON ST N COLUMBIA CENTER BLVD E COLUMBIA DR N MORAIN ST S COLUMBIA CENTER BLVD KENNEWICK AVE W QUINAULT AVE KEENE RD S 20TH AVE RD 56 COLUMBIA CENTER BLVD VINEYARD DR BN FR INTER COUNTY BRIDGE S OLYMPIA ST Legend City Bndy UGA Bndy Storm Drywells RR Tracks Lakes & Rivers Treatment Capacity High Medium Low None
0 1,500 3,000 4,500 6,000 750 Feet FIGURE 7-7e PRESUMED TREATMENT CAPACITY  Frog Pond   395 City of Richland City of Pasco   395 Notes: 1. Treatment capacity is a function of vadose zone layer characteristics of the soil and depth to groundwater as per Table 1 of the Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State, Revised Draft, April 22, 2005. 2. Soil characteristics and infiltration estimates were obtained from the SCS, July 1971, Soil Survey for Benton County Area. 3. Depth to groundwater estimates are shown in Figure 7-7d. Areas outside of the analyzed zone in Figure 7-7d were trended from adjacent areas, contours, and reliance on the SCS Soil Survey. 4. Presumed soil treatment capacities are provided for planning purposes. Actual treatment capacity can be obtained through on-site analysis of soil boring logs, soil analysis, and evidence of seasonal groundwater table. ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-1 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc The following financial plan supports the development and implementation of a comprehensive stormwater management program for the City of Kennewick. The funding plan covers each element of the City’s Comprehensive Stormwater Management Plan, including the forthcoming regulatory compliance requirements, capital project needs, and operation and maintenance of existing stormwater management functions. Funding alternatives have been developed to illustrate various ways that the program can be financed and implemented. Approximate stormwater utility rates have been estimated to help the City evaluate whether or not forming a utility should be undertaken. It is important for the City to review the adequacy of its stormwater funding sources soon, as NPDES II stormwater compliance requirements will likely begin by the end of 2006. The Financial Plan developed by Otak for the City’s proposed Comprehensive Stormwater Management Program consists of the following elements: • Revenue Needs • Current Funding Mechanisms • Financial Alternatives and Potential Funding Mechanisms • Recommended Funding Mechanisms • Recommended Financial Plan with Preliminary Utility Rates This section also includes a brief comparison of the estimated utility rates to the fees in other local communities. Revenue Needs Revenue Needs Revenue Needs Revenue Needs The approach was to first define the programmatic and capital needs of the City’s Stormwater Management Program. Once defined, an annualized implementation plan was prepared to meet the terms and conditions of the NPDES II Permit and the UIC Rule. Costs for each year were estimated and correlated with existing and future funding needs over the five year life of the City’s new NPDES II Permit. The primary planning goal was to estimate program and funding needs to support a fully implemented and enhanced Stormwater Management Program – a program that meets all regulatory requirements, addresses capital needs, and continues to fund annual local stormwater related activities and services to the community. The annual revenue needs for the City’s fully implemented, enhanced Surface Water Program (at the end of the first five-year NPDES Permit Period) are $1.41 M, as shown below. ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-2 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc • For Operations (revised existing program of $350K, plus new costs of about $700K): $1,050,000 • For Capital Improvements (Approximate 5-year average annual cost): $360,000 Annual total: $1,410,000 This estimate assumes that the City takes a “pay as you go” approach to CIPs rather than funding them over a longer term, or using other capital funding mechanisms such as bonding. The pay as you go approach requires the City to begin raising about $360K in annual CIP funding starting in 2007 and continuing through 2011. The annual operational costs, estimated at $1050K in 2011, can begin at a lower level in 2007 and then slowly increase as programs are put into place to comply with NPDES required activities and schedules. Current Funding Mechanisms Current Funding Mechanisms Current Funding Mechanisms Current Funding Mechanisms The City of Kennewick routinely uses various revenue sources and funding mechanisms to operate its existing SWM program, which consists of constructing capital improvement projects on an as needed basis, and conducting annual maintenance. The primary source of funding is the existing City-wide 0.5% sales tax, which has historically generated $400-450K per year for the City’s existing stormwater needs, primarily maintenance. To date, the sales tax has adequately served the City’s Stormwater Management Program and still remains a viable funding source to help address the City’s new regulatory compliance and capital needs. However, future stormwater program funding is scheduled to be reduced to approximately 350K per year due to budgeting within the City; the recommended financial plan and preliminary utility rates presented below will reflect the planned reduction in funding. In addition, to continue as the primary Stormwater revenue source, the annual sales tax withdrawal would need to triple its current annual allocation, as new regulatory compliance programs and related capital projects are required. Given the tight fiscal state of most municipal agencies, this option is not likely feasible. Instead, new levels and possibly new sources of annual funding will likely be required. Financial Alternatives Financial Alternatives Financial Alternatives Financial Alternatives and Funding Mechanisms and Funding Mechanisms and Funding Mechanisms and Funding Mechanisms To create the enhanced level of surface water revenue needed to support the City’s SWM program, several funding mechanisms have been considered ranging from forming a stormwater utility to establishing long-term inter-local cost sharing agreements. ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-3 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc For most municipal agencies, the multitude of stormwater activities, ranging from maintenance, to inspection/enforcement and capital construction, usually require a diversity of both short- and long-term revenue sources. Common revenue sources used by many municipal agencies to create adequate primary levels of annual funding for stormwater programs include: • Stormwater Utilities • Development Service/Permit Fees Other funding mechanisms that the City of Kennewick should consider in the future include: • Grants • Loans • Revenue Bonds • Fee in Lieu of Onsite Detention • Special Purpose Districts • General Facility Charges (GFCs) or System Development Charges (SDCs), and • Future Coordination with Other Agencies Each of the funding mechanisms is briefly described below. Surface Water Utility Surface Water Utility Surface Water Utility Surface Water Utility There are currently many Washington counties and cities that have developed and implemented surface water utilities as their primary source of funding to address the annual financial needs of their surface water programs (along with development permitting, plan review, and inspection fees). Establishing surface water utility charges is the most reliable means of financing SWM programs, particularly as additional water quality and regulatory compliance costs arise. This approach recognizes that the operation of stormwater drainage infrastructure, including related regulatory compliance efforts, is an essential public service, and, like water and sewer, needs to be paid for by those who are being served. Within a stormwater utility service area, it is possible to define various sub-service areas where rates and charges are set at different levels depending on who benefits from local or regional capital projects and the different costs of system operation and maintenance. Most municipal agencies eventually choose the formation of a Stormwater utility because the amount of revenue available from these other sources of funding, (i.e. fees, general facility charges, or general fund), is so limited, and rarely enough to support all the needs of a viable stormwater management program. Should the City, however, decide to continue the $350,000 annual allocation from the general fund, the needs from other revenue sources would be substantially smaller. As a result, if a Stormwater utility were proposed, its rates could be proportionally lower. ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-4 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc Development Development Development Development Service/Permit Fees Service/Permit Fees Service/Permit Fees Service/Permit Fees A City's fee-related services, including development permit review and construction and maintenance inspections should be 100 percent fee supported, if at all possible. It is usually in the City’s best long-term interest to not subsidize these types of services from the City's general fund or other sources of internal funding, including the agency’s stormwater utility revenues. Other Funding Other Funding Other Funding Other Funding and Financing and Financing and Financing and Financing Mechanisms Mechanisms Mechanisms Mechanisms to Consider When/If Appropriate to Consider When/If Appropriate to Consider When/If Appropriate to Consider When/If Appropriate Some of the more mature utility-based SWM programs have adequate annual revenues and fiscal standing to take advantage of long term capital project financing options, including bonding for capital needs, loans for special projects, and partnering for cost sharing with other agencies and/or developers. Occasionally, opportunities arise that allow an agency to take advantage of additional outside funding sources including; grants and establishing project specific Local Improvement Districts (LIDs). These revenue sources, once established, augment annual SWM revenues, but would be inadequate as a primary source of funding for an entire SWM program. Other funding mechanisms that the City of Kennewick should consider in the future are: Grants Although increasingly competitive, this state still operates two grant programs that are available to the City including the State Centennial Clean Water Fund (CCWF) and Flood Control Assistance Account Program (FCAAP). These grants can be a good source of planning and habitat or water quality project funding. Awards can range up to $300K per project, with adequate project justification. In addition, Kennewick should continue to track new and emerging grant opportunities for stormwater work and seek grants when possible. The Department of Ecology may soon make grant funds available for NPDES program start-up activities, public education and involvement, monitoring and research, and on the ground stormwater quality projects. Loans The State's Public Works Trust Fund, State Revolving Fund (SRF) loans, as well as the CCWF and FCAAP, each contain loan programs for drainage and flood control related projects. Interest rates are usually low (1 to Loans may be a good funding source for projects once stable sources of annual revenues are established. The City has effectively used this type of funding to sponsor this current stormwater master planning project and estimate regulatory compliance and capital needs, as well as review opportunities for developing new funding sources. ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-5 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc Revenue Bonds Typically, bonding is difficult for a new stormwater program until a healthy fiscal standing has been attained. It would be especially difficult for the City of Kennewick at the present time since the program has a limited source of annual funding which is not strictly dedicated to the program over the long term. Bonding is also normally limited to capital projects that have already been designed and permitted. However, bonds can be a very useful funding mechanism for capital projects if the utility rates are enacted and are high enough to establish financial stability in the surface water utility. Financing options utilizing bonding can contribute a substantial amount to the annual needs of a SWM program. These types of revenue sources can address much of the capital project costs, depending on the annual utility rates, the financial stability of the surface water utility, and the financial rating and bonding capacity of the municipal agency. Their use helps to prevent fluctuating charges that may be necessary when using a pay-as-you go approach is used for CIP needs. However, it is important for a utility to have a reasonable operating reserve fund in order to demonstrate solvency and obtain an adequate bond rating. Annual utility rates must be high enough to allow revenue bonds to be issued for capital projects. There is always an annual payment to service the bond debt, which is usually about 10% of the bonded amount. Fee In Lieu of Onsite Detention One possible option for the City to consider is the establishment of a stormwater facility funding program where the developer pays a fee to the City. The City, in turn, accepts and retains peak flows in one or more regional retention/detention facilities or water quality treatment facilities. The amount of the fee would generally be equal to the projected cost of the developer to provide onsite detention and/or treatment. This option is usually used by jurisdictions that want to provide and operate regional facilities to accommodate detention and/or treatment needs of new development. Municipalities can make an area more attractive to new development while ensuring a high level of stormwater management and resource protection as that development occurs. The jurisdiction usually “fronts” the funds necessary to construct the facility in advance of the development then charges new development the “in-lieu of fee” to pay back the costs. This approach must be carefully planned out to ensure that the City has a high certainty of eventually being paid back. ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-6 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc Special Purpose Districts Special purpose districts can be an equitable approach to generate adequate levels of revenue for local and regional projects. The major advantages of this funding mechanism are that: • They can be set up to cross jurisdictional boundaries in order to follow basin and/or watershed boundaries, • They foster partnering with landowners and future developers and/or other agencies, • They are equitable, and • They have many of the same authorities for land acquisition, condemnation, ROW and fund raising that cities or counties have. The formation of some districts requires a majority vote of the existing property owners, and as such is often difficult to get initially established. In addition, some special districts are controlled by a private board of supervisors and operate outside the control of a city. General Facility Charges (GFCs) or System Development Charges (SDCs) GFCs/SDCs are paid by new developments to reimburse the local government for the cost of constructing additional capacity to drainage facilities. SDCs are often based on impervious area (a measure of runoff amount and impact on the drainage system). The amount of revenue raised by GFCs/SDCs is dependent on the amount and type of development that occurs within the City on an annual basis. This revenue source can vary from year to year depending on the local economy and building opportunities. While not recommended at this time for Kennewick, this option should be kept in mind for basins where significant development can still occur and where public infrastructure will be needed to accommodate that growth. Future Coordination Opportunities with Other Agencies The City of Kennewick should look for opportunities to collaborate with neighboring jurisdictions and agencies (like WSDOT) on stormwater work in order to: promote efficiency and save money; obtain fair solutions to problems that cross political boundaries; and promote consistency of standards and practices throughout the region. The City should look into coordination opportunities presented by conservation districts, irrigation and drainage districts, state and federal agencies, and other local governments. Agencies, such as WSDOT, the Cities of Pasco, Richland, and West Richland should be contacted about coordination possibilities. ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-7 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc Recommended Funding Mechanisms Recommended Funding Mechanisms Recommended Funding Mechanisms Recommended Funding Mechanisms Based on the above review and analysis of various financial alternatives and revenue generating mechanisms, the following sources of new revenue are recommended for near term implementation by the City: • Enacting a Surface Water Utility Program with fees, • Consider continuation of some level of the funding from the 0.5% sales tax, and • Reviewing and updating service/permit fees (development review and inspection fees). The two primary sources of funding are the formation of a dedicated Stormwater Utility and the continued use of a portion of the 0.5% sales tax for stormwater related activities. If the annual sales tax allocation is continued, the rates of a proposed Stormwater utility would be proportionately lower. However, if the City chooses, the formation of a stormwater utility is capable of providing almost all of the needed revenue, as discussed in greater detail below. This would allow the sales tax funds to be annually allocated to other City programs and priorities. The preceding review of the City’s program, capital, and regulatory compliance needs suggests that the City will need approximately $1.41M per year. This is an increase of about $1,060K per year over current levels of stormwater funding. To achieve this annual level of funding, the sales tax allocations should be retained at $350K per year. The remaining funds ($1,060K) would be provided by a new stormwater utility. The funds from the stormwater utility would be used to achieve regulatory compliance ($700K) and to fund capital projects ($360K). The City should also review and update its system of service fees, including permit and inspection fees, and review opportunities to enhance the use of system development charges to help the City develop the infrastructure needed to support new development. This approach recognizes that the operation of stormwater drainage infrastructure, including related regulatory compliance efforts, is an essential public service, and, like water and sewer, needs to be paid for by those who are being served. And just like water and sewer utilities, operating a stormwater management program is a business and needs to be funded and operated like a business, just like other utilities. ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-8 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc Recommended Financial Plan ecommended Financial Plan ecommended Financial Plan ecommended Financial Plan & Preliminary Preliminary Preliminary Preliminary Utility Rates Utility Rates Utility Rates Utility Rates Introduction Introduction Introduction Introduction The objective of developing a financial plan is to ensure that the operating and capital needs, as developed within the City’s Surface Water Management Plan, can be met with surface water utility rates that are reasonable and affordable. In order to determine approximate stormwater utility rates, it is necessary to have a reasonable estimate of: • Annual stormwater revenue requirements – how much will be spent in each year of the planning term on capital projects costs (debt service or pay-as-you go), operation and maintenance, regulatory compliance, reserve fund build-up, and miscellaneous external services (legal support, accounting, etc.); • Dependable non-utility annual stormwater revenue sources – how much money will be provided each year through mechanisms such as sales taxes, general tax funds, street funds, wastewater funds, permit fees, and other established sources; • Stormwater Utility Customer Account Information - how many customers of different types exist, what will the billing unit be (Equivalent Residential Unit), how many billing units are created, what policies are to be used (rate structures, credits, waivers, exemptions). Once these items are estimated, it is fairly straight forward to estimate annual stormwater rates, as well as the charge for a given property. For this plan, we will use a series of assumptions to provide an order of magnitude estimates for several financing alternatives. If the City chooses to pursue a stormwater utility (the development of which usually takes about a year itself) it will be necessary to perform additional work and complete a comprehensive rate study. From that review, a final financial plan would be developed that provides recommendations on surface water rates, and accounts for things like inflation and the effects of ongoing growth (increases in program costs and increases in revenues). Development of the Financial Plan Development of the Financial Plan Development of the Financial Plan Development of the Financial Plan The first step undertaken in this process was the review of the City’s revenue requirements. In this process, the projected period of CY 2007 – CY 2011 was reviewed (the first five-year NPDES Permit Term). CIP estimates extend beyond this period, so the CIP revenue estimate for year 1-5 is based on the average annual cost for projects needed in the first 5 years ($360K per year). The City must also incur additional expenditures over the next five plus years to meet the regulatory compliance requirements associated with NPDES II Municipal Stormwater Permit ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-9 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc and the Underground Injection Control Rule. The incremental programmatic and equipment expenses associated with meeting regulatory compliance are approximately $700,000 when fully phased-in by the end of 2010. In projecting the City’s costs, the existing stormwater revenues were decreased from their historic level of $450K to $350K to reflect a scheduled reduction in the general fund allocation, as discussed previously. Rough annual cost estimates will be prepared using the following process and assumptions: • Annual CIP costs (CIP IP IP IP) have been estimated to be equal to the average annual cost for projects needed in the first 5 years. This is a “pay-as-you-go” approach. • The dependable existing annual stormwater revenue (Rex ex ex ex) will be estimated based on information provided by City staff. • The maximum new annual stormwater program revenue required (Rmax max max max) will be estimated based upon the gap analysis (neglecting CIPs). The revenue needed each year (Rnew new new new) ) ) ) will be estimated by assuming that the program is incremented 20% each year. • The fully implemented annual program cost (year 5 costs) (Cfull full full full) will be estimated by adding the regulatory Gap Analysis costs to the existing program costs which is the same as dependable annual stormwater revenue estimate (still neglecting CIPs)). • It will be assumed that a program reserve fund equal to about 50% of the maximum new annual stormwater program revenue will be accumulated in the first 3 years at 1/3 per year (Rre re re res). • No interest or inflation will be included. • No “contingency factor” will be included. The following list of data has been developed from information provided in Sections 5, 6, and 7: • CIP CIP CIP CIP = $360,000/yr for 5 yrs (From Section 7) • Rex ex ex ex = $350,000 (From Section 5, including $100K budget reduction) • Rmax max max max = $700,000 in 2010 (From Gap Analysis & Section 6, including additional $100K of new required revenue resulting from budget reduction) • Rnew new new new = Rmax max max max/5 years = increase of $140K per year • Cfull full full full = Rex ex ex ex + R R R Rmax max max max = $1,050,000 in 2010 (estimate of fully implemented program costs, neglecting CIPs) • Rre re re res = 0.5(Rmax max max max)/3 = $100,000/yr for yrs 1-3 (approx. based on a total reserve fund of $300,000) From this information Table 8-1 has been prepared. The information will be used to develop an estimate of stormwater utility fees. ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-10 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc Table 8 Table 8 Table 8 Table 8-1 Estimated Annual Program Estimated Annual Program Estimated Annual Program Estimated Annual Program Costs and Required Revenues Costs and Required Revenues Costs and Required Revenues Costs and Required Revenues 2007 2007 2007 2007 2008 2008 2008 2008 2009 2009 2009 2009 2010 2010 2010 2010 2011 2011 2011 2011 5 Yr Tot. 5 Yr Tot. 5 Yr Tot. 5 Yr Tot. Existing Program Costs Rex ex ex ex $350,000 $350,000 $350,000 $350,000 $350,000 $1,750,000 $1,750,000 $1,750,000 $1,750,000 New Program Costs Rnew new new new $219,958 $339,916 $459,874 $579,832 $699,790 $2,299,370 $2,299,370 $2,299,370 $2,299,370 Total Progr Total Progr Total Progr Total Program am am am Cost Cost Cost Cost Cfull full full full $569,958 $569,958 $569,958 $569,958 $689,916 $689,916 $689,916 $689,916 $809,874 $809,874 $809,874 $809,874 $929,832 $929,832 $929,832 $929,832 $1,049,790 $1,049,790 $1,049,790 $1,049,790 $4,049,370 $4,049,370 $4,049,370 $4,049,370 CIP Costs CIP CIP CIP CIP $360,000 $360,000 $360,000 $360,000 $360,000 $1,800,000 $1,800,000 $1,800,000 $1,800,000 Reserve Fund Build-Up Rre re re res $100,000 $100,000 $100,000 $0 $0 $300,000 $300,000 $300,000 $300,000 Total Total Total Total Stormwater Stormwater Stormwater Stormwater Costs Costs Costs Costs $1,029,958 $1,029,958 $1,029,958 $1,029,958 $1,149,916 $1,149,916 $1,149,916 $1,149,916 $1,269,874 $1,269,874 $1,269,874 $1,269,874 $1,289,832 $1,289,832 $1,289,832 $1,289,832 $1,409,790 $1,409,790 $1,409,790 $1,409,790 $6,149,370 $6,149,370 $6,149,370 $6,149,370 Existing Revenues Rex ex ex ex $350,000 $350,000 $350,000 $350,000 $350,000 $1,750,000 $1,750,000 $1,750,000 $1,750,000 Req’d New Req’d New Req’d New Req’d New Revenue Revenue Revenue Revenue $679,958 $799,916 $919,874 $939,832 $1,059,790 $4,399,370 Req’d New Req’d New Req’d New Req’d New Rev Rev Rev Rev. minus . minus . minus . minus CIP CIP CIP CIP $319,958 $439,916 $559,874 $579,832 $699,790 $2,599,370 Utility Policies Utility Policies Utility Policies Utility Policies Before making an estimate of stormwater utility fees, it is necessary to discuss some of the background issues and decisions that typically surround stormwater utilities. These decisions must be addressed in the process of implementing the utility. • Determine Utility Policies and Rate Structure – The City Council should be consulted concerning how they want to set utility policies that govern the rate structure. Utility policies relate to considerations like: are non-profits, disabled, and low income property owners charged at the same rate as others?; should property owners who utilize on-site retention be given a credit towards their fee?; should fees be based only on impervious surface or should land use also affect rates?; should the rate structure differentiate between water quality and water quantity related costs?; should city streets be waived or charged at the same rate as other property owners?; should state highways be waived?; should owners of larger homes (with larger impervious surface ) pay more than owners of a small home?; etc. Remember, the more discounts, credits and waivers given out, the higher the rates will be for those remaining to pay. Also, the more the rate structure attempts to account for the many possible variables, the more complex it will be and the more time consuming it will be to administer. Policies are codified in the ordinance that establishes the utility. ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-11 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc • Determine the Billing Unit – Normally the billing unit is called an “Equivalent Residential Unit” (ERU) and is set about equal to the average amount of impervious surface on residential properties within the city. This is often determined based on GIS measurements using air photos. Non-residential properties usually have their impervious surface measured (using GIS) and their utility fee is set based on the number of ERUs they have (for instance if the ERU is 5000 square feet, and a commercial property has 50,000 square feet of impervious surface on it, their charge would be for 10 ERU or about 10 times that of a single family home owner). • Determine How Fees Will Be Collected – Utilities often have two choices for billing and collecting fees: billings, normally included with water or wastewater bills; or arrange (pay) for the County treasurer to send bills annually with the property tax statements. Which method is chosen has important implications for things like cash flow, enforcement mechanisms, public relations, and administration costs. An inter-local agreement is often needed between a city and a county for the later approach to work. • Establish a Customer Account Database – Set-up a customer account database to track account status and a system to track parcel ownership, development that results in changes to the land use, annexations, and so on. The City may already have much of this done depending on the status of water and wastewater billing systems. The database can be time consuming to set-up, particularly when it is necessary to measure impervious surfaces for commercial, industrial and/or residential properties. • Determine Disposition of Storm Drain Infrastructure – Determine who will own the storm drain infrastructure when the utility is formed. Often times all infrastructure becomes the property of the utility which affects its financial standing as well as makes it directly responsible for all O&M and project costs. Other times, road-associated drainage infrastructure remains the property of the Municipal Services Department and only non-road related infrastructure is owned by the utility. This can be important when deciding who will pay a share of O&M and project costs and the size of the resulting utility rates. • Establish Sound Factual Basis for Fees (Burdens, Services, Science) – Develop a written document that clearly demonstrates that the City conducted appropriate “due diligence” when deciding to enact the utility and establish rates on classes of customers. It is not uncommon to have legal challenges to stormwater utilities. Therefore it is prudent to be prepared to successfully defend the utility by clearly documenting that due diligence was performed and that the enacting ordinance considers and addresses the most recent legal decisions. Due diligence involves discussing the types of “burdens” (runoff, pollution) imposed by classes of customers (land uses), the services provided by the utility to each class of customer (public education, surface water quality protection, pollution ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-12 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc management, conveyance, safety, groundwater/drinking water quality protection, etc.), and how these directly relate to the rate structure and fees. This is also where credits and waivers should be justified. Referring to established science and engineering practice is an important part of conducting due diligence. • Educate the Pubic and Involve Key Stakeholders – Educating the public and involving key stakeholders early in the process of establishing a utility can decrease the odds of a legal challenge as well as decrease the magnitude of the inevitable outcry that will occur when the first bills are received by property owners. Be prepared to answer hard questions. Use fact sheets and other materials that discuss the need for the utility fee and the services and benefits that will be provided. Sometimes it is wise to meet one-on-one in advance with the 20 or so projected top fee payers. Involving special interest groups can be important as well, but can also serve to delay the process as it is not uncommon for them to directly lobby policy makers, and challenge all aspects of the work and the need for the utility. It is important to discuss public, stakeholder, and special interest group involvement and likely responses with the policy makers and develop a strategy for success. Communication (documented) of key points and issues is very important. It takes time to address the above items, so it is important to begin as soon as direction from policy makers indicates that a utility should be pursued. Given the potential for the City to be under an NPDES permit sometime in late 2006, efforts to form the utility should begin soon, if that is the funding mechanism chosen by the leaders. Estimating Estimating Estimating Estimating Approximate Approximate Approximate Approximate Surface Water Surface Water Surface Water Surface Water Utility Utility Utility Utility Rates Rates Rates Rates Given a financial plan and utility policies, the final step of the process is to translate the financial plan into surface water utility rates. For this preliminary analysis we will make the following assumptions: • The number of utility billing units will be based upon impervious surface with the ERU being equal to about 3600 square feet of impervious surface (same as the average for residential properties in the City of Yakima). • The ratio of total of billing units to total population is roughly the same as that found in the City of Yakima, which had about 49,000 ERU with a population of about 80,000 people. • Kennewick has an estimated 2005 population of about 60,000 people, from which it is estimated that about 36,750 ERU would be present. • Development permit fees will be neglected (or assumed to be part of the dependable existing revenue). In reality, utility rates can likely be lowered ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-13 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc if more funding is provided from increased development permit fees( as long as the permit fees are based on the actual cost). The use of stormwater utility fees to subsidize development review and site inspection costs should be avoided, therefore it will be important for the City to track development review costs and adjust permit fees accordingly. Approximate stormwater rates with and without CIP costs will be presented for each of 5 years for several funding alternatives which are described more below in Table 8-2. Table 8 Table 8 Table 8 Table 8-2 Funding Alternatives and Impacts on Existing City Funds and Possible Utility Funding Alternatives and Impacts on Existing City Funds and Possible Utility Funding Alternatives and Impacts on Existing City Funds and Possible Utility Funding Alternatives and Impacts on Existing City Funds and Possible Utility Rates Rates Rates Rates Funding Funding Funding Funding Alternative Alternative Alternative Alternative Desc Desc Desc Description of ription of ription of ription of Stormwater Stormwater Stormwater Stormwater Program Funding Alternative Program Funding Alternative Program Funding Alternative Program Funding Alternative Impact Impact Impact Impact on Existing City Funds on Existing City Funds on Existing City Funds on Existing City Funds & & & & Possible Future Utility Rates Possible Future Utility Rates Possible Future Utility Rates Possible Future Utility Rates Alternative #1 No new funding - fund and execute new and existing activities and projects by taking additional funds from sales taxes, general funds, wastewater, etc. and shift existing staff around as needed. This is essentially a “no utility” approach. Current funding is about $350k. Full program cost estimate is $1,410K adding $700K in regulatory costs + $360k/yr in CIPs. This would require approximately tripling the revenue from existing City funds over the next several years. There would be no utility fees. Alternative #2 New funding via a stormwater utility to cover the incremental new costs for projects, equipment, staff, and professional services. Assumes that the historic level of staffing and funding continue to be provided. This alternative assumes that $350k continues to be contributed from existing City funds. Utility rates are used to pay for new program and CIP costs. Utility rates for this option would be kept pretty low. Alternative #3 New funding via a stormwater utility to cover the entire SWMP costs and staff. The full cost of stormwater projects, equipment, staff, and professional services, will be covered by utility charges. This alternative assumes that no funding continues to be contributed from existing City funds, which allows those funds to be shifted to other City priorities. Utility rates are used to pay both existing and new program costs, plus CIPs. Utility rates for this option would be higher than in #2 but would likely still be reasonable compared to fees in other communities. The approximate annual Kennewick stormwater utility rates are shown below for Funding Alternatives 2 and 3, with and without CIPs in Tables 8-3 and 8-4, respectively. Given the substantial amount estimated for CIPs, the City may elect to ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-14 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc defer CIP budgeting for a couple years, keeping rates low until more is learned during field work. This also allows the City to focus on organizational issues and helps ensure that NPDES programmatic requirements are implemented successfully in early years. Table 8 Table 8 Table 8 Table 8-3 Funding Alternative #2 Rates Funding Alternative #2 Rates Funding Alternative #2 Rates Funding Alternative #2 Rates - Utility Paying Only New Costs, Utility Paying Only New Costs, Utility Paying Only New Costs, Utility Paying Only New Costs, With and Without CIPs With and Without CIPs With and Without CIPs With and Without CIPs Year 1 Year 1 Year 1 Year 1 Year 2 Year 2 Year 2 Year 2 Year 3 Year 3 Year 3 Year 3 Year 4 Year 4 Year 4 Year 4 Year 5 Year 5 Year 5 Year 5 Estimated Rates With CIPs ($/ERU per Mo.) $1.54 $1.81 $2.09 $2.13 $2.40 Estimated Rates W/O CIPs ($/ERU per Mo.) $0.73 $1.00 $1.27 $1.31 $1.59 Example Fees With CIPs Example Fees With CIPs Example Fees With CIPs Example Fees With CIPs Single Family Home $1.54 $1.81 $2.09 $2.13 $2.40 1 Acre Commercial* $16.79 $19.75 $22.72 $23.21 $26.17 10 Acre Industrial Site* $167.91 $197.53 $227.15 $232.08 $261.70 Example Fees W/O CIPs Example Fees W/O CIPs Example Fees W/O CIPs Example Fees W/O CIPs Single Family Home $0.73 $1.00 $1.27 $1.31 $1.59 1 Acre Commercial* $7.90 $10.86 $13.83 $14.32 $17.28 10 Acre Industrial Site* $79.01 $108.63 $138.25 $143.18 $172.81 *Assumes 90% Impervious Surface Table 8 Table 8 Table 8 Table 8-4 Funding Alternative #3 Rates Funding Alternative #3 Rates Funding Alternative #3 Rates Funding Alternative #3 Rates - Utility Paying Full Costs, Utility Paying Full Costs, Utility Paying Full Costs, Utility Paying Full Costs, With and Without CIPs With and Without CIPs With and Without CIPs With and Without CIPs Year 1 Year 1 Year 1 Year 1 Year 2 Year 2 Year 2 Year 2 Year 3 Year 3 Year 3 Year 3 Year 4 Year 4 Year 4 Year 4 Year 5 Year 5 Year 5 Year 5 Estimated Rates With CIPs ($/ERU per Mo.) $2.34 $2.61 $2.88 $2.92 $3.20 Estimated Rates W/O CIPs ($/ERU per Mo.) $1.52 $1.79 $2.06 $2.11 $2.38 Example Fees With CIPs Example Fees With CIPs Example Fees With CIPs Example Fees With CIPs Single Family Home $2.34 $2.61 $2.88 $2.92 $3.20 1 Acre Commercial* $25.43 $28.40 $31.36 $31.85 $34.81 10 Acre Industrial Site* $254.34 $283.96 $313.58 $318.51 $348.13 Example Fees W/O CIPs Example Fees W/O CIPs Example Fees W/O CIPs Example Fees W/O CIPs Single Family Home $1.52 $1.79 $2.06 $2.11 $2.38 1 Acre Commercial* $16.54 $19.51 $22.47 $22.96 $25.92 10 Acre Industrial Site* $165.44 $195.06 $224.68 $229.61 $259.23 *Assumes 90% Impervious Surface ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-15 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc Note that the accuracy of these estimated rates depends directly on the validity of the assumptions used. Differences in the actual number of City billing units (ERUs), definition of the ERU, and chosen City utility policies all have an impact on the size of fees. Comparison to Local Communities Comparison to Local Communities Comparison to Local Communities Comparison to Local Communities The above estimates provide a good foundation on which the City can make important decisions before undertaking the hard work necessary to actually adopt and implement a utility. The full program rates with CIPs (Funding Alternative are very reasonable when compared to rates used by agencies which have already implemented regulatory stormwater programs. Rates for such programs are commonly well over $6.00 per month/ERU, with it becoming more common to see rates over $10.00 per month per ERU. If the City chooses to formally compare proposed rates with those used in other communities, it is important that “apples are compared to apples”. It would not be accurate to compare the City’s estimated fully implemented regulatory driven program rates to the rates of a community that has not implemented a similar program. Many communities are not subject to NPDES or UIC and therefore have not implemented comprehensive stormwater programs. As such their utility rates are low (although often still higher than the estimates above). In addition, how the ERU is defined and how the rate is structured for different classes of customers also has an impact on the final rate for any given customer group. The current range of stormwater utility rates in the Northwest is from about $5 to $13 per month per ERU, with the median being about $7-$8 for most utilities in Western Washington. However, many of these existing utilities are currently undergoing regulatory gap analyses that will likely result in rate increases above existing levels. Conclusion Conclusion Conclusion Conclusion It is recommended that the City of Kennewick establish a city-wide surface water utility with service fees at an adequate level to fund new stormwater program projects and activities over the next five years. Once a stable financial rating is obtained, the utility may choose to establish bonding to help pay for its capital projects over a longer timeframe. (Note that it is common for fledgling surface water utilities to use the “pay-as-you-go” approach recommended in this financial plan to fund for CIPs for the first several years.) How soon the city needs to review and modify stormwater utility rates depends on how the City chooses to implement the utility fee. For instance, if the city chooses to ---PAGE BREAK--- Section 8 — Funding Alternatives and Financial Plan Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 8-16 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 8.doc implement a flat fee that will hopefully remain unchanged for the first 5 years, then rates should be reviewed after about three years to ensure consistency with current regulatory permit requirements, expected expenditures, and capital facility needs and priorities. However, if the City chooses to “ramp-up” the rates over 5 years, then it will be necessary to prepare subsequent year budgets and adopt rates every year (unless the law allows a multi-year “ramp-up” rate schedule and budget to be adopted). ---PAGE BREAK--- Section 9 — Public Involvement C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n 9-1 hdr/otak P:\07354_Kennewick\004979_stormwater_plan\6.0_engineering_design\6.7_studies\Final Apr 07\Section 9.doc Public Involvement Public Involvement Public Involvement Public Involvement: An Overview : An Overview : An Overview : An Overview The City of Kennewick has planned two public notices and two public input meetings surrounding the finalization of the Comprehensive Stormwater Plan. The public review period will begin after the City completes its full internal review of the draft plan. The two open house style public meetings will be held during evenings over a three week period. The focus of the meetings will be to solicit public comment and answer questions on the proposed plan. Meetings will be announced via public notices. Upon public notice of the meeting, the City will post a PDF version of the complete Draft Comprehensive Stormwater Plan or an Executive Summary on its City web-site. If only an Executive Summary is posted, copies of the full report will be available at the City and at the public meetings to ensure full public access to the document After conducting the public notice period and two evening meetings, the City will review and evaluate the recommendations and comments received from the public. Where possible, comments will be incorporated into the final plan. Once the appropriate revisions have been made to the Comprehensive Stormwater Plan, a final draft will be published by the City and forwarded to Washington State Department of Ecology for review and approval. Continued public involvement is a requirement of NPDES Phase II. Record keeping and program monitoring will need to be maintained on an annual basis to track and record public involvement notices, responses from public, and general participation with the City’s stormwater program. For the 5 year permit period, there are a number of required ordinances and minimum requirement programs that will need to be developed and adopted. Public workshops with the City Council are excellent opportunities to allow public participation with the stormwater program development. ---PAGE BREAK--- Appendix A — City’s Ordinances and Legal Authorities ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- ---PAGE BREAK--- Appendix B — Initial Data Request ---PAGE BREAK--- ---PAGE BREAK--- City of Kennewick, SWM Plan 1 Initial Otak Data Request City of Kennewick KENNEWICK STORMWATER MANAGEMENT PLAN INITIAL DATA REQUEST J. Simmler, Otak, Inc. Project Kickoff Meeting September 5, 2003 A. City Drainage Area Characterization Information (As/If available) Received Data Source: CAD CD: City of Kennewick AutoCAD Information (Muilleur, 11/5/03) Plan’90: Comp Flood Control and Storm Water Plan (Muilleur, 11/5/03) 11/5Memo: Storm Drain Prioritization Procedure (Muilleur, 11/5/03) Wellhead: Wellhead Protection Plan – Ranney Collector Wells 4 and 5 (Muilleur, 11/5/03) • City’s base map of study area received cad cd, Aaron is making a map for the facilities tour • Parcels (from City) CAD CD • Land use (from City) CAD CD • Topography and CAD CD • drainage sub-basins • GMA Land use boundary (within City and GMA) CAD CD • Existing and future land use and zoning CAD CD (2002 Land Use) • Soils (from City, County, other sources) • Roads (from City, County) CAD CD • Impervious areas CAD CD (structure/street) • Aerial photos, past flood photos • Climate (from City, County, Airport, and other local weather stations) • Rainfall (from County, Airport, and USGS) • Critical/Sensitive areas including • wetlands, floodplains, and fish and wildlife habitat areas; steep slopes, riparian corridors, groundwater recharge areas CAD CD • highly erodable soils and soils with high runoff potential; and • municipal drinking water sources (from City and County Critical Areas Maps and National Wetlands Inventory). Wellhead • Water bodies and waterways (from City, County) CAD CD • Drainage basins and sub-basins, including hydrologic features (from City, County) • Inventory of existing stormwater facilities and CAD CD • drainage areas/sub-basins (from City with some Field Survey Observations) • Groundwater/aquifer elevations and distributions ( from City, County and other sources, as available) ---PAGE BREAK--- City of Kennewick, SWM Plan 2 Initial Otak Data Request • Regulatory environment (from City, County, Ecology, NMFS, etc.) • A map of jurisdictional boundaries including GMA (from City, County) CAD CD • Existing and future land use within the SWM Planning Area (from City) CAD CD (2002 Land Use) • Floodplains and floodways (from FEMA, City and County) CAD CD (100-year) • Water quality monitoring data, and stream gauging flow data (from City, other sources?) • Other information needed to complete an accurate description of the basin (from other sources, as available and as budget allows). B. City SWM Program Information (As/If available) Other types and sources of stormwater information needed from the City include the following: • Stormwater Program Management and Financing Information - Annual budget, staffing, organization chart, and annual program priorities, - Last 2 to 3 years of operating and CIP budgets, - Revenues and expenditures by activity operating and capital), - List of any current or requested grants or loans, - List of program problem areas and/or needs what is not getting done, or done well, and what needs to be done better?), - Copies of stormwater-related ordinances, Plan’90 (Exhibits) - Any existing local agreements regarding drainage flood control zone districts, etc.). • Stormwater Technical Information - Prioritized list of capital needs and costs, if applicable. 11/5Memo Plan’90 (CIP List) - Past drainage studies or SWM Plans Plan’90 Wellhead - Drainage complaints, maintenance records, and past studies (from City and County?) - List and location of flooding problem areas. - Copy of annual O/M Plan, including staffing levels, equipment rentals/purchases and costs. - Copy of stormwater design standards, bulletins, brochures, etc. - Existing water quality data. - Copies of any state violations, including compliance orders, NPDES permits, etc. - Hydrologic/hydraulic data – rainfall, stream flow, etc. Past hydrologic/hydraulic modeling and data bases. - As-built drawings of major drainage facilities (as/if needed). ---PAGE BREAK--- City of Kennewick, SWM Plan 3 Initial Otak Data Request - History of spills and/or water quality violations by local businesses, - Also any records of water quality monitoring by Ecology. C. County Information (As/If Available) Additional data that may be available from the county and other sources will be included in the drainage area characterization. This data may include: • Digital and hard copy aerial ortho-photograph of the stormwater planning area, showing existing land uses. • Topography: Digital and hard copy topographic contour information of the SWM Planning area, and of the affected watersheds. This topographic information will be formatted to fit exactly on top of the aerial ortho-photograph provided above. • Watershed and drainage sub-basins boundaries for each of the three watersheds within the SWM Planning study. • Additional sensitive areas data, including wetlands, floodplains, and fish and wildlife habitat areas; steep slopes, riparian corridors, groundwater recharge areas, highly erodable soils and soils with high runoff potential; and municipal drinking water sources • Soils • Roads • Waterbodies and waterways • Drainage basins and sub-basins, including hydrologic features • Groundwater/aquifer elevations and distributions • A map of jurisdictional boundaries, existing and proposed land use and zoning, including GMA areas within the three affected watersheds in the study area. • Existing and future land use in the three watersheds D. Existing Reports and Documents: • City Documents: - Land Use/Zoning Plan - GMA Plan - Capital Improvement Plan - Comprehensive Water Plan - Comprehensive Sewer Plan - Stormwater Plan (if available) or any Drainage Studies - Annual Budgets for 2003 and 2004 • County Documents: - GMA Plan - Water Plan - Sewer Plan - Groundwater Plan ---PAGE BREAK--- City of Kennewick, SWM Plan 4 Initial Otak Data Request - Aquifer Protection Plan - Stormwater Plan - Land Use Plan - Infrastructure Capital Plan - Conservation District Studies - Relevant Watershed Action Plans - Flood Hazard Reduction/Mitigation Plans • Federal/State Documents: - CORPS, FEMA, etc. - DNR, Fisheries, etc. - Other Sources of Drainage Information: - Private industries - Tribes - Environmental groups - Ports ---PAGE BREAK--- Appendix C — December 18, 2003 Site Visit: Meeting Minutes ---PAGE BREAK--- ---PAGE BREAK--- K:\project\30300\30386\Reports\Final Report\Appendices\Appendix C - SiteVisit_121803.doc A r c h i t e c t s E n g i n e e r s L a n d s c a p e A r c h i t e c t s P l a n n e r s S c i e n t i s t s S u r v e y o r s U r b a n D e s i g n e r s Meeting Minutes Meeting: City of Kennewick, Staff Interview Project No.: 30386 Meeting Date: December 18, 2003 Meeting Time: 10:45 AM – 12:00 Noon, Staff interview 1:00 PM – 5:00 PM, Field Tour Location: City of Kennewick 620 Kirkland Way, #100 Kirkland, WA 98033 Phone (425) 822-4446 Fax (425) 827-9577 Attendees: Aaron and Roy of HDR; Lee, Bill, Dave, Gary, Steve, Bruce, and Cindy of Kennewick; Ed, Joe and Laura of Otak Minutes By: lcb According to the City, the worst flooding problems have already been addressed. The City’s CIP list has some problem locations listed, but they are primarily smaller, localized nuisance flooding, slow drainage areas and maintenance issues. Several flooding problems were fixed after the large storms in 1996. Steve says there have not been big enough rains since the 1996 floods to adequately test the improvements. Hydraulic modeling may predict new areas of concern. New developments may also result in new problem areas. Models developed under this project will analyze final build-out conditions within the Urban Growth Boundary, and check for upstream and impacts. City maintenance crews: • Began blocking water going to the sewer four or five years ago. 99% of the storm is separate from the sewer. • Have a list of 15 problem areas they serviced during recent high rains (1-inch in 24 hours). − The City will provide this list to HDR. • Perform annual dry well and catch basin maintenance. They carry a lap top computer with them to take GIS inventory. Inverts are measured down from the rim using a tape measure. Rim elevations are from 2-foot contours, therefore are not very accurate. A copy of the inventory sheet they use was provided during the interviews (see attached). The catch basin documentation should be complete by the end of December. TV-ing the storm system to document the pipes is scheduled to begin in January 2004. The TV-ing will take 2-years to complete. − Aaron will coordinate with Steve on how to get available stormwater inventory, and O/M information into a useable format. Information will be helpful to Aaron with the modeling and to Otak in writing the Comprehensive Stormwater Plan. ---PAGE BREAK--- Meeting Minutes December 18, 2003 Page 2 K:\project\30300\30386\Reports\Final Report\Appendices\Appendix C - SiteVisit_121803.doc A r c h i t e c t s E n g i n e e r s L a n d s c a p e A r c h i t e c t s P l a n n e r s S c i e n t i s t s S u r v e y o r s U r b a n D e s i g n e r s • Are in the process of prioritizing their maintenance schedule. A 1-5 rating system (5 being the worst) is used to rate the storm system condition. There is no written documentation explaining the 1-5 rating characteristics. Attributing the GIS information is in progress. − Aaron will acquire a rated and prioritized O/M schedule of activities from the City. • The City runs three vactor trucks, five days per week. Last year’s sweeping collected 3,000 tons of material to dispose of at a transfer station. Arterial streets are swept every other week – half are swept one week, with the other half swept the next week. Residential streets are swept four times per year. Streets are washed prior to cleaning out the catch basins. If catch basins on their cleaning schedule are blocked by parked cars, maintenance crews return at a later time to ensure each catch basin gets cleaned. Announcing the street-sweeping schedule in advance to prepare locals is difficult to accomplish in some areas. − Aaron will acquire a map of areas swept. • A maintenance organization chart is in flux. Steve has work order numbers to track time and budget for stormwater related activities. • The golf course settling basin requires maintenance every 2-years to remove sediment. • $100,000 per year is spent for flooding improvements. Irrigation: • KID irrigation tailwaters existed prior to the roads and improvements. Irrigation has historical precedence because the City has built roads and homes in the irrigation’s natural drain path. Little documentation on the matter exists. Some irrigation districts have easements. • KID does not want City flow in ditches above a certain size storm. • Some catch basins get sedimentation from irrigation ditches, but overall, irrigation sedimentation is not a large problem. • The City preference is to leave matters with the Irrigation District the way that they are. Creating a list of existing locations where irrigation ditches discharge into the river (dump spots) is a good way to document what dump spots have historical rights and to identify new dump spots so the new dump spots can be regulated. − The City has a map of CID and KID discharge locations. The map will be shared with HDR and Otak. Aaron to follow up with the City. • Garfield ditch is the only real problem location. There is a pump station and weir located near the school, the weir is in the ditch and creates a conveyance backwater during big rains. Garfield ditch infiltrates and never reaches the river. • Water quality is a potential issue in the ditches, but has not been documented. • CID is designed to operate with a BFD pump. The irrigation district delivers a fixed quantity of water. When big rains occur and irrigation use declines, the pumps spill irrigation water into the storm system. • The City does not have the funding available to remove existing irrigation canal connections to the City storm system. No new connections should be allowed. ---PAGE BREAK--- Meeting Minutes December 18, 2003 Page 3 K:\project\30300\30386\Reports\Final Report\Appendices\Appendix C - SiteVisit_121803.doc A r c h i t e c t s E n g i n e e r s L a n d s c a p e A r c h i t e c t s P l a n n e r s S c i e n t i s t s S u r v e y o r s U r b a n D e s i g n e r s • Irrigation sprinklers are pressurized. The irrigation season is April 15 – October 15. More irrigation spills occur during this time frame because less irrigation water is needed. Irrigation discharge to the City’s storm system also occurs in the fall when irrigation pressure lines are drained so they will not freeze. Most irrigation overflows end up in a lower irrigation ditch or as a tailwater back into the ditch, but some spills into the City storm system. The fall blow off is out of a 4-inch pipe for about 8 hours; therefore, capacity is not the issue. The water is screened, but the screens are 1/8-inch screens and allow seeds through. • The City made the decision to keep stormwater out of the irrigation ditches and keep the two systems separate. The City wants to understand: • The City’s risk, with regards to irrigation water. The City wants to maintain a good working relation with the irrigation districts. • Future irrigation connections should be subject to City review. This should be addressed in the Comp. Plan. • The long term results of the existing connections to irrigation canals. • What regulatory issues are there? • How does Washington State view irrigation canals? Are they waters of the state? Other illicit connections: • Storm catch basins in the old areas of Kennewick overflow and spill into the sanitary sewer. Exact locations may not be known until TV-ing is complete (two years from now). • Illicit connections are more likely from roof drains and parking lots than from industry waste. • The airport water infiltrates. The airport is private, and not on the City storm system. Monitoring: • The City collected limited water quality data in the CID canal by Columbia Park. • Fisheries took some temperature readings. • The City is reluctant to take water quality data. It is unknown if Ecology has initiated any water quality studies. • There are no flow gauges. • Cindy has pump records from the irrigation districts. • Larry Fox, CID, wants to get grant money for a study in the Haxton drainage district. • Many of the catch basins in Kennewick are intentionally surcharged to limit the number of new outfalls and minimize future outfall/monitor locations. There are currently eight outfall locations to the river to monitor. Surcharging has not caused significant flooding. Flooding, Mollins Street in 1996, resulted from the surcharge during a 50-year event. • Monitoring could increase liability. Approved BMPs should be used where practical. ---PAGE BREAK--- Meeting Minutes December 18, 2003 Page 4 K:\project\30300\30386\Reports\Final Report\Appendices\Appendix C - SiteVisit_121803.doc A r c h i t e c t s E n g i n e e r s L a n d s c a p e A r c h i t e c t s P l a n n e r s S c i e n t i s t s S u r v e y o r s U r b a n D e s i g n e r s Local Regulatory contacts: Hoffer – Local Fish Biologist LaRiviere – WDFW Public Education: • Overwatering is causing problems with drywells. Overwatering causes the drywells to silt up and require more frequent vactor maintenance. Overwatering becomes groundwater, not runoff. Public education for water conservation could be a component of the stormwater plan. • Locals are encouraged to drain their pools into their yards, opposed to into the storm drain system. However, upon request, the City will check local storm drain capacity and allow pools to discharge to the storm drain system. • Car oil in storm drains is a problem. The Army Corp., the City, and the Tribes control the riverfront: The levee along the Columbia River was over-designed by the Corp of engineers. The levee will be lowered 6-feet for aesthetic purposes. The material excavated will be used as fill in the ditch, also designed by the Corp, behind the levee. No increased flooding is anticipated from lowering the levee. The ditch east of the cable-bridge will be used as storm conveyance. The Columbia River flooded the entire park 2-feet deep during a large event that caused a back up in Portland. The park flood was controlled by Dams to alleviate problems in Portland. The City has 4 ponds that they are responsible to maintain. • Duffy’s Pond is an area of concern. It may have water quality issues. The pond is a possible source of future irrigation. • 60-inch inflow pipe. • There is a pond that will be considered waters of the state. The pond is a source of irrigation water. Smolt can enter the pond for rearing. Screens are place such that no adult fish will enter the pond. • There are problems at the west side outlet – west of Columbia Center Boulevard. The Columbia Mall pond fails. Water overflows to a ditch and flows through a culvert under the railroad into the Richland Home Depot. The pond does not belong to the City, but has become a City problem. There was a lawsuit. City Storm System: • The City prefers to infiltrate all stormwater into drywells. There are 2,000 drywells in the City. Drywells are relatively easy to maintain and are aesthetically pleasing. Drywells are covered with a concrete caps and manhole. Drywells are typically 14-feet deep. Some parts of the City have soil that is too tight to infiltrate within 72-hours. ---PAGE BREAK--- Meeting Minutes December 18, 2003 Page 5 K:\project\30300\30386\Reports\Final Report\Appendices\Appendix C - SiteVisit_121803.doc A r c h i t e c t s E n g i n e e r s L a n d s c a p e A r c h i t e c t s P l a n n e r s S c i e n t i s t s S u r v e y o r s U r b a n D e s i g n e r s − Steve will provide Aaron a map of tight soil locations. Aaron will provide Otak with a copy of the map for Underground Injection Control compliance purposes. Trench drains are no longer exempt from UIC. • Drywell details are available at the City’s web page. • Infiltration test procedures are in the City’s standard drawings. Test procedures are also in the 1990 Comp. Plan. • Closed depressions and poor infiltration areas created from future development should be mapped. • The City believes they are currently in regulatory compliance with their stormwater system, this should be documented. • The City doesn’t allow developments to connect to the City storm system. Developments must infiltrate the 10-year storm on-site. • Ditches are avoided because of trouble with mosquitoes. • The Comprehensive Flood Control and Storm Water Drainage Plan, JUB 1990, has response-action plans. BMP: Add 20-acre to Columbia Park and irrigated it with collected stormwater from supplemental river water when needed. The collected stormwater from urban areas can be used as irrigation water in the park. What are the water rights issues? What is the practicality of such a system? Groundwater and Aquifers: The Wellhead Protection Plan, Ranney Collector Wells 4 and 5, Golder 1997, discusses aquifers and depths of groundwater. Groundwater is typically 25-feet below the surface, except for downtown. Randy Brown knows about the depth of groundwater. Roy has the phone number for Mark Cunnane. Bruce has a map of wellhead depths. Well information is available on-line from Ecology. Benton County: The aerial photograph was taken in 1998 WSDOT: Not much activity. Their runoff infiltrates in ditches. Issue Date: January 12, 2004 By: lcb ---PAGE BREAK--- ---PAGE BREAK--- Appendix D — Regulatory Compliance Analysis ---PAGE BREAK--- ---PAGE BREAK--- Appendix D.1 — Existing Stormwater Program ---PAGE BREAK--- ---PAGE BREAK--- Appendix D.1 — Existing Stormwater Program C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.1-1 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D1 - Ex SWM Prog-JHK.doc Introduction A critical element to the development of a comprehensive stormwater plan for the City of Kennewick is the evaluation of the City's existing surface water program, and a comparison of that program with Federal and State regulatory requirements. For the City of Kennewick, this Regulatory Compliance Analysis has been developed and completed in three parts: • Part I — Documentation and analysis of the City's existing stormwater program • Part II — Preliminary comparison of the City's stormwater program with NPDES II requirements • Part III — Regulatory gap analysis and recommended compliance strategy This Part I analysis documents the City's existing surface water program activities, staffing, and funding levels. This evaluation is based on data and documents received from the City, interviews with City Staff, site visits, the results of a regulatory compliance questionnaire, and a review of the City’s March 2003 NPDES II Permit Application. This analysis will be used as the basis for preparing the regulatory gap analysis, which compares the various stormwater regulatory requirements with the City’s existing stormwater activities. City's Existing Surface Water Program Responsibilities The City of Kennewick Municipal Services Department manages the City’s stormwater program and drainage facilities. The direction of the program is determined by the Director of the Public Works Division, who delegates much of the responsibility to the City Engineer. The City Engineer is responsible for the City’s Stormwater Program, staff, annual work program and activities. Much of the day-to- day direction of the Program, however, is further delegated to a Senior Project Engineer, who often gets his guidance directly from the Public Works Director. The City’s Stormwater Program is funded on an annual basis from a compilation of sources including the City’s Street Department and Water/Sewer Department. Capital projects for storm drainage are funded out of the City’s 0.5% sales tax. Annual Budget Revenues, allocated to the City’s Stormwater Program, amount to about $400,000 per year on average. In the 2004 budget, about $73,000 of this amount has been allotted for labor, benefits, and expenses from the Street Fund. This includes general storm drainage maintenance ($20,000) and source control through street sweeping ($53,000). An additional $131,000 is budgeted from the Water/Sewer Funding for Dry Well/Catch Basin Cleaning ($106,000), Storm Drainage Repairs & Flood Control ---PAGE BREAK--- Appendix D.1 — Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.1-2 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D1 - Ex SWM Prog-JHK.doc ($15,000), and Inventory & Detection ($10,000). The remaining $200,000 goes toward the design and construction of capital projects, as annual funding allows. Activities The maintenance services of the Stormwater Program are internally performed by the City’s Maintenance and Operations (M/O) Division, within the Public Works Department and the Parks, Streets, and Facilities Division (Facilities). Both divisions are located within the Municipal Services Department. Management and direction of annual stormwater maintenance activities is a shared responsibility of the Public Works M/O Manager and the Facility and Grounds Supervisor. Much of the day-to-day management responsibility is delegated to the lead crew foremen within each of these two divisions. Day-to-day drainage maintenance services are provided by a 2-3 person maintenance crews, who operate the vactor trucks, conduct street sweeping, and respond to complaints and other drainage emergencies. Capital Improvements The City has a small, pay-as-you-go, annual capital improvement fund (about $200,000 per year) for the construction of new facilities, or the repair and/or replacement of older or damaged facilities. The amount of funding available for capital projects varies from year to year. For this reason, many of the City’s current stormwater facilities are designed and constructed in conjunction with road and/or other utility infrastructure projects. New developments are also often requested to upgrade and/or replace existing undersized drainage facilities for the City as a condition of their permit approval. Staffing About 3.5 full time equivalent (FTE) staff support the City’s Stormwater Program on an annual basis. Most of the drainage staff are located within the Municipal Services Department, with 1.5 FTE in Engineering and 2.0 FTE in Maintenance. A small amount of support is also provided by the Community Development Department (Planning) and the Finance Office throughout the year, on an as-needed basis. Equipment and Materials At this time, the City’s Stormwater Program exists as a series of services that are provided by staff from several divisions within the Municipal Services Department. There is no separate Stormwater Division. As such, equipment, vehicles, and materials must be rented from the City’s Public Works M/O Division and the Facilities Division on an as-needed basis. Annual stormwater maintenance activities, equipment and materials include the following. • Catch basins and dry wells are routinely cleaned by the two vactor trucks located within the City’s Streets and Sewer Programs. Recently, two new vactor trucks ---PAGE BREAK--- Appendix D.1 — Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.1-3 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D1 - Ex SWM Prog-JHK.doc have been purchased by the Wastewater Fund. The older vactor truck was retired. • Arterial roads are swept every three weeks and residential streets are swept by the City’s vacuum sweepers quarterly. There are currently three vacuum sweepers in operation. • Replacement culverts and other tools and materials needed for maintenance, repair, and replacement of stormwater facilities are purchased as needed through one of the two maintenance divisions’ annual budgets. • The city operates a street waste facility which handles street sweeping wastes and dry well cleaning wastes. Materials collected at this facility are tested for RCRA metals and TPH. If these wastes are within MTCA limits, they are disposed of at the inert landfill. There have been no instances in which the MTCA limits have been exceeded since testing originated in 1993. Ordinances and Legal Authorities The City of Kennewick routinely enforces an array of ordinances, guidelines and practices related to stormwater management. Stormwater management is addressed by the following ordinances as described in the Kennewick Municipal Code (KMC). Many of these ordinances are related to the City’s sanitary sewer system and the City’s development review and approval processes. Chapter KMC: 4.04 – Administrative Appeals 4.08 – State Environmental Policy Act 4.12 – Permit Process 5.56 – Public Works Construction Standards Section 7-1 - Specs for Storm Drain (Pipe) Section 7-2 - Trench Excavation and Backfill Section 7-3 - Imported Pipe Bedding Section 7-4 - Catch Basin Section 7-5 - Standard Manhole Section 7-6 - Standard Drywell Section 7-7 - Drywell Percolation Tests Section 7-8 - Abandoned Conduits Section 7-9 - Catch Basin Protection Section 7-10 - Storm Drain Design 9.48 – Nuisance Law 14.22 – Sewerage Services 14.24 – Sanitary Sewerage Connection Charges 14.26 – Sanitary Sewer User Charges 14.28 – Storm Sewer Charges 14.30 – Sewer Backup Prevention ---PAGE BREAK--- Appendix D.1 — Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.1-4 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D1 - Ex SWM Prog-JHK.doc 15.41 – Cross-Connections (to the City’s Water System) 18.06 – Districts and Maps 18.89 – Administration and Enforcement 18.92 – Shoreline Management 18.93 – Flood Damage Prevention The City has the ability to review and revise these legal ordinances and standards, as well as create new ordinances, as necessary. Of particular note, KMC 14.28 Storm Sewer Charges has been in effect since 1976 and the City has elected not to levy the storm fees. Analysis of Existing Stormwater Program Otak conducted a detailed review of the City’s existing stormwater program. The analysis covers 21 elements that make up a typical stormwater program. These are the elements that will likely be needed for compliance with regulatory compliance, including the NPDES Phase II municipal stormwater permit. Existing responsibilities, staffing levels, and current annual funding were identified for each program area. In some cases, the City does not have any staff or funding assigned to a particular element of the program. The analysis includes documentation of revenue sources, and which elements of the Kenmore Municipal Code give regulatory authority to the City. Table 1 shows the detailed analysis of the City’s existing stormwater program. The following observations have been made in reviewing the City’s existing stormwater program: • The current SWM program supports 3.5 FTE staff (primarily in O/M) and provides the revenue for $417,000 in labor/benefit costs and other program related expenses. • New federal and state regulations will require the City to enhance its existing stormwater program. • The City’s existing sources of revenue for SWM activities come from the street fund, the water/sewer fund, and the City’s 0.5% stales tax. These existing sources of revenue may not be able to meet all the regulatory standards. To date, the City has elected not to form a stormwater utility or levy stormwater fees. • While the City has already addressed the worst of its flooding problems, there are still 10-15 routine maintenance problems that will require small capital solutions. • The city does not currently have published O/M standards or a written annual plan. ---PAGE BREAK--- Appendix D.1 — Existing Stormwater Program Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.1-5 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D1 - Ex SWM Prog-JHK.doc • A portion of the City’s sales tax is allocated to address current O/M needs. The SWM program is well funded for the current level of O/M services. However, the city does not have funds to repair or replace aging stormwater infrastructure, other than on an emergency basis. This is a future financial liability. • A public involvement and education program is needed to educate citizens and business owners about their impacts on stormwater discharge and groundwater quality. • Developer/contractor education materials would also be helpful and is required to achieve regulatory compliance. • The City’s current inspection for new construction should be reviewed and may need to be enhanced to improve enforcement of water quality and erosion guidelines. • Emergency response is primarily to overflowing drywells and other public complaints. Additional training and equipment may be needed to improve the response to water quality concerns and spill incidents. • While the City is part of the WRIA 31 Watershed Planning project, little regional or inter-governmental coordination related to stormwater is active at this time. The City staff have shown interest in increasing regional cooperation as a way to share technical expertise and reduce future costs of regulatory compliance. • The Community Planning department currently oversees and implements the Growth Management Plan, including development review and critical areas protection. Additional coordination between Planning and the Municipal Services Department SWM program is needed to address regulatory compliance requirements. • The need for stormwater technical expertise will likely increase as the City adopts the Stormwater Management Manual for Eastern Washington. • Any needed UIC compliance activities will need to be closely coordinated with the City’s existing Wellhead Protection Plan/Program. • The City does not anticipate ESA issues playing a significant role in future regulatory compliance activity. • Equipment and vehicles are rented and/or replaced on an as needed basis through operating agreements with the City’s other major infrastructure divisions (water, wastewater, parks, and streets). The City recently purchased two new vactor trucks and retired the older vactor truck. There are currently three vacuum sweepers in operation. • The City’s existing stormwater ordinances will need to be reviewed and updated as new regulatory compliance conditions are presented with the NPDES II and UIC guidelines. • Current legal guidance is obtained from the City Attorney on an as needed basis. This need may increase during the review and update of City ordinances. ---PAGE BREAK--- ---PAGE BREAK--- Regulatory Compliance Analysis – Part I Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.1-6 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D1 - Ex SWM Prog-JHK.doc Table 1 Summary of City’s Existing Stormwater Program Annual Level of Staff Effort (FTE) Annual Level of Funding Surface Water Program Elements Responsible Department Responsible Manager Assigned Staff FTE Hours Labor benefits) Expense Source(s) of Revenue Legal Authority / Ordinances Activities and Major Accomplishments Comments / Need for Enhancement (To address Local SWM Needs) 0.05 0.05 0.05 0.05 — 100 100 100 100 — $7,335 $,6816 $6,815 $4,960 $0 — — — — — 1. SWM Program Management, Funding, and Administration Public Works (Engineering Division) Director, City Engineer, & O/M Manager P.W. Director, City Engineer, O/M Manager, Eng. Staff, & O/M Staff 0.20 400 $25,923 $0 Annual allocations from the City’s Street Department (and Water/Sewer Department) and the City’s 0.5% Sales Tax KMC 14.28 The Stormwater program, primarily O/M, supports 3.50 staff and provides the revenue for $404,000 in labor/benefit costs and other program related expenses (2004 budget). New Federal and State regulations will require the City to enhance its existing SWM Program. Existing sources of revenue may not be able to meet current regulatory standards. Note: Storm sewer charges (KMC 14.28) have been in effect since 1976, however, the City has elected not to form a storm water utility and apply storm water fees. 0.05 0.05 100 100 $6,816 $4,960 — $42,946 2. Capital Improvements (for SWM) Public Works (Engineering Division) City Engineer City Engineer Eng. Staff 0.10 200 $11,776 $42,946 City’s 0.5% Sales Tax (Dedicated to the Street Fund: it includes annual SWM expenses.) KMC The City staff believes that the city has already addressed the worst of its flooding problems. The City has a small annual CIP program and responds to complaints and other drainage emergencies, on an as-needed basis. There are 10-15 routine maintenance problems that will require small capital solutions. 0.05 0.10 0.05 1.70 100 200 100 3,400 $6,816 $13,630 $4,960 $138,890 $42,602 — — — 3. Maintenance (of SWM facilities) Public Works (Maintenance and Operations Division) Maintenance Manager City Engineer, O/M Manager, Eng. Staff O/M Staff 1.90 3,800 $164,796 $42,602 Annual allocations from the City’s Street Department and Water/ Sewer Department KMC The SWM program is well funded for its current level of O/M services. Catch basins and drywells are routinely cleaned by the City’s two vactor trucks (shared by the City’s Streets and Sewer Programs). Arterial roads are swept every three weeks and residential roads are swept by the City’s vacuum sweepers quarterly. Materials collected are tested to RCRA metals and total petroleum hydrocarbons (TPH) and disposed of properly. Crews have inventoried and mapped the storm system using a GIS database; updates occur on a regular basis The City currently has no O/M standards or annual written O/M plan. A portion of the City’s 0.5% sales tax is allocated to SWM to address current O/M needs. However, additional funds and possibly new funding sources may be needed to address new NPDES II O/M requirements and the future costs associated with vehicle repair and replacement. Note: The City has no funds to repair or replace the City’s SWM infrastructure as it continues to age, other then on an emergency basis. This is a future financial liability for the City’s SWM Program. 0.05 0.30 100 600 $6,816 $29,760 — — 4. Development Review, GMA, & Design Standards Community Planning and Public Works Public Works on Design Standards) Directors: Community Planning & Public Works City Engineer, & Eng. Staff 0.35 700 $36,566 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department KMC 5.56 Planning Dept. manages the development review process, performs zoning reviews, participates in regulatory compliance activities, and provides some regional planning coordination. City Engineer examines permit applications (KMC 5.56). This activity could be totally fee supported. ---PAGE BREAK--- Regulatory Compliance Analysis – Part I Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.1-7 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D1 - Ex SWM Prog-JHK.doc Table 1 (cont.) Summary of City’s Existing Stormwater Program Annual Level of Staff Effort (FTE) Annual Level of Funding Surface Water Program Elements Responsible Department Responsible Manager Assigned Staff FTE Hours Labor benefits) Expense Source(s) of Revenue Legal Authority / Ordinances Activities and Major Accomplishments Comments / Need for Enhancement (To address Local SWM Needs) 0 0 $0 — 5. Public Education & Involvement (for SWM) Community Planning & Public Works Directors: Community Planning & Public Works Staff, as assigned 0 0 $0 $0 — — The City currently has no regular public education/involvement program. Public education and involvement will need to be established and regularly conducted to achieve regulatory compliance. 0.25 500 $24,800 — 6. Inspection & Enforcement for New Construction (for SWM) Community Planning Directors: Community Planning & Public Works Eng. Staff 0.25 500 $24,800 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department KMC 5.56.440 The City Engineer (through inspectors) checks work during construction (KMC 5.56.440). Current levels of SWM, WQ, and erosion inspection should be reviewed and may need to be enhanced in the future to achieve regulatory compliance. Current codes and ordinances should also be reviewed and may need to be updated. Developer / Contractor educational materials would also be helpful, and will be required to achieve regulatory compliance. 0.10 200 $8,170 — 7. Compliant & Emergency Response (for SWM) Public Works Public Works Director & O/M Manager O/M Staff 0.10 200 $8,170 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department — City normally gets about 10-20 complaints per year. Performed on an as needed basis. WQ, spill, and emergency response (staff, training, and equipment) will need to be reviewed and may need enhancement to meet regulatory NPDES II requirements. 0 0 $0 — 8. Regional Watershed & Inter-City Planning (for SWM) Public Works (Included in SW Element Public Works Director (Included in SW Element Staff, as assigned (Included in SW Element 0 0 $0 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department — Performed on an as-needed basis. City is currently updating their comprehensive stormwater management plan. 0 0 $0 — 9. Critical Areas, Wetlands, Flood Plains, Habitat, Groundwater, & Aquifer Recharge (for SWM) Public Works & Community Planning Directors: Community Planning & Public Works Engineering & Planning Staff as assigned. 0 0 $0 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department KMC Community Planning implements the City’s Growth Management Plan, and in so doing manages the development review process, performs zoning reviews, participates in regulatory compliance activities, and provides some regional planning coordination. There is a need to increase coordination between Planning and the City’s SWM Program to address regulatory compliance requirements. Check the City’s Wellhead Protection Plan. 0.10 200 $9,920 — 10. Engineering Technical Support to other City Departments (for SWM) Public Works (Engineering Division) City Engineer Eng. Staff 0.10 200 $9,920 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department — Performed as needed. The need for internal SWM technical expertise will likely increase as the City adopts the E.Wa. SW Design Manual and moves toward regulatory compliance. ---PAGE BREAK--- Regulatory Compliance Analysis – Part I Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.1-8 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D1 - Ex SWM Prog-JHK.doc Table 1 (cont.) Summary of City’s Existing Stormwater Program Annual Level of Staff Effort (FTE) Annual Level of Funding Surface Water Program Elements Responsible Department Responsible Manager Assigned Staff FTE Hours Labor benefits) Expense Source(s) of Revenue Legal Authority / Ordinances Activities and Major Accomplishments Comments / Need for Enhancement (To address Local SWM Needs) 0.10 200 $9,920 — 11. Regional Coordination (for SWM) (County, Cities, & Developers) Public Works Public Works Directors Eng. Staff 0.10 200 $9,920 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department — City has limited participation in regional stormwater activities. Past involvement relates to WRIA #31 activities. Some coordination has been occurring in regard to regulatory compliance for NPDES II, ESA, and UIC. Discussions with City staff show an interest in increasing regional cooperation as a way to share technical expertise and reduce future costs of regulatory compliance. Inter-local agreements for the sharing of equipment, staff, and services are possible. This may require additional staff time. 0.15 300 $14,880 — 12. NPDES II Regulatory Compliance Public Works Director & City Engineer Eng. Staff 0.15 300 $14,880 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department — City has submitted a Notice of Intent to Ecology per the March 10, 2003 due date defined in the Federal NPDES II requirements. City is currently not in compliance with NPDES II requirements. NPDES II compliance plan and schedule will be provided in the City’s updated Comprehensive Stormwater Management Plan. The draft permit for E.Wa. will be published in the summer of 2005, and the permit will go into effect during the summer of 2006. Note: There is an annual permit compliance fee of about $20K - $40K. 0.10 200 $9,920 — 13. UIC Regulatory Compliance Public Works Director & City Engineer Eng. Staff 0.10 200 $9,920 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department — This activity will be closely coordinated with the City’s Wellhead Protection Plan Program. UIC compliance plan and schedule will be provided in the City’s updated Comprehensive Stormwater Management Plan. 0.05 100 $4,960 — 14. ESA Regulatory Compliance Public Works & Community Planning Public Works & Planning Director’s Eng. Staff 0.05 100 $4,960 $0 — KMC 4.08 The City has not yet completed a review of its ESA obligations. However, the City believes its responsibilities will be minor. City staff do not anticipate any major ESA compliance efforts or expenditures in the future. 0 0 $0 — 15. Funding, Budgeting, Rates, Debt, & Taxes Public Works (Included in SW Element Public Works Directors (Included in SW Element Staff, as assigned (Included in SW Element 0 0 $0 $0 — The City’s SWM activities and CIPs total $404K annually and are currently funded from the following sources: street fund, water/sewer fund, and 0.5% sales tax. Funding may be an issue if a new SWM program is created and new funding and debt need to be incurred for regulatory compliance and capital projects. A stormwater utility fee should be considered. ---PAGE BREAK--- Regulatory Compliance Analysis – Part I Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.1-9 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D1 - Ex SWM Prog-JHK.doc Table 1 (cont.) Summary of City’s Existing Stormwater Program Annual Level of Staff Effort (FTE) Annual Level of Funding Surface Water Program Elements Responsible Department Responsible Manager Assigned Staff FTE Hours Labor benefits) Expense Source(s) of Revenue Legal Authority / Ordinances Activities and Major Accomplishments Comments / Need for Enhancement (To address Local SWM Needs) 0 0 $0 — 16. Equipment (for SWM) Public Works (Included in SW Element Maintenance Manager (Included in SW Element Staff, as assigned (Included in SW Element 0 0 $0 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department — The City recently purchased two new vactor trucks with the Wastewater Fund and retired the older vactor truck. There are currently three vacuum sweepers in operation. Equipment and vehicles are rented and / or replaced on an as needed basis through jointly developed, annual operating agreements with the City’s other major infrastructure divisions (water, wastewater, parks, and streets). 0 0 $0 — 17. Repair & Replacement (of SWM facilities and equipment) Public Works Maintenance Manager — 0 0 $0 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department — Replacement/repair costs are not routinely budgeted for or anticipated. Equipment and vehicles are rented and / or replaced as needed through jointly developed, annual operating agreements with the City’s other major infrastructure divisions (water, wastewater, parks, and streets). No long term SWM facility repair/replacement program currently exists. If not planned for in advance, these future expenses could create a major financial liability for the City’s future SWM Program. 0 0 $0 — 18. Water Quality Monitoring Public Works City Engineer — 0 0 $0 $0 — — WQ monitoring is not currently performed by the city. W.Q monitoring may be required by future NPDES II regulatory requirements. 0 0 $0 — 19. Legal Authorities / Ordinances (for SWM) Public Works & Community Planning Directors & City Engineer — 0 0 $0 $0 — — The City’s SW related ordinances are updated, as needed, by existing SWM Program Engineer and City Engineer. Existing ordinances will need to be reviewed/updated and new ordinances may need to be written for the City to achieve regulatory compliance with NPDES II and UIC. 0 0 $0 — 20. Legal Advise & Support (for SWM) Public Works Public Works Director — 0 0 $0 $0 — — Legal guidance for SWM is obtained from the City Attorney as needed, on an issue-specific basis. More attorney time will likely be needed in the future to develop and pass a number of new SWM ordinances, per the various regulatory requirements (NPDES, UIC, and ESA). New ordinances may also be needed for the formation of a new SWM utility and rate structure. ---PAGE BREAK--- Regulatory Compliance Analysis – Part I Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.1-10 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D1 - Ex SWM Prog-JHK.doc Table 1 (cont.) Summary of City’s Existing Stormwater Program Annual Level of Staff Effort (FTE) Annual Level of Funding Surface Water Program Elements Responsible Department Responsible Manager Assigned Staff FTE Hours Labor benefits) Expense Source(s) of Revenue Legal Authority / Ordinances Activities and Major Accomplishments Comments / Need for Enhancement (To address Local SWM Needs) 0.10 200 $9,920 Not normally required 21. Outside Services and Consultants (for SWM) Public Works Director & City Engineer Eng. Staff 0.10 200 $9,920 $0 Annual allocations from the City’s Street Department and Water/ Sewer Department — Consultants are only used on an as-needed basis for SWM. Consultants are currently in the process of updating the City’s Comprehensive Stormwater Plan ($200K). Consultant use varies from year to year depending on need. Costs also vary depending on the City’s use of grants and loans. Note: No annual budget has been included for consultants. The City will likely need to use consultants on an annual basis for CIP design and planning/implementation related to regulatory compliance. Total Annual Resources — — — 3.5 7,000 $331,284 $85,548 — — — — Total Annual Costs — — — — — $416,832 — — — — ---PAGE BREAK--- ---PAGE BREAK--- Appendix D.2 — Preliminary Compliance Strategy to Meet NPDES Stormwater Phase II Requirements ---PAGE BREAK--- ---PAGE BREAK--- Appendix D.2 — Preliminary Compliance Strategy to Meet NPDES Stormwater Phase II Requirements C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.2-1 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D2 - Prelim NPDES Assessment.doc Background Information All municipalities qualifying as a having a small municipal separate storm sewer system (MS4) were required to submit for National Pollutant Discharge Elimination System (NPDES) Phase II permit coverage by March of 2003. The City of Kennewick qualifies as a small MS4 and was required to submit for coverage, under the terms of a yet to be drafted General Permit that will be prepared and administered by the Washington State Department of Ecology. Although a draft of the permit is not available, the Federal regulation provides a significant amount of guidance on what minimum requirements of the permit will be. In order to ensure that the City of Kennewick is well positioned for compliance with the permit, it is recommended that the City assess its current programs and practices in light of current NPDES regulations and Ecology guidance. This preliminary regulatory "gap analysis" is an initial assessment of how the City’s existing programs and activities line up with the six NPDES II permit requirements. As part of the upcoming stormwater planning study, the Consultant will produce a more detailed program and budget analysis, and provide the City clear guidance on how far its current programs go toward meeting minimum compliance standards, what else needs to be done, and the projected costs of those activities. Preliminary NPDES II Regulatory Gap Analysis Below are the six minimum control measures identified in the NPDES Phase II Regulations, the must do requirements, the recommended activities and an initial assessment of where the City may be currently standing, based on our current limited understanding of the City’s existing surface water program. Minimum Control Measure #1 – Public Education and Outreach Must Do: • Distribute educational materials to the community • Conduct outreach activities regarding impacts of stormwater and steps that can be taken to reduce impacts • Establish measurable goals and report annually Recommended: • Use existing materials available • Provide information to public on how to get involved • Target groups likely to have significant water quality impacts • Consider concerns/viewpoints of minority and disadvantaged communities ---PAGE BREAK--- Appendix D.2 — Preliminary Compliance Strategy to Meet NPDES Stormwater Phase II Requirements Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.2-2 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D2 - Prelim NPDES Assessment.doc Initial Assessment – The City currently performs few of these types of public education and outreach activities, and thus, the current level of effort to adequately address all of these activities will likely need to be increased. Education programs in existing City programs, including water, wastewater, and wellhead protection, can also be used to support this effort. Minimum Control Measure #2 - Public Involvement / Participation Must Do: Comply with state, local and tribal requirements to publish notice of meetings and notice of our intent to seek coverage under the NPDES permit. Establish measurable goals and report annually. Recommended: • Stormwater Panel or Advisory Committee • Volunteer activities -monitoring, clean-ups, stenciling etc. Initial Assessment - Existing advertising efforts are generally in compliance. The City’s current level of effort adequately addresses the must do and a few of the recommended efforts. The City currently does not have a Stream Team, SWM Advisory Committee, or perform much water quality monitoring, which are all relevant to this minimum control measure. Efforts to involve the public in Watershed Planning and implementation would be applicable, and should be enhanced. Minimum Control Measure #3 - Illicit Discharge and Elimination Must Do: • Develop a map of all stormwater system outfalls that includes receiving water names • Prohibit non-stormwater discharges to system through ordinance and implement enforcement • Implement a plan to detect and address non-stormwater discharges • Inform the public of hazards associated with illegal discharges and improper waste disposal • Establish measurable goals and report annually ---PAGE BREAK--- Appendix D.2 — Preliminary Compliance Strategy to Meet NPDES Stormwater Phase II Requirements Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.2-3 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D2 - Prelim NPDES Assessment.doc Recommended: • A plan with procedures for: − Identifying priority areas − Tracing of illicit discharges − Removing or abating pollution sources Program evaluation and assessment • Promotion of public reporting of illicit discharges • Distribution of outreach materials • Storm drain stenciling Initial Assessment – The system map and the WQ complaint response program are already in place. The City’s current level of effort begins to adequately address all must do and some of the recommended efforts; however, there is some additional work that needs to be done. It is likely that the City will need to better enforce their illegal discharge ordinance. The existing Stormwater Ordinance and design standards are helpful, but enforcement measures need be taken when discharges are identified by the public or staff. The City will likely need to formalize their plan for the detection of illicit discharges and increase its efforts to enlighten the public regarding hazards of illicit discharges. It will also need to formalize procedures for identifying priority areas, tracing of illicit discharges, removal and abatement of pollution sources and program evaluation. Additional effort could also be expended on promotion of illicit discharge reporting and distribution of educational materials. Both volunteers and staff could be used to accomplish additional catch basin stenciling. Minimum Control Measure #4 - Construction Site Runoff Control Must Do: • Develop a program to reduce pollutants from construction activities that disturb ≥ 1 acre • Implement an ordinance that requires appropriate erosion and sediment control and addresses proper disposal of construction wastes • Develop and implement procedures for: − site plan review − site inspection and enforcement − public input • Establish measurable goals and report annually ---PAGE BREAK--- Appendix D.2 — Preliminary Compliance Strategy to Meet NPDES Stormwater Phase II Requirements Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.2-4 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D2 - Prelim NPDES Assessment.doc Recommended: • Procedures for individual review of pre-construction plans for development disturbing ≥ 1 acre • Procedures for site plan review, inspections, and enforcement • Provide appropriate education and training opportunities for construction site operators Initial Assessment – Assuming the City adopts the new Ecology manual for eastern Washington with the needed supporting ordinances, the City’s current level of effort should adequately address many, but not all, of the must do and recommended efforts. Compliance requires a regulatory change that reduces the threshold for site plan review to sites that disturb ≥ 1 acre or more of land. Existing ordinances related to erosion and sediment control and construction waste efforts should be reviewed and may need to be enhanced along with the threshold issue. The City will need to document site plan review, site inspection, and enforcement procedures, as well as formalizing how public input is handled during the permitting and construction processes. The City may already do pre- construction site plan reviews when needed, however, the threshold will need to be lowered to reach compliance. The City will also need to increase the effort to educate construction site operators. Minimum Control Measure #5 - Post Construction Stormwater Management for New Development and Redevelopment Must do: • Develop a program, using an ordinance or other regulatory means to address runoff from new development and re-development projects that disturb ≥ 1 acre • Implement a strategies with a combination of structural and non- structural BMPs • Ensure long-term maintenance and BMPs • Establish measurable goals and report annually Recommended: • Implement BMPs to minimize water quality impacts and maintain pre- development runoff conditions that are appropriate to local conditions • Participate in watershed planning efforts ---PAGE BREAK--- Appendix D.2 — Preliminary Compliance Strategy to Meet NPDES Stormwater Phase II Requirements Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.2-5 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D2 - Prelim NPDES Assessment.doc • Assess existing ordinances, policies, and programs that address stormwater runoff quality • Provide opportunities for public participation Initial Assessment – The City of Kennewick has addressed some the must do and recommended practices. The City may need to review and develop a new stormwater ordinance, and will need to look at thresholds to ensure that they are adequate to meet permit requirements. The City will also need to work with its Planning Department to establish requirements for non-structural solutions (zoning, setbacks, impervious surface limits, tree retention, other low impact development (LID) approaches, etc). The City’s present approach to long-term maintenance is not likely adequate to meet permit requirements, and will need to be enhanced. As use increases, there will be a need to increase the emphasis on inspection of non-structural BMPs and small sites that will be newly regulated under the program. Under the new Ecology manual for eastern Washington, the City will be implementing appropriate BMPs, reducing water quality impacts, and attempting to maintain pre-development conditions to ensure compliance. The City should initiate efforts to produce and implement effective watershed planning efforts that identity capital needs, regional opportunities, and appropriate non-structural stormwater strategies. In the future, the City will need to regularly assess existing ordinances, policies, and programs relevant to stormwater, and involve the public in so doing. Minimum Control Measure #6 - Pollution Prevention/Good Housekeeping for Municipal Operations. Must Do: • Develop and Operation and Maintenance Program to prevent or reduce pollutant runoff from county operations • Include employee training to prevent or reduce stormwater pollution from park, open space, buildings, roads and county operated stormwater systems • Establish measurable goals and report annually Recommended: • Maintenance activities and schedules and long term inspection procedures ---PAGE BREAK--- Appendix D.2 — Preliminary Compliance Strategy to Meet NPDES Stormwater Phase II Requirements Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.2-6 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D2 - Prelim NPDES Assessment.doc • Controls on the discharge of pollutants form streets, salt/sand stockpiles, parks, parking lots, waste transfer stations, etc. • Procedures for disposing of waste from the MS4 • Ensure that new flood management projects assess impacts on water quality Initial Assessment: - It is likely that an additional level of effort will be necessary to show citywide compliance with some of the must do and recommended practices contained in this minimum control measure. Streets, Wastewater, Water, Stormwater, Parks, Administration Services, and potentially other City departments that own buildings/parking lots, etc. will have to perform regular maintenance to reduce pollution from their operations and to train employees. The City's existing long-term inspection program for the stormwater system is likely not adequate, and will need to be enhanced. Additional effort may be necessary to reduce non- point pollution from stockpiles, parking lots and other city facilities like road sheds. Maintenance wastes from the portion of the MS4 maintained by the City may be adequately addressed currently, however, street sweepings and other waste streams may need to be addressed and procedures developed. Assessing water quality impacts from new flood management projects may also need to be done, on an as needed basis. The City should be considering taking a next step, over the next five years, to set a policy of instituting runoff quality enhancement features into all surface water projects to the maximum extent practicable. Administration, Management, and Reporting It should be noted that the local agency responsible for NPDES compliance will have added administrative responsibilities. The local agency will be responsible for evaluating implementing, implementing best management practices, establishing measurable goals and assessing progress toward reaching established measurable goals. The municipality will also be required to retain and manage all records required by the NPDES permitting authority for a minimum of 3 years and submit them upon request. The records must also be made available to the public. There is a requirement for submittal of progress reports for each year during the first five- year permit term. Reports are to include: • Status of compliance • Appropriateness of BMPs applied • Progress toward reaching measurable goals • Results of data collected and analyzed during the reporting period ---PAGE BREAK--- Appendix D.2 — Preliminary Compliance Strategy to Meet NPDES Stormwater Phase II Requirements Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.2-7 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D2 - Prelim NPDES Assessment.doc • Summary of activities to occur in the next reporting period • Changes in measurable goals While the City of Kennewick has accomplished a lot of work that will make compliance with the Phase II permit much easier, it is anticipated that additional efforts will be necessary to ensure full compliance with the intent of the regulations. These efforts will be quantified, in terms of staff, equipment, and costs, in the City’s upcoming Comprehensive Stormwater Planning Project. These efforts will be, compared with the City's NPDES II Permit Application, and described and prioritized according to a 3-5 year implementation schedule, as needed for the 2005 submittal of the General Permit to Ecology. ---PAGE BREAK--- ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy ---PAGE BREAK--- ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-1 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Background The City of Kennewick is subjected to a number of federal, state, regional and local stormwater-related requirements. The purpose of the regulatory compliance analysis is to review each of the stormwater regulatory requirements and present a strategy for the City of Kennewick to comply. This strategy includes identifying existing programs and activities that meet permit requirements and outlining what additional resources may be required. This regulatory “gap” analysis will allow program and budget gaps to be identified. Costs associated with filling these gaps will be included in the City’s Comprehensive Stormwater Plan. An initial assessment of the City’s compliance with the NPDES II Municipal Stormwater Permit was previously completed in June 2004. This analysis builds on that initial assessment and provides a more detailed look at a wider variety of stormwater regulations. The following stormwater regulations are included in this analysis: • The NPDES Phase II Municipal Stormwater Permit, as required by the Clean Water Act, • The Underground Injection Control (UIC) Rule, as required by the Safe Drinking Water Act, • Endangered Species Act: Section 4(d) Rule, and • The Construction Stormwater General Permit, as administered by the Department of Ecology for compliance with NPDES construction stormwater guidelines. The State of Washington is a delegated state with primacy for the CWA and SDWA. This gives the State the same rights as EPA to interpret, prescribe, and enforce the federal stormwater regulatory requirements, including the NPDES II Permit and UIC Rule. Being a delegated agency the State may add its own more restrictive requirements, in addition to those required by the Environmental Protection Agency (EPA) and when issuing NPDES permits, must ensure that state laws are met insofar as they may exceed federal laws. The Federal Wellhead Protection Program also impacts the City of Kennewick. However, the City developed its Wellhead Protection Plan in 1997 and annually funds elements of the plan to an adequate level. Additional stormwater regulatory guidelines were reviewed, but not included in this analysis because they do not affect the City of Kennewick. These additional guidelines include: • Water Quality Compliance Studies and Requirements, as required by 303(d) List of Impacted Water Bodies, Total Maximum Daily Load (TMDL) Studies, and the implementation of Load Allocation Plans/Activities, and • State Watershed Inventory Resource Act (WRIA) Studies/Plans. Formatted: Bullets and Numbering Formatted: Bullets and Numbering ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-2 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Regulatory Requirements Summary A summary of the requirements for each of the reviewed permits is included below. In many areas, the regulations have significant overlap in terms of goals, as well as activities required for compliance. In other areas one permit might go well beyond what is required in the others. Each permit also has a different level of monitoring, tracking, and reporting expectations. One common theme is the identification, tracking and attainment of specific measurable goals to assure compliance with the permit requirements. NPDES Phase II Municipal Stormwater Permit The six minimum requirements of the federal NPDES Phase II Municipal Stormwater Permit, as described by the Environmental Protection Agency in the federal register (December, 1999), include the following: NPDES #1 — Public Education and Outreach NPDES #2 — Public Involvement and Participation NPDES #3 — Illicit Discharge Detection and Elimination NPDES #4 — Construction Site Stormwater Runoff Control NPDES #5 — Post-Construction Stormwater Management for New Development and Redevelopment NPDES #6 — Pollution Prevention and Good Housekeeping for Municipal Operations These six minimum requirements also match those outlined in Ecology’s Draft of the General Phase II permit being written for Eastern Washington. The final issuance of the Eastern Washington General Permit is expected in June 2006. In addition to these six minimum pollution control measures, NPDES also requires two more significant things: compliance with (new must include NPDES permitted discharges when allocating allowable pollutant loads); and program record keeping, implementation and success monitoring, and annual reporting to the permitting agency (Ecology). The application due date for this federal permit, as administered by the State Department of Ecology, was March 10, 2003. The City of Kennewick met that requirement by submitting an Individual Permit Application to Ecology. The permit application included an implementation schedule and a list of milestones to cover the five years of permit coverage. UIC Rule The overall requirements of the revised UIC Rule are: Design, construct, and operate new UICs in compliance with Ecology’s presumptive ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-3 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc standards, or build an argument that technically demonstrates that other approaches can/should be used and are just as protective as the presumptive standards, Register all new UICs with Ecology before construction, providing supporting information about expected site conditions and pollution management activities, Locate and register all existing UICs with Ecology, providing supporting information about actual site conditions and any pollution management activities, Assess the treat posed by existing UICs to groundwater quality, identify those that present a high threat, and determine a retrofit program and schedule to eliminate the threats (retrofit activity can be structural projects or non-structural programs that reduce pollutant loading, Seek State Waste Discharge Permits for systems that are not considered “Rule Authorized” by Ecology. Decommission wells that do not meet core standards and cannot be brought up to standards using retrofit programs. These overall requirements can be further broken down into two main requirements with various subtasks. These subtasks better define UIC compliance and management program activities: Requirement #1 — Form an Underground Injection Control Program that includes the following considerations: UIC #1.1 — Locate and map all publicly owned infiltration facilities, collecting site and groundwater information as well. Document land uses draining to public drywells. Identify any discharging directly into groundwater, including seasonal high water tables. UIC #1.2 — For new UICs, comply with Ecology’s “presumptive” standards and source control requirements or develop a “demonstrative” regional risk-based strategy for the application of future stormwater infiltration systems based on soils, groundwater, drinking water wells, local pollution management programs, etc. UIC #1.3 — For existing UICs, develop a defensible technical UIC assessment protocol, assess the threat posed to groundwater quality, and identify publicly owned UICs that may create a high risk for ground water degradation by stormwater. UIC #1.4 — For existing UICs, develop a written management and/or replacement strategy (retrofit program) that will reduce pollutant loadings to groundwater by specifically focusing on the systems identified in 1.3 above. UIC #1.5 — Develop any needed UIC management training materials. Requirement #2 — Implement an Underground Injection Control Program that addresses the following requirements: UIC #2.1 — Implement adaptive annual management strategy (UIC # 1.4) for high risk existing systems. To be technically defensible, the management strategy likely must include projects, monitoring, effectiveness assessment, report preparation, enhanced O&M, source control, spill control/response, and opportunistic retrofits during reconstruction projects. UIC #2.2 — Register all publicly owned infiltration systems, including retrofit program ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-4 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc details and schedules when needed to avoid a “non-Rule Authorized” determination by Ecology. UIC #2.3 — Develop and enforce UIC construction standards (use Ecology Presumptive standards or develop Demonstrative standards). UIC #2.4 — Perform post-construction pollution management and source control for public systems, provide regular maintenance. UIC #2.5 — Provide ongoing staff training on pollution prevention and proper O&M. UIC #2.6— Conduct monitoring as needed to validate the retrofit program and allow the use of adaptive management. UIC #2.7— Provide reporting to Ecology as needed to illustrate that the retrofit program is being implemented. Note the significant amount of overlap between the Phase II NPDES Permit and activities needed to comply with the draft UIC Rule. This will be of great assistance to the City of Kennewick in developing an overall regulatory compliance strategy ESA Section 4(d) Rule The elements of the ESA relating to stormwater (taken from the Stormwater Management Proposal of the Tri-County ESA 4(d) Rule) include the following: ESA 1 — Land use decisions and regulations -Assess stormwater impacts when making land use decisions. reduce stormwater runoff, impervious surfaces, and retain native vegetation. ESA 2 — Technical Standards - Adopt standards equivalent to Ecology Manual. ESA 3 — Inspection / Enforcement ESA 4 — Maintenance Standards ESA 5 — Source Control - Adopt source control standards within Ecology Manuals ESA 6 — Illicit Discharge ESA 7 — Public Education ESA 8 — Public Involvement/Outreach ESA 9 — Governmental Coordination ESA 10 — Monitoring ESA 11 — Stormwater Planning ESA 12 — Capital Improvement Program ESA 13 — Habitat Enhancement/Protection ESA 14 — Habitat Acquisition With the exception of ESA Elements # 13 and 14 relating to habitat enhancement, protection and acquisition, the requirements of the six elements of the NPDES II Permit and the remaining 12 elements of the ESA Stormwater requirements are similar. Tri-County ESA Technical Advisory Committee, chaired by the City of Bellevue, ensured that there was consistency and continuity between NPDES II and ESA ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-5 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Construction Stormwater General Permit The requirements of the proposed Construction Stormwater General Permit (CSGP) as outlined by Ecology include the following elements for construction sites with more than one acre of soil disturbing activities: • Publish public notice of construction activities. • Comply with TMDL and 303(d) listing requirements. • Prepare a Stormwater Pollution Prevention Plan outlining BMPs and proposed monitoring activities to control erosion and sediment during construction. • Apply AKART (all known, available, and reasonable methods of prevention, control and treatment) throughout the construction area. • Implement and maintain all BMPs according to the • Keep a site log book. • Conduct regular site inspections. • Conduct turbidity and/or transparency monitoring at discharge locations based on the size of the proposed construction activity. • Keep good records and submit inspection and monitoring reports to Ecology. • Submit Notice of Termination to Ecology upon completion of the project. The regulatory requirements of the CSGP apply specifically to construction site operators disturbing one or more acres during construction activity. The permit does not require additional activities within the City’s stormwater program, though the City may elect to provide additional training and public education relating to erosion and sediment control on construction sites. For this regulatory analysis, city activities relating to education and training covered with the NPDES II requirements, specifically requirement #4 – Construction Site Stormwater Runoff Control. Additional requirements apply to jurisdictions that would like to become recognized as a “Qualified Local Program.” Such a designation would allow small site operators (those disturbing less than 5 acres) within the local jurisdiction to be covered under the general permit without an individual application. Those additional requirements include adopting an erosion and sediment control ordinance or code that is at least as strict as the CSGP. At this time, the additional requirements for Qualified Local Programs have not been included in this analysis. Regulatory Requirement Comparison For the purpose of conducting the following regulatory gap analysis, six minimum requirements of EPA’s NPDES II General Permit, have been compared with the requirements of the State’s Underground Injection Program, and the fourteen requirements of the Endangered Species Act. Areas where the regulations overlap or Formatted: Bullets and Numbering ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-6 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc where a single group of activities or programs might satisfy the requirements of multiple permits are summarized in Table 1. Table 1 Comparison of NPDES II, UIC, and ESA Requirements NPDES Phase II Requirements Corresponding UIC or ESA Requirements #1 Public Education and Outreach ESA 7 #2 Public Involvement and Participation ESA 8 #3 Illicit Discharge Detection and Elimination ESA 6 #4 Construction Site Stormwater Runoff Control #5 Post-Construction Stormwater Management for New Development and Redevelopment UIC 2.3, ESA 1, ESA 2, ESA 3, ESA 5 #6 Pollution Prevention and Good Housekeeping for Municipal Operations UIC 2.4, ESA 4 #7 Monitoring, Reporting, and Recordkeeping UIC 2.6, UIC 2.7 ESA 10, ESA 11 #8 Compliance with Additional Permit Requirements #9 Permit Application Preparation Preparation/Five-Year Implementation Schedule Table 1 shows the many areas of overlap between the regulatory compliance requirements governing stormwater activities in the City of Kennewick. In particular NPDES II requirement #5 covers many of the UIC and ESA requirements. This overlap is expected because the NPDES II permit for Eastern Washington requires that permittees adopt development standards that are consistent with the Stormwater Management Manual for Eastern Washington. The manual outlines guidelines, strategies, and BMPs that aim to help projects comply with other regulatory documents, including the UIC Rule and the ESA 4(d) Rule. The UIC and ESA criteria that do not directly correlate to one of the NPDES permit requirements include: UIC 1.1-1.4, 2.1, and 2.2 – locating and registering UICs and developing a strategy to monitor discharge, respond to spills, or retrofit high risk systems. UIC 1.5 and 2.5 – developing materials and training staff about UIC guidelines and procedures ESA 9 – developing intergovernmental agreements ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-7 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc ESA 12, 13, and 14 – identifying projects to improve stormwater management, enhance habitat, and acquire critical habitat areas Role of Stormwater Monitoring Current federal and State stormwater regulations, (i.e. primarily the NPDES II and UIC Rule) are taking a systematic, programmatic approach to the management of the non-point pollutants in urban stormwater runoff. That is, the regulatory agencies are requiring the City of Kennewick, as well as other cities and counties throughout the State, to adopt and employ various Best Management Practices (BMPs) to address the pollutants in stormwater runoff. The monitoring that has been called for in these regulations is to take the form of the annual tracking and reporting of the development and implementation of the various BMPs that are listed in the NPDES II and UIC stormwater requirements. The Department of Ecology has suggested that the agency would eventually like to move toward water quality-based NPDES II and UIC Permit requirements, but at this time they are not specifically required. A few municipal agencies have taken the initiative to start a local water quality monitoring program, ahead of any specific permit requirement. Ecology has written turbidity and/or transparency monitoring into the new draft of the Construction Stormwater General Permit. This type of water quality monitoring would apply to construction sites with more than one acre of soil disturbing activity. While this requirement could have significant impact on the construction inspection process, it is unlikely to affect municipal agencies directly. The burden for monitoring the quality of construction site runoff would likely fall on private contractors constructing municipal projects. Before Ecology requires the use of monitoring to determine the effectiveness of local stormwater programs, it is hoped that the agency will also take cost into account. The financial impacts of monitoring on a small local community are significant, and the state of knowledge concerning the effectiveness of stormwater monitoring is not well understood. Based on cost and a lack of proven effectiveness, water quality monitoring is not suggested for the City of Kennewick at this time. Method of Analysis As noted in the above discussion, there is significant overlap between the six minimum requirements of EPA’s NPDES II General Permit, the twelve requirements of the State’s Underground Injection Program, and the fourteen requirements of the Endangered Species Act. ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-8 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc A regulatory compliance “gap analysis” was performed by first comparing the City’s existing Stormwater Program to the six minimum requirements of the NPDES II Municipal Permit. The City first was given credit for its existing stormwater program activities and current levels of staffing, funding, equipment, ordinances, and technical expertise. Then, gaps between the minimum requirements and the existing stormwater program were identified. Next, the requirements of the NPDES II Permit were compared with the fourteen requirements of the Underground Injection Control Rule. The same was done between the NPDES II Permit and the fourteen requirements of the Endangered Species Act. Any additional requirements from the UIC Rule and ESA were compared against existing city programs and additional gaps were identified. After all the gaps were identified, a list of additional activities and resources needed for compliance was assembled. This list includes additional staffing, maintenance activities, financial analysis, equipment purchases, programs, ordinances, and policies needed to “fill the gaps” between the City’s existing stormwater program and regulatory requirements. The list of activities and resources needed for compliance is based on the guidance of the Model Program for Eastern Washington. The model program includes both required and recommended activities for small and large cities. Based on population, the City of Kennewick will likely need the activities for a large city (population greater than 50,000). The model program identifies annual staffing and funding levels needed to manage and implement each of the regulatory compliance activities. Because labor costs vary from city to city, this analysis focuses on the hours and full time equivalents (FTEs) needed for each of the regulatory tasks. These FTEs were converted to annual costs based on salary and benefit data specific to the City of Kennewick. For each subtask within the various permits, we took the required labor hours needed in Year 5 of the model program and subtracted the labor hours the City current spends in qualifying activities. The hours remaining represent the “labor gap” between the existing program and what is needed for full regulatory compliance. The labor gap for each task is converted to annual cost at a rate of $50 per labor hour. This represents the average hourly salary of a staff engineer at the City of Kennewick including a 46% mark-up for benefits. This analysis assumes that most of the new tasks needed for regulatory compliance will be performed by someone on the staff engineer level. While some tasks may require additional management time, those hours will likely be absorbed within the job descriptions of existing supervisors. This analysis assumes that no additional management hires will be needed to meet the regulatory compliance requirements. Some tasks also have additional costs assumed for materials as described in the detailed analysis. Material costs are particularly important for tasks such as Public Involvement and Education, where money must ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-9 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc be set aside to print and mail brochures or to purchase display materials for public events. The detailed regulatory compliance analysis is included in the attached Regulatory Requirements – Gap Analysis and Costs report. While ESA and UIC activities have been combined with NPDES requirements whenever possible, this analysis assumes that each of the NPDES requirements will be addressed with individual programs. However, the descriptions below identify potential efficiencies and opportunities to combine activities to save staff time and associated costs. Finally, an implementation schedule and funding plan was assembled to help distribute the activities and costs over the five years of the permit cycle (see Section Regulatory Compliance Gap Analysis In the following presentation, the minimum control measures of NPDES II are compared with the City’s existing programs and activities. A recommended compliance strategy, including staffing, funding, and an implementation schedule is presented. In many cases, the implementation schedule matches the schedule proposed in the City’s NPDES II permit application. Using the grouping and comparison presented in Table 1, the analysis then reviews the remaining UIC, ESA, and CSGP elements not covered by the six NPDES II requirements. Additional detail supporting this analysis is included in the attached Regulatory Requirements – Gap Analysis and Costs report. The report provided a detailed break down of all the regulatory compliance activities required and recommended in the Model Program for Eastern Washington. The activities are summarized by regulatory requirements and a five-year cost distribution and schedule is also included. NPDES Requirement #1 — Public Education and Outreach and NPDES Requirement #2 — Public Participation and Involvement Corresponding Requirements: ESA 7 – Public Education ESA 8 – Public Involvement Goals and Objectives: • To raise public knowledge and improve understanding in order to change personal actions and raise local support and funding. • To actively involve the public in the SWM program to create broad public support and ownership, take advantage of local expertise, and enhance regional watershed planning. ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-10 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Compliance Requirements: NPDES II: Distribute materials, conduct outreach activities, and define measurable goals. Solicit public input on stormwater program. ESA: Same as NPDES II. Analysis: The goals and required activities for public outreach and education are similar for each of the permits. Current Activities/BMPs In Place Locally The City’s current public education program is lacking. The City currently responds to citizen complains of flooding problems, but does not have a proactive public involvement/education (PIE) program. To achieve compliance with NPDES II, an ongoing PIE program needs to be established. The PIE program should be based on an annual plan that addresses the regulatory objectives and expectations, and annually receives stable and predictable source(s) of funding for implementation. The PIE program should cover all aspects of stormwater education, including underground disposal. In this way, the NPDES II program will also satisfy the requirements of ESA. Level of Resources for Compliance: Resources dedicated to Due to the emphasis given to both public education and involvement, in all of the regulatory documents, the City will need to dedicate resources to this area of compliance. Staff time will be needed to develop a PIE program that includes a variety of activities. Education recommendations include stormwater brochures, storm drain stenciling, classroom education, outreach to volunteer groups, and displays at public events. The City will also need to dedicate staff to solicit and compile public input on stormwater topics. To cover the activities needed for all of the regulatory guidelines at least one third of a dedicated, trained staff person’s time is warranted Annual Staffing Needs and Funding: For NPDES II 576 additional staff hours per year (0.3 FTE) plus $28,000 for printing and distribution of materials. For NPDES II 97 additional staff hours per year (0.05 FTE) and $2,400 or materials. For ESA (7 and Included in NPDES II ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-11 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Cost savings could be achieved by combining public education and public involvement activities. Holding public meetings that distribute stormwater input to the public while receiving comments on proposed programs. Schedule and Implementation: The first priority is to develop an education/outreach strategy. This strategy should be in place by the end of Year 3, so that outreach activities (including stormwater brochures, classroom education, and website creation) can begin in Year 4. Storm drain stenciling should also start by Year 4 with a target of reaching 20% of the drains in each subsequent year. Public Meetings to solicit stormwater input should start in Year 1 along with the development of a stakeholder advisory committee focused on stormwater issues. Opportunities for news releases should be identified immediately with the target of publicizing at least one story per year. NPDES Requirement #3 — Illicit Discharge Elimination Corresponding Requirements: ESA 6 – Illicit Discharge Goals and Objectives: • To eliminate untreated discharges to reduce pollutant loading to the stormwater system. Compliance Requirements: NPDES II: Map outfalls, develop ordinance(s), create a detection plan, provide inspection and enforcement, develop spill response and enforcement plans, provide staff training, educate on proper disposal, and identify and track measurable goals. ESA: Same as NPDES II. Analysis: The NPDES II and ESA goals and activities related to illicit discharge are the same. Current Activities/BMPs In Place Locally The City of Kennewick is in the process of mapping existing outfall locations and existing connections between the storm and irrigation systems. Other forms of illegal connections have not been located or mapped. The City has adopted an ordinance prohibiting illicit discharges on private property, which is further enforced through the City’s nuisance law. Through the City’s Wellhead ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-12 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Protection Plan, they have developed emergency response procedures that also cover spill response. The procedures include an Emergency Call Roster, Radio Contact Roster, Personnel List, and Employee Experience Table. Limited training, on an as-needed basis, is coordinated through the City’s Environmental Engineer. Level of Resources for Compliance: Additional resources are needed to develop an illicit discharge detection plan and to update the spill response plan to include recordkeeping and reporting requirements. Resources will then be needed to investigate and map illicit discharge locations and to work with owners to remedy the situations. Additional staff training focused on illicit discharge and spill response is needed to improve awareness. Annual Staffing Needs and Funding: For NPDES II 1,458 additional staff hours per year (0.7 FTE) plus $1,600 for materials. For ESA Included in NPDES II Cost savings could be achieved by combining screening and inspection time with current maintenance activities. Existing maintenance staff can be trained to identify and document potential illicit discharge locations. Schedule and Implementation: The City is completing the work to map existing outfalls and receiving waters. The next stop is to develop an illicit discharge detection plan over the next two years. Inspection should begin by Year 3 along with work on implementation of the spill response plan. All elements of the plan should be in place and active by the end of Year 5. NPDES Requirement #4 — Construction Site Stormwater Runoff Control Corresponding Requirements: None for UIC or ESA Goals and Objectives: • To reduce erosion and sedimentation from active construction sites. • To limit the discharge of pollutants to surface waters. ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-13 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Compliance Requirements: NPDES II: Reduce pollution from construction sites by creating and using ordinances for erosion control, proper control/disposal of construction wastes, establishment and use of temporary BMPs, and design manual adoption; provide training opportunities for developers/contractors, site plan reviewers, and field inspectors; increase routine inspection and enforcement; and receive public input on construction site runoff issues. Analysis: Many City activities related to this NPDES II requirement overlap with the guidelines in the CSGP. However, the specific requirements of the CSGP fall primarily to the construction site operator for implementation and to Ecology for review and enforcement. By implementing the activities of this NPDES II requirement, the City will move closer to becoming a Qualified Local Program. That designation would allow the City to take over review and enforcement of the CSGP for small sites (less than five acres). For the City to become a Qualified Local Program, turbidity and/or transparency monitoring requirements would need to be added to the erosion and sediment control ordinance. Such an addition is not recommended at this time. Current Activities/BMPs In Place Locally The City currently reviews site plans prior to construction. However, local ordinances do not outline erosion and sediment control measures. The City also conducts inspection of active construction sites. The City does not have an official program to receive public information relating to construction sites, although information received through informal means is passed on to site inspectors. Level of Resources for Compliance: For full compliance with this NPDES requirement, a new ordinance is needed to require erosion and sediment controls for site operators disturbing more than one acre. The ordinance must be developed to meet final NPDES II Permit criteria. Additional staff may be needed to increase site inspection and enforcement. Training is needed for both City staff and local contractors. A revised fee schedule may be established to provide resources for the increased services. Annual Staffing Needs and Funding: For NPDES II 1,996 additional staff hours per year (1.0 FTE) plus $6,000 for materials. Some of these costs may be offset by fees collected as part of construction site permitting. Additional cost savings may be achieved by combining activities with ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-14 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc those required for post construction stormwater runoff control. This could include holding joint trainings for plan reviewers and site inspectors and updating ordinances simultaneously. Schedule and Implementation: Because the City already has a construction site inspection/enforcement program, the needed compliance activities related to erosion and sediment control can be added to this program and phased in over time. Immediate changes are needed to: • Establish measurable goals • Write and adopt ordinances outlining erosion and sediment control requirements and establishing a site threshold at one acre. • Adopt the SWMM for Eastern Washington or develop locally equivalent BMPs for erosion and sediment control. • Document inspection/enforcement procedures and activities. • Establish a phone number to receive public input on construction activities. Other activities, including adding staff to enhance plan review, contractor training, and staff training/certification should be planned now and implemented over the next two to three years. NPDES Requirement #5 — Post-Construction Stormwater Management Corresponding Requirements: UIC 2.3 – Enforce Construction Standards ESA 1 – Land Use Decisions and Regulations ESA 2 – Technical Standards ESA 3 – Inspection/Enforcement ESA 5 – Source Control Goals and Objectives: • To conduct prior planning and analysis necessary to minimize pollutants in post- construction runoff control rates and quantity of runoff, maintain natural processes). Compliance Requirements: NPDES II: Establish, though a stormwater plan and ordinance, the installation and maintenance of post-construction runoff controls that are equivalent to the SWMM for Eastern Washington. Apply runoff controls to public projects. Provide BMP training for plan reviewers, inspectors, and private developers. Implement plan review, inspection, and enforcement activities. ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-15 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc UIC: Develop defensible UIC design standards using the Ecology presumptive standards. Review UIC construction plans, enforce construction standards. ESA: Adopt technical design and source control standards equivalent to those required by Ecology. Encourage development practices to reduce impervious surface and retain native vegetation. Inspect facilities during and after construction to ensure compliance with standards. Take enforcement action when necessary. Analysis: The City can reach full compliance with the NPDES, UIC, and ESA requirements by adopting the new SWMM for Eastern Washington in its entirety and incorporating additional elements from the UIC rule. However, the City should carefully review what other activities would come along with full manual adoption. It may be preferable to adopt only those portions of the new manual that would be needed to meet compliance guidelines. Current Activities/BMPs In Place Locally The City currently has design standards for new development and reviews plans for compliance with those standards. The current City standards include: • Commercial and private streets must retain and dispose the 10-year, 24-hour storm on-site. • Residential subdivisions must retain and dispose the 25-year, 24-hour storm on-site. • Where conditions allow, residential subdivisions are may release the 10-year, 24-hour natural state storm. These current standards are not as strict as the standards in the SWMM for Eastern Washington. They do not include requirements for water quality treatment and the focus is on holding all water on site, rather than mitigating to pre-development levels. The SWMM for Eastern Washington also has a focus on reducing impervious surfaces and using non-structural measures for source control on new sites. The current design standards also do not include requirements for properly locating infiltration facilities of for providing pre- treatment for UICs. The City inspects public facilities during routine maintenance activities and private facilities are inspected to ensure compliance with the approved design. Level of Resources for Compliance: Compliance will require enhanced stormwater standards, site plan review, maintenance, and source control programs. The stormwater ordinance needs revision to enhance the level of control for new development and redevelopment ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-16 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc projects. Requirements should include the core elements of the SWMM for Eastern Washington. To cover the UIC requirements, the ordinance should cover guidelines for designing and locating infiltration facilities, as well as pre- treatment standards. To cover ESA requirements, the ordinance should encourage the use of reduced impervious surface and native vegetation retention as practices in providing source control of runoff. Credit could also be given to projects that implement Low Impact Development (LID) techniques in the site design. The ordinance should also have requirements for long-term maintenance of private facilities. Increased stormwater standards will require added site plan review procedures and the necessary related training for City plan review staff and field inspectors. Current activities related to construction inspection and maintenance of public facilities should continue. Long term, documented inspection of private facilities will need to be added to ensure proper maintenance. Annual Staffing Needs and Funding: For NPDES II 654 additional staff hours per year (0.3 FTE) plus $13,500 for materials. For UIC Much of these activities can be combined with NPDES II, though an additional 150 staff hours per year (0.1 FTE) and $7,500 for materials should be dedicated to UIC. For ESA 2, 3 and Included with NPDES II. Some cost savings may be achieved by combining activities with those required for construction site stormwater runoff control. This could include holding joint trainings for plan reviewers and site inspectors and updating ordinances simultaneously. UIC activities can be combined with NPDES II compliance, provided that the ordinance updates and new BMP standards include design guidelines for drywells and other infiltration facilities. Schedule and Implementation: As with the other NPDES II requirements, full implementation should be phased in over the first five years of the NPDES II permit. Updating the stormwater ordinance is the highest priority and should be completed by the end of Year 2. Implementation of guidelines, including staff training, site plan review, and regular inspection of BMPs, should follow starting in Year 3. If the initial ordinance update does not include UIC regulations, then additional updates will ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-17 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc be needed starting in Year 4, so that all necessary standards and review/inspection procedures are in place by the end of Year 5. NPDES Requirement #6 —Pollution Prevention and Good Housekeeping for Municipal Operations Corresponding Requirements: UIC 2.4 – Perform Post Construction Management and Annual Maintenance of Public Systems ESA 4 – Maintenance Standards Goals and Objectives: • To alter municipal facilities and actions to reduce pollution, including structures, maintenance, land use practices, spill prevention, and recycling. • To expand pollution prevention and good housekeeping practices to all areas of the stormwater system, including infiltration facilities. Compliance Requirements: NPDES II: To reduce pollutants from municipal operations by inspection and maintenance of the drainage system, proper disposal of maintenance wastes, review/revision or road maintenance and construction practices, and updating the operations and maintenance manual. Compliance also includes providing long range land use planning, policies, and ordinances through flood plain and critical areas management. UIC: Perform regular inspection and maintenance of drywells and other UIC systems. Provide documented O&M procedures. ESA: Same as NPDES II Analysis: The general goal of each of these guidelines is similar. Many of the required maintenance activities are already in place, but better documentation is needed. Current Activities/BMPs In Place Locally The city has portions of an existing O&M plan that needs to be documented and enhanced, where appropriate. The existing program includes street sweeping, regular inspection and cleaning of drywells, video inspections of the sanitary and storm systems, and documentation of troublesome local flooding locations. Current equipment levels are adequate the required maintenance activities. ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-18 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Level of Resources for Compliance: The City’s current O&M plan needs to be documented. Current practices should be reviewed and enhanced as necessary. The enhanced plan will need to include new guidelines for vehicle washing and dust control. An emphasis should be placed on proper disposal of waste and thorough documentation of all maintenance activities. Staff training on updated procedures will be needed once the plan is in place. Equipment purchases will be needed as maintenance equipment ages, but current equipment levels are adequate for current activities. The O&M plan should have detailed O&M procedures related to drywells and procedure to monitor for failing systems. Maintenance related to drywells should also be thoroughly documented for reporting to Ecology as necessary. In addition, site-specific maintenance plans may be needed for municipal facilities not covered by the Industrial Stormwater General Permit. Annual Staffing Needs and Funding: For NPDES II Though existing annual expenditures exceed those outlined in the Model Program, Kennewick’s extensive system of drywells, canal connections, and climate conditions require a larger maintenance program that what was assumed for the “model community” used in developing the Model Program. The City should expect to increase the current program by 1,222 additional staff hours per year (0.6 FTE) plus $29,500 for materials. For UIC 200 additional staff hours per year (0.1 FTE) plus $10,000 for materials should be added to the program to cover additional UIC needs not addressed in the NPDES II activities. For ESA Covered with NPDES II activities. Schedule and Implementation: Many of the O&M procedures are already in place. The City should continue with their current procedures. A formal O&M plan and associated manual should be completed by the end of Year 2. The plan should include BMPs for vehicle washing, dust control, deicing, and other related activities. Years 3 through 5 should focus on modifying existing activities to meet the O&M plan. The City will also need to develop specific pollution management plans for those municipal facilities that will need industrial stormwater permits. Those plans should be completed by the end of Year 2 with permit applications submitted as required by Ecology. ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-19 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc NPDES Requirement #7 — Monitoring, Recordkeeping, and Reporting Corresponding Requirements: UIC 2.6 – Conduct monitoring UIC 2.7 – Provide regular reporting to Ecology ESA 10 – Monitoring ESA 11 – Stormwater planning Goals and Objectives: • To track stormwater management goals and activities and document their implementation and effectiveness. • To provide annual reports to Ecology as condition of the NPDES II permit and UIC rule. • To re-negotiate NPDES II permit every five years. Compliance Requirements: NPDES II: Monitor/track all NPDES II activities, keep accurate records of activities, provide annual reports to Ecology, review stormwater program and redefine/reissue permit every five years. UIC: Monitoring/tracking of activities and annual reporting. ESA: Same as NPDES II. Analysis: All three regulatory documents have similar tracking and reporting requirements. The City needs to keep accurate, updated records, track deadlines and submit to each of the regulating agencies within the required timelines. Current Activities/BMPs In Place Locally The City has completed an initial NPDES II permit application. The Environmental Engineer and O/M Manager manage the permitting process. City reports regularly to Ecology as a condition of their waste discharge permit for the wastewater treatment plant and as related to construction stormwater permits. However, no formal tracking or reporting activities are in place related to NPDES II or UIC permit requirements. Level of Resources for Compliance: The City will need to develop a regular process for tracking and reporting current SWM activities that relate to NDPES II and UIC compliance. Section 8.1 of the Model Program for Eastern Washington provides example programs and activities that can be used to demonstrate BMP effectiveness. The Model ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-20 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Program also provides an example of what should be included in the annual report. Annual Staffing Needs and Funding: For NPDES II 36 additional staff hours per year (less than 0.1 FTE). Existing staff efforts need to be focused to efficiently document NPDES II compliance activities on an annual basis. For UIC (2.6 and 2.7): 90 additional staff hours per year (less than 0.1 FTE) should be focused on UIC program monitoring and reporting. For ESA (10 and 11): Covered with NPDES II budget. Schedule and Implementation: Monitoring and reporting activities should be ongoing throughout the life of the permit. The effort is likely to require more staff time surrounding the permit application date, though many tracking activities can occur throughout the year. NPDES Requirement #8 — Compliance with Additional Permit Requirements Corresponding Requirements: None Goals and Objectives: • None at this time Compliance Requirements: NPDES II: No additional requirements have been added to the City of Kennewick’s NPDES II permit compliance activities at this time. Future requirements may be added by Ecology at a later date. Current Activities/BMPs In Place Locally N/A Level of Resources for Compliance: To be determined Annual Staffing Needs and Funding: For NPDES II None at this time. ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-21 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Schedule and Implementation: To be determined NPDES Requirement #9 — Permit Application Preparation/Five-Year Implementation Schedule Corresponding Requirements: None Goals and Objectives: • To prepare permit applications on schedule to meet Ecology’s deadlines. • To negotiate the permit with Ecology. Compliance Requirements: NPDES II: To develop and submit an initial permit application by March 2003. To evaluate the need to submit a new or revised application based on the new NPDES II general permit for Eastern Washington. The deadline for the submitting a revised application is likely to occur in spring or summer 2006. Current Activities/BMPs In Place Locally The City completed their original NPDES II permit application in March 2003. Level of Resources for Compliance: At the end of each permit cycle, staff resources will be needed to review the current program, revise the compliance plan, and resubmit the permit application. Annual Staffing Needs and Funding: For NPDES II 136 additional staff hours per year (0.1 FTE). Costs could be reduced by combining activities with the annual monitoring and reporting activities. By keeping good records on an annual basis, the permit renewal application process should be more efficient. Schedule and Implementation: Because the original permit application has already submitted, additional work and the proposed schedule will depend on Ecology’s timeline for requiring new permit applications. It is anticipated that the new application deadline will be in spring 2006. However, the City will need to consider whether they will submit a new application at that time, or maintain the original application submitted in ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-22 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc March 2003. Either way, the work associated with this task will always be focused around the permit application deadlines. UIC Requirements 1.1-1.4, 2.1 and 2.2 (not covered with NPDES II) Corresponding Requirements: UIC 1.1-1.4 – Form a UIC Program UIC 2.1 and 2.2 – Implement the UIC Program Goals and Objectives: ƒ To comply with future UIC program requirements. ƒ To protect the City’s aquifer water supplies. Compliance Requirements: UIC: Locate and register all publicly owned UICs, define land use draining to all drywells and identify high risk systems. Develop and implement a written management and/or replacement strategy that will reduce pollutant loading to groundwater by specifically focusing on high risk systems. The plan should include monitoring discharge, responding to spills, and retrofitting or decommissioning high risk systems. Analysis: While many of the UIC compliance requirements are similar to those related to NPDES II, the UIC guidelines require a more intentional strategy to decommission high risk systems and a procedure for monitoring effectiveness (and retrofit/replacement as necessary) of existing systems as they age over time. Current Activities/BMPs In Place Locally The City has mapped publicly owned infiltration facilities and has developed a well-head protection plan (WHPP). Much of the activity associated with the WHPP satisfies the initial UIC requirement to form a UIC program. This work includes identifying high-risk infiltration areas within the 3-year time of travel, documenting potential contamination sources, and performing on-going maintenance activities. Level of Resources for Compliance: The City will need to review and update the WHPP on an annual basis and develop a strategy for monitoring, retrofitting, or decommissioning high-risk facilities. Some of this effort has already been started with the development of this Comprehensive Stormwater Plan. In particular, the final report will include a map of land use relating to infiltration areas and a list of recommended actions and priorities for retrofitting or decommissioning existing systems. The City will ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-23 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc also need to use the information from the mapping of facilities to register all public infiltration facilities. Annual Staffing Needs and Funding: For developing/implementing UIC management plan not covered by NPDES II: 1,020 additional staff hours per year (0.5 FTE) and $102,000 Some cost savings may be achieved by combining activities with other NPDES II requirements. However, care should be taken to make sure that the City’s stormwater management program has the needed focus on UIC elements. This is particularly important in the City of Kennewick, where the extensive drywell system forms the backbone of the City’s stormwater system. Schedule and Implementation: Many of the activities for UIC compliance are already underway. The City should continue with current activities to develop a UIC program that addresses all of the regulatory requirements. By Year 3, the focus should shift to implementing that program, including implementing the retrofit strategy and conducting the necessary staff training. UIC Requirements 1.5 and 2.5 (not covered with NPDES II) Corresponding Requirements: UIC 1.5 and 2.5 – Develop materials and Train Staff about UIC guidelines Goals and Objectives: ƒ Educate staff on UIC compliance. ƒ Provide training and materials needed to implement the UIC management plan. Compliance Requirements: UIC: Train staff about UIC guidelines, detection of high risk systems, retrofit/decommissioning methods, and O&M procedures, Analysis: UIC training can likely be combined with NPDES training activities, though UIC related trainings should be documented separately for submittal in annual reports to Ecology. Current Activities/BMPs In Place Locally The City provides training on an as-needed basis. Specific activities include tabletop exercises and meetings with the Washington State Military Department ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-24 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc to develop incident command center training. However, training does not currently focus on UIC requirements and activities. Level of Resources for Compliance: The city will need to develop training opportunities to educate staff about the guidelines of the UIC rule. Follow-up sessions should then focus on procedures for detecting high risk system and guidelines for retrofitting or decommissioning those systems. As with NPDES II requirements, additional training on updated O&M procedures should be included for the appropriate staff. Annual Staffing Needs and Funding: UIC training activities not covered by NPDES II: 70 additional staff hours per year (less than 0.1 FTE) and $3,500 for materials. Schedule and Implementation: Training sessions should be developed and offered as new elements of the UIC program are put in place. To maximize staff time, training sessions should incorporate elements related to both UIC and NPDES II compliance activities. ESA Requirements 13 and 14 (not covered with NPDES II) Corresponding Requirements: ESA 13 – Habitat Enhancement/Rehabilitation ESA 14 – Habitat Acquisition Goals and Objectives: • Address stormwater related requirements of the ESA 4(d) rule not already covered by the NPDES II activities. Compliance Requirements: ESA: Look for opportunities to enhance or restore habitat to protect endangered species. Where possible, acquire land or dedicate areas for long-term protection. Analysis: While 12 of the 14 ESA compliance requirements are covered by the NPDES II program, some activities specific to habitat enhancement and acquisition may need their own programs or activities. Current Activities/BMPs in Place Locally The City does not actively participate in habitat enhancement or acquisition activities outside the work of WRIA 31. Due to existing drainage features (existing levees, few natural channels), the City has few opportunities for habitat enhancement. ---PAGE BREAK--- Appendix D.3 — Gap Analysis and Compliance Strategy Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n D.3-25 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3a - Reg Compliance.doc Level of Resources for Compliance: Due to the limited opportunities for habitat enhancement or acquisition, it is not anticipated that these ESA requirements will affect the City’s stormwater funding or activities. The City will want to remain active with WRIA 31 to understand projects and proposed activities in the surrounding areas. However, no additional resources are recommended at this time. Annual Staffing Needs and Funding: For ESA activities not Covered by NPDES II: None at this time. Schedule and Implementation: Not applicable Regulatory Compliance Gap Analysis Summary This concludes the regulatory compliance gap analysis for the City of Kennewick. The attached Regulatory Requirements – Gap Analysis and Costs report includes a detailed breakdown of each of the compliance activities required and recommended in the Model Program for Eastern Washington. The report also includes a two-page summary that outlines the required additional staffing time and associated costs to achieve full compliance with NPDES II, UIC, and ESA guidelines. A five year implementation schedule and a breakdown of costs over the initial five years of the permit are included in separate sections of the Comprehensive Stormwater Plan. The regulatory compliance gap analysis shows that, by the end of Year 5, the City will need to add 3.2 FTE at an additional annual cost of $411,790 to meet full NPDES compliance. An additional 0.8 FTE and $153,000 will be needed for full UIC compliance. The analysis also recommends that additional funds ($35,000) be set aside to equipment maintenance and replacement. Because these staffing and funding requirements recommend levels needed by Year 5 of the program, it is recommended that the City look to slowly add staff, perhaps at a rate of one every two years. Some cost savings, and perhaps FTE reduction, can be achieved by combining tasks and shifting staff loads to maximize efficiency. The City may find that maintenance responsibilities are reduced as CIP projects address common problem areas. Hours currently spent on maintaining problem areas can then be shifted to another area, such as illicit discharge inspection or spill response. Looking for these efficiencies and being flexible in the implementation of new ideas and activities will allow the City to adapt and modify the surface water program to best meet the needs of the community. ---PAGE BREAK--- ---PAGE BREAK--- Regulatory Requirements - Gap Analysis and Costs Revised: November 3, 2005 Estimate of Regional Stormwater Management Costs City of Kennewick STORMWATER MANAGEMENT PLANNING PROJECT City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 1 otak ---PAGE BREAK--- New Annual Costs1 Program Elements/Regulatory Requirements Endangered Species Act (ESA) CITY OF KENNEWICK COMPREHENSIVE STORMWATER PLAN Regulatory Requirements - Gap Analysis and Costs 4 Watershed Planning $0 2 Underground Injection Control (UIC) Program 1 Element # Total: $411,790 NPDES II SW Municipal Permit 6 Equipment & Services $35,000 $153,000 $0 Water Quality: 303(d) Listed Water and TMDL Plans 5 Note: This detailed Gap Analysis is intended to provide an overall estimate of the additional cost to achieve compliance with stormwater laws and meet local needs. The program manager should plan on adjusting revenue needs as experience is gained during implementation of required activities. Unlike the CIP cost estimates, no planning level contingency factor has been used for the programmatic costs. Therefore, individual activity costs may increase or decrease depending on implementation factors. UIC compliance costs are low because of overlaps with NPDES activities. $0 3 2See Section 7 of Comprehensive Stormwater Management Plan for CIP Costs Capital Improvements2 1Start-up and one-time program development or planning costs have been annualized over the first five years. On-going programmatic costs are for fully implemented programs. After $599,790 $0 7 City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 2 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 Optional BMP 1.1A: Conduct self analysis of existing SWM Program, identify local compliance needs, costs, space, staffing, equipment, and funding needs. (No costs included in Model Program) Self analysis is currently in progress. (Initial analysis will be documented in the City of Kennewick Comprehensive Stormwater Plan.) 100% Completed self analysis will be documented in the Final City of Kennewick Comprehensive Stormwater Plan. To be completed in Summer, 2005. — — Existing Funding (Ex F) Optional BMP 1.1B: Develop local SWM Action Plan/Schedule. (No costs included in Model Program) Development of an action plan will be implemented as part of the City's SWM Comp. Plan. 100% Action Plan/Schedule shall be provided in the Final City of Kennewick Comprehensive Stormwater Plan. (Spring, 2006) — — Ex F Optional BMP 1.1C: Adopt needed interlocal agreements. (No costs included in Model Program) City has expressed an interest in establishing some interlocal agreements. 10% City will consider potential interlocal agreements, as identified in the City of Kennewick Comprehensive Stormwater Plan, Summer 2005. — — Ex F Optional BMP 1.1D: Create local funding. Measurable Goal: Bby the beginning of Permit Year 1, create adequate funding mechanism for staff, equipment, and legal authorities needed for implementation of regulatory compliance activities. (No costs included in Model Program) 368 $32,000 City received a loan from the State to pay for the Comp. Plan. The existing stormwater program is funded by allocations from the Street Department and the Water/Sewer Department. CIP projects are funded by the 0.5% sales tax. 50% (If SWM utility needs to be formed) City is identifiying new funding options and implementation strategies part of the City of Kennewick Comprehensive Stormwater Plan. Total of 1600 hours and $80,000 in first year divided by 5 to get annual average. In reality this effort will likely be condensed into two years with the same total cost. 184 $16,000 Ex F 1.1 Sub-Total: Start-up Activities (One time cost.) 368 $32,000 184 $16,000 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) *1 Activities required by regulation or optional activities recommended by the Model Municipal Stormwater Program for Eastern Washington , September 2003 (Model Program). *2 Information provided in the Model Program - Model Program cost estimates were based on assumptions that may not always be true for Kennewick, so should be viewed as rough guidance only. *3 Information provided by the City of Kennewick *4 Annual labor hours and costs are the same as the Model Program, except where noted. *5 Existing Funding will be initially used to meet regulatory compliance needs. However, a new SWM utility may be needed after years 1-2. NPDES II SW Permit Minimum Measure #1.1 Start-up Activities Goal: Perform initial permit start-up and planning activities. (NOI Develop and implement a storm water education and outreach strategy by the end of year 3. *Note: Start-up and one-time program development or planning costs have been annualized over the first five years. On-going programmatic costs are for fully implemented programs. After five years, the annual budget should be reviewed and the rates adjusted up or down as needed. Capital costs (CIP) have been annualized over ten years with the average annual CIP cost added to the estimated annual program costs. Stormwater Program Element #1 - NPDES II SW Municipal Permit Required and Optional BMP per the Model Municipal Stormwater Program for Eastern Washington , September 2003 City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 3 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Required Required BMP 1.2A: Education/Outreach Strategy Develop and implement a stormwater education and outreach strategy that examines target audiences and potential stormwater hazards. Measurable Goal: By the end of Permit Year 3, develop a stormwater education and outreach strategy for implementation during the remainder of the permit term. (One time cost.) 8 $600 New initiative needed. 0% Likely Y Additonal 12 hours and $1,160 needed in Year I to plan select, fund and implement 5 PEI activities. 1) Use the Model Program's Appendix 2C to help identify, target audiences that have the greatest potential to impact the storm drainage system. 2) Identify stormwater problems and potential solutions. 3) Develop a distribution plan for educational materials. 8 $600 Ex F Required BMP 1.2B: Stormwater Brochure Develop and distribute a brochure to inform the general public about stormwater issues. Measurable Goal: By the end of Permit Year 5, distribute the brochure to 90% of the residences and businesses within the storm drain system. 114 $15,810 New initiative needed. City noted that locals are encouraged to drain their pools into their yards, opposed to into the storm drain system. However, City did not say how this information was provided to the public. City also said that overwatering would be a good education topic. Overwatering causes the drywells to silt in faster and require more frequent maintenance. 0% Likely Y Develop brochure for the general public. Distribute with City utility bill to save on postage. Example brochures are available: http://www.sanjuancapistrano.org/media/PolPrev_Storm Water.pdf, http://www.thinkbluesd.org/brochures/ThinkBlue_Broc hure.pdf 114 $15,810 Ex F Optional*6 BMP 1.2C: Targeted Stormwater Brochures Develop and distribute stormwater brochures to targeted audiences. Measurable Goal: By the end of Permit Year 5, distribute targeted brochures according to strategy in 1.2A. (Large City requirement.) 114 $14,980 New initiative needed. 0% Likely Y Develop and distribute brochure to a target audience identified under BMP 1.2A. Example brochures targeting automobile repair shops, the construction industry and other industries are available at: http://www.ci.phoenix.az.us/STREETS/bmps.html 114 $14,980 Ex F Optional*6 BMP 1.2D: Storm Drain Stenciling Plan and conduct storm drain stenciling. Measurable Goal: Beginning in Permit Year 3, stencil 20% of all public storm drain inlets each Permit Year. 204 $17,160 New initiative needed. 0% Likely Y Order stencils from the Washington Department of Ecology at 1-800-RECYCLE, or from Earthwater Stencils, Ltd.'s at http://www.earthwater-stencils.com/index.htm. Labor for stenciling can be provided by municipal employees or volunteers. 204 $17,160 Ex F Optional*6 BMP1.2E: Classroom Education Contact school districts to discuss opportunities to integrate water quality educational materials into the classroom; provide materials as requested. Measurable Goal: By the end of Permit Year 5, contact all school districts within the storm drain system. (Large City requirement.) 56 $4,400 New initiative needed. 0% L Y Contact school districts within the City's storm drain system and offer to distribute water quality educational materials. Example programs are available: http://ecy.wa.gov/news/ee/curricul.html, http://www.cityofboise.org/public_works/education/, and http://epa.gov/ogwdw000/kids/wsb/index.html 56 $4,400 Ex F NPDES II SW Permit Minimum Measure #1.2 Public Education & Involvement Goal: Raise public knowledge and improve understanding to change personal actions, raise local funding and support. (NOI Develop and implement a storm water education and outreach strategy by the end of year 3. City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 4 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Optional*6 BMP 1.2F: Volunteer Groups Contact volunteer organizations to discuss opportunities to integrate stormwater into existing education projects (optional). Measurable Goal: By the end of Permit Year 5, contact at least 5 volunteer organizations. (No cost information in Model Program.) ? ? New initiative needed. — ? ? Research and document volunteer organizations within the storm drainage system (this may have already been done during BMP 1.2A). Contact volunteer organizations to discuss opportunities to involve them in stormwater related activities (stenciling for example). Document involvement opportunities. 0 $0 — Optional*6 BMP 1.2G: Speakers Bureau Develop and promote a stormwater speakers bureau. Measurable Goal: By the end of Permit Year 4, develop a speakers bureau. Make 3 presentations each year. (No cost included in Model Program.) ? ? New initiative needed? 0% ? ? Recruit representatives from target audiences (identified during BMP 1.2A). Develop education materials on stormwater management for representatives to present back to their organization. An example of how to develop a speakers bureau is provided at: http://www.greenwoodvillage.com/cityman/speakers.htm l 0 $0 Ex F Optional*6 BMP 1.2H: Public Announcements Broadcast stormwater public service announcements (PSAs) through the media. Measurable Goal: By the end of Permit Year 5, create a stormwater PSA and run this PSA so the population receives the information an average of 3 times per year. (No costs included in Model Program.) ? ? New initiative needed? 0% ? ? Design a PSA for mass media . The Washington State Department of Ecology Water Quality Consortium (http://www.ecy.wa.gov/programs/wq/psters/) provides a series of newspaper and television advertisements for local governments. Run the PSA at a frequency that ensures target audiences will be exposed to the message. 0 $0 Ex F Optional*6 BMP 1.2I: Stormwater Display Display a stormwater exhibit at various community locations and events. Measurable Goal: By the end of Permit Year 5, develop a stormwater display, and use this display 4 times per year. (No costs included in Model Program.) ? ? New initiative needed? 0% ? ? Design a stormwater Display and use the information obtained in the education and outreach strategy (BMP 2A) to identify the most effective places and/or events to set- up the display. Attend at least one event per year. 0 $0 Ex F Optional*6 BMP 1.2J: Stormwater Web Site Create a stormwater website containing educational information. Measurable Goal: By the end of Permit Year 5, complete a stormwater web site; update 80 $5,640 New initiative needed. 0% L Y Create a stormwater website that contains educational material. Include the website's address on other forms of public outreach (such as brochures and displays) to ensure the community is aware of where to find additional stormwater information. 80 $5,640 Ex F 1.2 Sub-Total: Public Education & Involvement 576 $58,590 576 $58,590 *6 Large Communities must select 5 of these activities. City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 5 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Required BMP 1.3A: Public Review/Public Meetings Hold public meetings and solicit public review of the stormwater management plan. Measurable Goal: During Permit Year 1, hold two public meetings and publish two public notices. 82 $6,128 New initiative needed. 0% Likely Y 1) Determine an appropriate meeting format, use the Model Program Appendix 3A for assistance. 2) Use the education and outreach strategy identified in BMP 1.2A to announce the meeting. 3) Conduct public meeting, allowing a sufficient comment period and distribute public comment forms. 4) Perform follow-up activities, and make follow-up information available to participants. 82 $6,130 Ex F Optional*7 BMP 1.3B: News Releases Develop a news release for a feature story. Measurable Goal: Starting in Permit Year 2, distribute one (per year) news release story on jurisdictions stormwater program to local papers. 15 $1,136 New initiative needed. 0% Likely Y Create an overview of the new stormwater program activities that will be conducted and how the public can obtain more information. Print overview in the local news paper. 15 $1,135 Ex F Optional*7 BMP 1.3C: Stakeholder Advisory Panel Hold and solicit input from a stakeholder advisory panel (optional). Measurable Goal: By the end of Permit Year 1, organize and convene a stakeholder advisory panel; hold meetings quarterly thereafter. (Not included in model program.) ? ? New initiative needed. 0% Likely Y Create a stormwater advisory panel comprised of stakeholders identified in BMP 1.2A. Solicit advise from the panel and use the opportunity to develop support for the local stormwater program. — — Ex F Optional*7 BMP 1.3D: Respond to calls from the Public (No description or goals in Model Program.) Have a staff member assigned to handle calls from the public that are generated as a result of BMP 1.4 B & C.*8 200 $8,170 City receives calls related to flooding issues. Calls are recorded. Kennewick has a rating system for prioritizing drainage complaints. Locations are mapped. 100% Likely N Document calls from the public. Document action taken and follow-up (if applicable). 0.0 $0 Ex F 1.3 Sub-Total: Public Involvement/Participation 297 $15,434 97 $7,265 Required BMP 1.4A: Create Map Create a storm sewer system map showing all known outfalls to receiving waters. Conduct field surveys to ID unknown outfalls on priority waters Measurable Goal: Create map and correlated database 80 $6,000 Already developed by City; 75% complete. Otak has a copy of the CID outfall map. Otak does not have a copy of the KID outfall map. 75% Likely Y Add KID outfalls to the map. 20 $1,500 Ex F NPDES II SW Permit Minimum Measure #1.3 Public Involvement/Participation Goal: To actively involve public in SWM Program to create broad public support and ownership, take advantage of local expertise, and enhance regional watershed planning. (NOI Implement a public involvement/participation program by the end of Year 1. *7 Large communities must select at least 2 of these activities. *8 City's existing program meets this need. Hours and cost estimate in Model Program is too high for the City of Kennewick. NPDES II SW Permit Minimum Measure #1.4 Illicit Discharge Elimination Goal: To eliminate untreated discharges and reduce total pollutant loading. (NOI #3.a. Create a storm sewer map showing all known drain outfalls to receiving waters. #3.b. Develop and enforce an ordinance prohibiting illicit discharges and illegal dumping and outhorizing enforcement actions including on private property. #3.c. Develop an illicit discharge detection plan. #3.d. Visually inspect all known outfalls during dry weather. #3.e. Develop and implement a spill response plan. #3.f. Develop and implement an enforcement plan to ensure compliane with local ordinanaces. #3.g. Provide training opportunities for staff on proper BMPs for spills and illicit discharges. City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 6 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Required BMP 1.4B: Ordinance Develop and enforce ordinance prohibiting illicit discharges and illegal dumping on private property. Measurable Goal: By the end of Permit Year 2, adopt ordinance that prohibits illicit discharges to the storm drain system. 40 $2,000 There is a City ordinance prohibiting illicit discharges on private property (KMC 14.22.050 and 14.22030). The ordinance is enforced by nuisance law and code enforcement (KMC 9.48.010). 50% Likely Y Likely will need to update ordinance to address specific NPDES II requirements. Assume ordinances are addressed as part of the SWMP development. 0 $0 N/A Required BMP 1.4C: Illicit Discharge Plan Develop an illicit discharge detection plan. Measurable Goal: During Permit Years 1-2, develop a plan to detect illicit discharges. 45 $3,600 Ten storm sewer and irrigation canal interfaces are documented and mapped in the Comp Plan, therefore, some form of detection is currently in place. However, a new initiative is needed to document the plan. 50% Likely Y Need a plan for: 1) Identifying priority areas for assessment, 2) field assessing areas., 3) characterizing discharges (characterization methods are not limited to, odor, turbidity, floatable matter, abnormal vegetation, damage to the outfall, pH, and/or laboratory analysis), 4) tracing the discharge to its source, 5) notifying the appropriate authorities and property owners and ensuring enforcement. 45 $3,600 Ex F Required BMP 1.4D: Screen Outfalls Visually inspect for illicit discharges during dry weather at all known outfalls (mapped in 1.4A). Measurable Goal: During Permit Years 3-5, visually inspect 33% of all known outfalls per year. 1270 $119,400 New initiative needed. 0% Likely Y Inspect outfalls mapped in BMP 1.4A according to the plan documented in BMP 1.4C. Costs in Model Program are too high for City of Kennewick where few problems are expected, and only a few outfalls exist. Inspection can be performed by properely trained maintenance crews. 635 $30,000 Ex F Required BMP1.4E: Spill Response Plan Develop and implement a spill response plan. Measurable Goal: During Permit Years 3-5, develop a spill response plan that includes coordination with Ecology's Spill Response Team. 35 $2,880 The City's Emergency Response Procedures (including spills), Emergency Call Roster, Radio Contact Roster, Personnel List and Employee Experience Table are all included in Appendices B and C of the Wellhead Protection Plan. 75% Likely Y Update the spill response plan to include information on Ecology's Emergency Spill Response Program and spill reporting numbers (see page 4-13 of the Model Program). The spill response plan should also include record keeping and reporting requirements so that each spill, response, and outcome can be tracked. 10 $1,000 Ex F Plus Fees and Fines Required BMP 1.4F: Enforcement Plan Develop and implement an enforcement plan to ensure compliance with local ordinances. Measurable Goal: During Permit Years 3-5, develop an enforcement plan. 696 $47,760 Legal action is the City's current enforcement plan. KMC 9.48.010 lists nuisance activities as unlawful misdemeanors. KMC 14.28.050 uses a lien as stormwater enforcement. Most ordinances are written with a section on enforcement. Most enforcement performed by maintenace crews with follow up from engineering staff. 25% Likely Y Need a written plan and active program. Annual labor needed for enforcement will vary from year to year. Costs in Model Program are likely too high for the City of Kennewickwhere few problems are expected, and only a few outfalls exist.. However, enforcement costs can add- up quickly if repeated contact , testing, and legal action is required. 696 $34,800 Ex F Plus Fees and Fines Required BMP 1.4G: Training Provide training to educate staff on BMPs for spills and illicit discharges. Measurable Goal: By the end of Permit Year 5, train relevant staff. Train annually thereafter. 52 $3,600 Training is coordinated through City's Environmental Engineer, on an as needed basis. 0% as needed Likely Y Provide training to field maintenance crews, illicit discharge inspectors, and spill responders on the proper BMPs to use for spills and illicit discharges. Training should include how to identify illicit discharges, who to call for spills, etc. Can be combined with other reqiured training topics. 52 $3,600 Ex F Plus Fees and Fines 1.4 Sub-Total: Illicit Discharge Elimination 2,218 $185,240 1,458 $74,500 City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 7 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Required BMP 1.5A: Ordinance For permits issued by the City to construction operators disturbing 1 acre or more, require through ordinance that erosion and sediment controls must be in compliance with the Stormwater Management Manual for Eastern Washington, or equivalent. Measurable Goal: By the end of Permit Year 2, adopt ordinance(s). 40 $2,000 New initiative needed. City is hoping the creation of the new ordinances will be addressed as part of the Kennewick Stormwater Management Plan. 0% Likely Y City must develop the ordinance and ensure it meets final NPDES II Permit criteria. An example enforcement plan is described in Ch. 4, Sec. 4.3.5 of the Model Program. One enforcement plan can be used to address inadequate construction E&S controls, and post construction controls. 40 $2,000 ExF Required BMP 1.5B: Training Provide training to educate plan reviewers and field inspectors in erosion and sediment control BMPs. Measurable Goal: By the end of Permit Year 5, train reviewers and inspectors. Train annually thereafter. 32 $2,240 New initiative needed. 0% Likely Y Training can be developed in-house, or course information is available on-line from the International Erosion Control Association , the Associated General Contractors of Washington , or the Engineering Professional Programs at the University of Washington. 32 $2,240 ExF Required BMP 1.5C: Review site plans Review site plans disturbing 1 acre or more prior to construction to ensure compliance with local ordinances. Measurable Goal: By the end of Permit Year 5, review all site plans subject to the local ordinance. 1152 $87,040 City reviews site plans prior to construction to ensure compliance with local ordinances. No construction erosion and sediment control requirements. 50% N N Need to add requirement for construction BMPs for runoff. Also may want to allow Erosivity Waivers. Additional review time needed to review and verify compliance with new ordinance. Permit fees may be used to offset costs. 864 $43,520 ExF plus Permit Fees Required BMP 1.5D: Receive info from public Create and publish a system to receive public input on construction site runoff issues; pass information to field inspectors. Measurable Goal: By the end of Permit Year 5, publish a phone number, or equivalent system, for receiving public input. (Costs in Model Program are too high for City of Kennewick's needs.) 1524 $76,200 City said they do not have a formal system for receiving public information on construction site runoff issues, but they do respond to drainge complaints and that information from the public is passed on to field inspectors. 50% Likely N List a phone number for "construction-pollution related complaints" in the local government pages, on brochures, or on a sign at the construction site and on the web site, if available. Direct the phone number to an appropriate staff person. Keep written logs of complaints, and report complaints to the field inspectors. Follow up when necessasary. 762 $38,100 ExF Required BMP 1.5E: Inspect sites Inspect all construction sites during construction that are regulated by the ordinance adopted in BMP 1.5A. Measurable Goal: Inspect all construction sites meeting one-acre threshold criteria, at least once during construction. 1056 $69,700 City inspects all sites. 75% N N New ordinance requiring construction stormwater BMPs and specific inspection requirements of the NPDES II Permit will add additional inspection work. Permit fees may be used to offset costs. 264 $17,425 Permit Fees Required BMP 1.5F: Training for operators Provide information on local BMP training available to construction operators. Measurable Goal: By the end of Permit Year 5, provide training information to local construction operators, upon request. 34 $2,800 New initiative needed. 0% Likely Y Provide a handout listing available training resources for construction operators at the pre-construction meeting, or upon request. The training described in Section 5.3.2 of the Model Program also applies to local construction operators. 34 $2,800 ExF NPDES II SW Permit Minimum Measure #1.5 Construction Site Stormwater Runoff Control Goal: To reduce erosion and sedimentation from active construction sites. (NOI#4): #4.a. Adopt an ordinance for erosion and sediment controls for operators disturbing one acre or more. #4.b. Provide training opportunities for plan reviewers and field imspectors inerosion and sediment control. #4.c. For all construcitn sites greater than one disturbed acre, review site plans to ensure that erosion and sediment controls and post-construction controls are included and are in accordance with local ordinances. #4.d. Publish a phone number or equivalent system, to receive public input on construction site runoff issues. #4.e. Inspect all construction sites greater than one disturbed acre during the construction period that are regulated local ordinance adopted in BMP 4(a). #4.f. Provide information on erosion and sediment control training opportunities to construction operators. City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 8 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) 1.5 Sub-Total: Construction Site Stormwater Runoff Control 3,838 $239,980 1996 $106,085 Required BMP 1.6A: Ordinance For permits issued by the City to construction operators disturbing 1 acre or more, require installation and maintenance of post-construction runoff controls equivalent to the SWMM for Eastern Washington. Measurable Goal: By the end of Permit Year 2, adopt ordinance. 40 $2,000 Commercial sites and private streets are designed to retain and dispose the 10-year 24-hour storm on-site. Residential sub-divisions are designed to retain and dispose a 25-year 24-hour developed state storm. New initiative needed to address other NPDES II requirements. Coordinate with ordinance written for BMP 1.5A. 0% Likely Y Need to update city codes or prepare new ordinance that includes the core elements in the E. WA SWMM (pre- treatment, etc.) and meets specific NPDES II permit requirements. Also need to ensure long term maintenance of private facilities. Assume ordinance is developed as part of preparing the SWMP. See example ordinances in Appendices 6A and 6B of the Model Program, and language of the NPDES II permit. 0 $0 ExF Optional BMP 1.6B: Post-Construction Plan Develop a plan to address post-construction stormwater runoff. Measurable Goal: By the end of Permit Year 5, develop and adopt a plan. (One time cost.) 50 $4,000 Kennewick already does some stormwater development review, however it may be necessary to have a well thought out plan for how to address new and controversial requirements (such as private site access). 50% N Y Develop a post-construction program plan that identifies requirements and spells out how they will be addressed. 10 $1,000 ExF Required BMP 1.6C: Training Provide BMP training to educate construction plan reviewers and field inspectors about post-construction runoff controls and BMP maintenance. Measurable Goal: By the end of Permit Year 5, hire and train plan reviewers and inspectors; retrain annually thereafter. 44 $3,080 New initiative needed. 0% Likely Y Need to develop and document a training program for plan reviewers and site inspectors. Potential sources for training information include the Center for Watershed Protection (http://www.cwp.org) or the Nonpoint Education for Municipal Officials (http://nemo.uconn.edu/index.htm) MRSC Municipal Research 44 $3,080 ExF Required BMP 1.6D: Review site plans Review site plans per the plan developed in BMP 1.6B prior to construction to ensure compliance. Measurable Goal: By the end of Permit Year 5, review all site plans subject to the local ordinance. 1152 $87,640 City currently reviews plans, and post construction runoff compliance is already a City requirement. However the need for reviewers to ensure treatment, source controls, maintenace, and long term access will be more work. 75% N N Plan review effort will likely increse and stormwater review will become formalized. This task could be integrated with BMP 1.5C, and some labor/cost reduction may be realized. Note similarities to 1.5C Construction Site Plan Review. 288 $21,910 ExF Required BMP 1.6E: Inspect BMPs Inspect post-construction BMPs per the plan developed in BMP 1.6B. Measurable Goal: Inspect structural post-construction BMPs per the frequency developed by the local jurisdiction as required to protect water quality. 312 $20,160 City does inspect stormwater infrastructure during construction, however NPDES II will likely add inspection requirements, increasing the workload City does not inspect private facilities over the long term to ensure proper O&M. 25% Likely N Enhance current inspection work duing construction. Develop a post-construction inspection program to inspect all installed BMPs for proper long term O&M, including procedures, schedules, inspection forms. Identify maintenance requirements for private property owners. Some costs could be recovered by incorporation into the fee structure of the development permit. 312 $20,160 ExF 1.6 Sub-Total: Post-Construction Stormwater Management 1,598 $116,880 654 $46,150 NPDES II SW Permit Minimum Measure #1.6 Post-Construction Stormwater Management Goal: To conduct prior planning analysis necessary to minimize pollutants in post-construction runoff control rates and quantity of runoff, maintain natural processes). (NOI #5.a. Adopt an ordinance requiring post development runoff controls by end of year 2. #5.b. Develop and implemetn a plan to address post-construction runoff controls during the plan review, construction inspection and post-construction maintenance process by the end of year 5. City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 9 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Required BMP 1.7A: Develop O&M Plan Develop a municipal good houskeeping and O&M Plan that addresses the activities below. Measurable Goal: During Permit Year 3, complete development of an O&M Plan and implement for the rest of the permit term. 80 $8,000 The City*4 has portions of an O&M Plan. (The SWM Comp Plan documents some information on existing municipal operations.) 50% Likely N Document in the O&M Plan how the existing maintenance plan needs to change to address, where appropriate, BMPs 1.7B-1.7I in accordance with the Stormwater Manual for Eastern Washington. Provide staff training on the updated O&M Plan. (City to provide updated cost info for 1.7A - 1.7G.) 40 $4,000 ExF Required BMP 1.7B: Park/Open Space BMPs Per the O&M Plan, implement park and open space O&M practices. Measurable Goal: By the end of Permit Year 5, implement all pollution prevention/good housekeeping practices for park and open space maintenance. 384 $26,000 The City's current open space O&M practices are not defined in a written plan. 50% Likely N Verify that current open space O&M practices include all that is documented in BMP 1.7A. May need to secure additional annual Park funding to implement and comply. 192 $13,000 ExF Required BMP 1.7C: Vehicle Fleet and Equipment Storage, Maintenance and Washing BMPs Per the O&M plan, implement pollution prevention/good housekeeping practices for publicly-owned vehicle and equipment washing storage, maitenance, and washing. Measurable Goal: By the end of Permit Year 5, fully implement fleet and equipment BMPs. 384 $26,000 New initiative needed. 0% Likely N Conduct vehicle/equipment repair, maintenance and cleaning using appropriate WQ BMPs and waste material disposal. 384 $26,000 ExF Required BMP 1.7D: Dust Control BMPs Per the O&M plan, implement WQ BMPs during dust control practices on public projects. Measurable Goal: By the end of Permit Year 5, implement required dust control BMPs. 384 $26,000 New initiative needed. (Dust control is monitored by the Benton County Clean Air Authority.) 0% Likely N Review any dust control practices that the City has, and implement WQ BMPs as appropriate. Make sure the City's dust control BMPs include proper disposal of material (sweepings), and record keeping. 384 $26,000 ExF Required BMP 1.7E: Storm System Maintenance Per the O&M plan, implement catch basin cleaning and system O&M. Measurable Goal: By the end of Permit Year 5, regularly inspect and maintain, as needed, catch basins and other stormwater system facilities. 384 $26,000 Catch basins and drywells are cleaned regularly. GIS inventory information is collected on a lap top computer for documentation. 100% Likely (Existing Funds from City Road Fund) N Current practicies are adequate. 0 $0 ExF Required BMP 1.7F: Open Channel/Structural BMPs Per the O&M plan, implement structural O&M practices. Measurable Goal: By the end of Permit Year 5, regularly inspect structural stormwater controls. 384 $26,000 Both sanitary and storm sewers are video inspected. The golf course sediment basin requires sediment removal every two years. 50% Likely (Existing Funds from City Road Fund) N Inspect open channels, detention ponds, and structural BMPs for trash and debris, and clean as necessary. Include spot checks after intense storms. Inspect areas that generate significant waste more often during the rainy season. Dispose of waste properly and document all activities. Fix problems. 192 $13,000 ExF NPDES II SW Permit Minimum Measure #1.7 Municipal Operation: Pollution Prevention/Good Housekeeping Goal: To alter municipal facilities and actions to reduce pollution including structures, O/M land use practices, spill prevention, and recycling. (NOI #6.a. Develop a municipal O&M plan by the end of year 3, implement by the end of year 5. City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 10 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Required BMP 1.7G: Deicing BMPs Per the O&M plan, implement WQ BMPs for deicing and snow removal O&M practices on public praking lots, and roads. Measurable Goal: By the end of Permit Year 5, implement required deicing BMPs. (Costs are too low in Model Program) 384 $26,000 Deicing activities need to be reviewed, documented, and potentially modified to apply WQ protection BMPs. 90% Likely (Existing Funds from City Road Fund) N Make sure the City's plan fits the criteria outlined in Section 7.3.6.2 of the Model Program. Make and fund needed changes to include WQ BMPs 40 $2,600 ExF Required BMP 1.7H: Flood Mgmt BMPs Per the O&M plan, implement flood management project evaluation and review procedures. Measurable Goal: By the end of Permit Year 5, all new flood management project evaluations will include water quality considerations, and existing projects will be re-evaluated. 0 $0 City has a list of ten troublesome local maintenance/flooding locations. Corps of Engineers owns, operates, and maintains local levees, pumps, and flood plains. N/A N Y Select several priority projects for review over the permit period. Determine whether or not changes should be made to improve water quality protection. 0 $0 ExF Required BMP 1.7I: Employee Training Develop materials and conduct employee good houskeeping and O&M training. Measurable Goal: By the end of Permit Year 5, all SW and maintenance employees will receive training on enhanced O&M procedures. 40 $4,000 The City currently provides some O&M training. 50% Likely Y Training must be provided as needed to ensure that BMPs are properly used for all municipal operations that may affect water quality. Make sure training curriculum includes all topics addressed in the O&M Plan in BMP 1.7A. 0 $0 ExF Required BMP 1.7J: Pollution Plan and Permits Develop stormwater pollution prevention plans for all municipal facilities not already adressed above and where WQ impacts may occur (material storage areas). Submit industrial stormwater NPDES permit applications as needed for any "municipal industrial sites" (maint faclities, landfills, etc) that meet pemritting criteria. Measurable Goal: Survey municipal facilities, submit NPDES Industrial SW Permit applications immediately, develop immediately. (One time cost to develop and apply, ongoing cost to implement and comply) 60 $20,040 There is no pollution management plan for all municipal facilities. A new initiative is needed. Industrial stormwater permit applications are submitted as needed. 50% Likely N Assess and screen municipal facilities. Prepare site specific stormwater pollution prevention plans for municipal facilities that are not covered by the Industrial Stormwater General Permit but have a potential to impact surface waters. Provide training, and implement the plan. 30 $10,000 ExF Required BMP 1.7K: O&M Waste Disposal Properly dispose of wastes collected during BMP maintenance cleaning. ? ? Wastes are currently characterized first by the City, then taken to the appropriate facility. 100% Likely N No new funding needed. 0 $0 ExF Required BMP 1.7L: Municipal Building Good Housekeeping Implement WQ BMPs for use during O&M of municipal buildings (cleaning, painting, washing, etc.). 0% Likely Y Need to review activities at muncipal buildings and add WQ protection BMPs where needed. 1.7 Sub-Total: Municipal Operation: Pollution Prevention/Good Housekeeping 2,484 $188,040 City may choose to reprioritize other O&M work to shift existing funds and resources to cover these additional costs. 1,222 $90,600 City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 11 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Required BMP 1.8A: Record keeping and Annual Reporting Keep records and track program implementation and progress in meeting measurable goals. Measurable Goal: Submit an annual report to Ecology. 136 $10,800 City permitting is managed through the Environmental Engineer and the O/M Manager. Tracking and Reporting is done by the appropriate manager. 75% Likely N Record keeping requirements will affect many city departments and divisions. Annual reporting for NPDES will require assembling numerous records and other information about progress at meeting requirements. Section 8.1 of the Model Program provides example programs and activities that can be used to help demonstrate BMP effectiveness. And appendix 8A provides an example of what the annual report should contain. 36 $1,800 ExF 1.8 Sub-Total: Monitoring and Reporting 136 $10,800 75% 36 $1,800 Optional BMP 1.9A: It is difficult to estimate future tasks and resources needed in this category. A contingency of $10K-$20K/year is recommended. 0 $0 New initiative(s) may be needed. 0% Likely N 0 $0 ExF 1.9 Sub-Total: Additional NPDES II SW Permit Requirements 0 $0 N/A 0 $0 Required BMP 1.10A: Develop and Submit NPDES Permit Application to Ecology. One time cost. Not included in Model Program. 136 $10,080 New initiative needed. 0% Likely Y NPDES II Application is due to Ecology about June, 2006. Note that negotiation of an Individual Permit is likely to cost far more. 136 $10,800 ExF 1.10 Sub-Total: Notice of Intent 136 $10,080 136 $10,800 11,651 $857,044 6,359 $411,790 2.1 Form UIC Program: Required Required 2.1A: Locate and map publicly owned infiltration facilities. Document land uses draining to UICs. Measurable Goal: Undefined No model UIC Program No model UIC Program City has mapped publicly owned infiltration facilities (See Figure 4-3 in the Task 3d Interim SWM Report to Ecology). 100% Likely N Annual map updates will be required. May need to document land uses draining to UICs and other information like vicininty to wells and surface waters, etc. 20 $2,000 ExF *Note: Start-up and one-time program development or planning costs have been annualized over the first five years. On-going programmatic costs are for fully implemented programs. After five years, the annual budget should be reviewed and the rates adjusted up or down as needed. Capital costs (CIP) have been annualized over ten years with the average annual CIP cost added to the estimated annual program costs. NPDES II SW Permit Minimum Measure #1.8 Evaluation and Assessment Record Keeping and Reporting (SWM Program Management and Administration) Goal: Permit Administration/Management and Reporting. NOI: Record Keeping and Reporting: Meeting Ecology's requirements, as defined on page 11 of 22. NPDES II SW Permit Minimum Measure #1.9 Additional NPDES II SW Permit Requirements Goal: Additional State NPDES II SW Permit requirements will likely be added at a later date. (Note: This element is not included in the Eastern WA Model SWM Program.) NPDES II SW Permit Minimum Measure #1.10 Permit Application to Ecology Goal: Preparation of NPDES II Notice of Intent (NOI) and NOI Permit Negotiations with Ecology. (Note: This element is not included in the Eastern WA Model SWM Program.) NPDES II TOTAL Stormwater Program Element #2.0 - Underground Injection Control Program Goal: Compliance with future underground injection control (UIC) program requirements. Note: The State's UIC Rule is not final, and the State has developed no compliance guidance to suggest typical levels of effort or costs. Rule implementation is expected in January 2006. City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 12 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Required BMP 2.1B: For new UICs, comply with DOE presumptive standards, or develop regional risk based strategy for application of future stormwater infiltration systems (based on soils, GW, drinking water wells, etc., should include some field work and soil property testing). Measurable Goal: Undefined (One time cost.) City has a wellhead protection plan. High risk infiltration areas are mapped in the wellhead protection area 3-year time of travel. 0% Likely N A risk-based strategy needs to be developed for stormwater infiltration. Wellhead protection areas are dependant on many factors and should be updated periodically. Assume that this begins to be addressd during the development of Kennewick's SWMP. 200 $20,000 ExF Required BMP 2.1C: Develop a UIC asessment protocol, identify existing publicly owned infiltration systems in areas with high risk for groundwater degradation by stormwater. Measurable Goal: Undefined (One time cost.) As part of the Wellhead protection plan, and according to the State's specifie contaminant source inventory (CSI), the City lists all the potential ground water contaminant sources located within the wellhead protection areas. The list is updated every two years. 100% Likely N Continue to update the list every two years. Need to ensure that wellhead protection assessment is adequate to meet UIC needs, need to aassess existing UICs outside the wellhead protection area as well. Assume that this begins to be addressd during the development of Kennewick's SWMP. 350 $35,000 ExF Required BMP 2.1D: Develop a written management and/or replacement strategy (retrofit program) that will reduce pollutant loading to groundwater by specifically focusing on the systems identified in step 2.1C above. Measurable Goal: Undefined (One time cost.) Chapter 5.6 of the Wellhead Protection Plan includes Water Supply Replacement Alternatives. Chapter 5.8 suggests Financial Resources. 100% Likely Y Need to develop a "retrofit plan" that specifically addresses UIC needs. It may build upon the wellhead protection plan. Retorfit activities may include structural and non-structural pollutant reducing methods. Decommissioning of some UICs may be needed. Assume that this begins to be addressd during the development of Kennewick's SWMP. 200 $20,000 ExF Required BMP 2.1E: Develop any needed UIC staff training material neded to implement the "retrofit plan" (source control, spill response, illicit discharges, proper O&M, etc.) Measurable Goal: Undefined Staff training is provided as needed. The City performs tabletop exercises and works with the Wa. State Military Dept. to develop incident command center training. 75% Likely Y Training can be combined with NPDES training activities 50 $5,000 ExF 2.1 Subtotal: Form UIC Program 75% 820 $82,000 2.2 Implement UIC Program: Required BMP 2.2A: Implement adaptive annual UIC management strategy (retrofit plan, per 2.1D). As needed, include: education, projects, monitoring, effectiness assessment, enhanced O&M, source contorls, spill response, and opportunistic structural retrofits. Measurable Goal: Undefined Not currently performed. New initiative needed. 0% Likely Y Need to develop and implement a formal defensible UIC management and retrofit plan. As needed, include: education, projects, monitoring, effectiness assessment, enhanced O&M, source contorls, spill response, and opportunistic structural retrofits. The Wellhead Protection Plan documents some suggested public education ideas. Some cost savings can be realized by meshing with NPDES programs. 100 $10,000 ExF Required BMP 2.2B: Register all publicly owned infiltration systems. Include retrofit and decommissioning info as needed. Measurable Goal: Undefined City has located and mapped, but not registered, publicly owned infiltration facilities. 50% Likely Y Locate any remaining infiltration systems. Register all public infiltration systems. Include details of decommissioning and "retorfitting" activities to avoid a non-Rule Authorized determination by Ecology. 150 $15,000 ExF Required BMP 2.2C: Develop and enforce UIC construction standards. Use Ecology presumptive standards or develop defensible demonstrative standards. Measurable Goal: Undefined City inspects public storm drainage facilities. Publicly owned facilities are constructed to City standards. Private facilities are inspected to ensure compliance with the approved design. Pretreatment is not a current requirement. 75% Likely N City will need to adopt UIC design standards and review UIC construction plans and inspect private facilities. Incorporate this work with NPDES standards and plan review/site inspection tasks to reduce costs. 150 $15,000 ExF City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 13 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Required BMP 2.2D: Perform post construction management and source control for public systems, provide regular inspection and maintenance. Measurable Goal: Undefined Annual drywell maintenance is performed. 80% Likely Y Regular O/M of City dry wells is annually performed. Assume source control efforts are partially covered by NPDES estimates. Formal documentation of pollution reducting activities may be needed. 200 $20,000 ExF Required BMP 2.2E: Provide ongoing staff training on UIC pollution prevention and O&M. Measurable Goal: Undefined Not currently performed. New initiative needed. 0% Likely Provide UIC Rule training for staff. Mesh with NPDES training for cost savings. 20 $2,000 ExF Required BMP 2.2F: Conduct monitoring as needed to validate retorfit program and allow use of adaptive management, and maintain Rule Authorization. Measurable Goal: Undefined (Cost estimate is low.) Not currently performed. New initiative needed. 0% Likely N The City's monitoring program will be based on final UIC Rule and retrofit plan conditions. 50 $5,000 ExF Required BMP 2.2G: Provide reporting to Ecology as needed to illustrate the retrofit plan is being implemented and maintain Rule Authorization. Measurable Goal: Undefined The City currently reports to Ecology regularly, as required by their waste discharge permit for the wastewater treatment plan, and as required by construction stormwater permits. 0% Likely N Periodic reporting to Ecology may be required to demonstrate ongoing compliance with the UIC Rule. 40 $4,000 ExF 2.2 Subtotal: Implement UIC Program 0 $0 710 $71,000 0 $0 1,530 $153,000 Required BMP 3.1 - Land Use Decisions and Regulations Assess stormwater impacts when making land use decisions. Reduce stormwater runoff, impervious surfaces, and retain native vegetation. Measurable Goal: Defined in ESA Stormwater Checklist (Addressed by NPDES II SW Permit.) No model ESA Program Costs No model ESA Program Costs Not currently performed. Presumed to be addressed by NPDES II SW Permit requirements BMPs 1.5 and 1.6. 100% Likely Y Consider developing design standards that encourage devolpers to retain existing native vegetaion and use low impact design criteria (LID). Can be adressed under NPDES. 0 $0 ExF Required BMP 3.2 - Technical Standards Adopt standards equivalent to the DOE Manual. Measurable Goal: Defined in ESA Stormwater Checklist (Addressed by NPDES II SW Permit.) Presumed to be addressed by NPDES II SW Permit requirements BMPs 1.5 and 1.6. Likely N Revision of existing City SW related ordinances may be needed. Adressed under NPDES. 0 $0 ExF Required BMP 3.3 - Inspection/Enforcement Measurable Goal: Defined in ESA Stormwater Checklist (Addressed by NPDES II SW Permit.) Presumed to be addressed by NPDES II SW Permit requirement BMP 1.5. 100% Likely N 0 $0 ExF Required BMP 3.4 - Maintenance Standards/Proposal Measurable Goal: Defined in ESA Stormwater Checklist (Addressed by NPDES II SW Permit.) Presumed to be addressed by NPDES II SW Permit requirement BMP 1.7. 100% Likely N 0 $0 ExF Stormwater Program Element #3.0 - Endangered Species Act: 4(d) Rule Goal: Address stormwater related requirements of ESA 4(d) Rule, as defined by Tri County / King County prepared 4(d) Rule. Underground Injection Control Program TOTAL City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 14 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Required BMP 3.5 - Source Control Adopt source control standards BMP by DOE. Measurable Goal: Defined in ESA Stormwater Checklist (Addressed under NPDES II SW Permit and UIC.) See KMC 14.22 and 14.28 (attached). Presumed to be addressed by NPDES II SW Permit requirements BMPs 1.5, 1.6, and 1.7. 100% Likely N 0 $0 ExF Required BMP 3.6 - Illicit Discharge Measurable Goal: Defined in ESA Stormwater Checklist (Addressed under NPDES II SW Permit.) Presumed to be addressed by NPDES II SW Permit requirement BMP 1.4. 100% Likely N 0 $0 ExF Required BMP 3.7 - Public Education Measurable Goal: Defined in ESA Stormwater Checklist (Addressed under NPDES II SW Permit: need to add habitat issues.) Presumed to be addressed by NPDES II SW Permit requirement BMP 1.2. 100% Likely N 0 $0 ExF Required BMP 3.8 - Public Involvement/Outreach Measurable Goal: Defined in ESA Stormwater Checklist (Addressed under NPDES II SW Permit.) Presumed to be addressed by NPDES II SW Permit requirement BMP 100% Likely N 0 $0 ExF Required BMP 3.9 - Governmental Coordination Measurable Goal: Defined in ESA Stormwater Checklist Currently occurring, no new initiative needed. 100% Likely N 0 $0 ExF Required BMP 3.10 - Monitoring Measurable Goal: Defined in ESA Stormwater Checklist (Addressed under NPDES II SW Permit, and UIC.) Presumed to be addressed by NPDES II SW Permit requirement BMP 1.8. 100% Likely N 0 $0 ExF Required BMP 3.11 - Stormwater Planning Measurable Goal: Defined in ESA Stormwater Checklist Presumed to be addressed in NPDES II SW Permit and UIC Program. 100% Likely N 0 $0 ExF Required BMP 3.12 - Capital Improvement Program Measurable Goal: Defined in ESA Stormwater Checklist Capital needs will be included in the Kennewick Stormwater Management Plan by the City. 100% Likely N 0 $0 ExF Required BMP 3.13 - Habitat Enhancement/Rehabilitation Measurable Goal: Defined in ESA Stormwater Checklist New initiative may be needed. 0% Likely N The City has few habitat enhancement opportunities. 0 $0 ExF Required BMP 3.14 - Habitat Acquisition Measurable Goal: Defined in ESA Stormwater Checklist New initiative may be needed. 0% Likely N The City has few habitat enhancement opportunities. 0 $0 ExF 0 $0 100% 0 $0 Optional BMP 4.1: Manage stormwater in incorporated areas consistent with surface water quality strategy, as defined in WRIA Plan, if completed. Measurable Goal: Undefined 0 $0 Presumed to be addressed by NPDES II SW Permit, UIC, and TMDL/303(d) requirements. 100% Likely N 0 $0 ExF Endangered Species Act: 4(d) Rule TOTAL: Stormwater Program Element #4.0 - W.R.I.A. and Regional Wastershed Planning Goal: Meet responsibilities identified in the WRIA or local watershed plan. (The City of Kennewick is involved with WRIA 31.) There may be overlap between the WRIA Planning and the Kennewick SW Plan/Program that includes; NPDES II SW Permit, ESA, UIC, CIP, Interlocal Agreements, Regional Coordination and Funding. City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 15 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Optional BMP 4.2: Update land use regulations to improve off-channel connectivity, and improve management of riparian areas consistent with Habitat Strategy, as defined in WRIA Plan, if completed. * Measurable Goal: Undefined (*May overlap with the Kennewick SW Plan, NPDES II SW Permit, UIC, and ESA.) 0 $0 Presumed to be included in GMA required planning and ordinance. 100% Likely N 0 $0 ExF Optional BMP 4.3: Surface Water Quality Strategy: Participate in interagency coordination, as defined in Watershed Plan, if completed. Measurable Goal: Undefined 0 $0 Not currently performed. Presumed to be addressed by NPDES and UIC requirements. New initiative may be needed if Ecology requires WQ monitoring as part of NPDES II or UIC Rules. 100% Likely N 0 $0 ExF Optional BMP 4.4: Fish Habitat Enhancement if in Watershed plan. Measurable Goal: Undefined Overlaps with the Kennewick SWM Plan, UIC, and ESA.) 0 $0 Presumed to be addressed by ESA Requirement 3.13 and 3.14. 100% Likely N 0 $0 ExF 0 $0 100% 0 $0 Water Quality related activities may include: Optional 5.1 Actively participate in development of for receiving waters. Measurable Goal: Undefined 0 $0 New initiative may be needed in the future. 100% (At this time) Likely Y May not be applicable at this time. 0 $0 ExF Optional 5.2 Monitoring of outfall quality for discharges to impaired waters. Measurable Goal: Undefined 0 $0 New initiative may be needed in the future. 100% (At this time) Likely Y May not be applicable at this time. 0 $0 ExF Optional 5.3 If stormwater outfalls are allocated a load in a TMDL (or if Ecology uses the same approach for MS4 NPDES II SW Permits that they intend to use for Industrial Stormwater and WW NPDES II SW Permits in impaired water locations, which is to set an interim load), then other things may be required like: ~ Stormwater BMP monitoring , ~ Enhanced source control or retrofitting treatment on existing discharged, and ~ Annual reporting Measurable Goal: Undefined 0 $0 New initiative may be needed in the future. 100% (At this time) Likely Y May not be applicable at this time. 0 $0 ExF Stormwater Program Element #5.0 - Water Quality: Local 303(d) Listed Waters and TMDL Recovery Plans Goal: Participate in local TMDL Studies; meet waste land allocation requirements as defined in the TMDL Compliance Document. Water Quality Certain reaches of the Columbia River have been listed on the 303(d) water quality violations list for temperature and dissolved gas violations. At this point in time it does not seem likely that the current TMDL studies for the Columbia River will affect the City of Kennewick, however, it is possible that the City may be subject to one, or more of these studies in the future. To prepare for the future, as additional surface water management, treatment, and restoration needs are identified, compliance activities, roles, costs and staffing may need to be entered into this list of regional surface water management needs. WRIA and Regional Watershed Planning TOTAL: City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 16 otak ---PAGE BREAK--- Required or Optional*1 Regulatory Compliance BMP Description (Large Community w/ Pop. > 10,000) Year #5 Annual Labor (Hours)*2 Year #5 Annual BMP Cost Describe Related BMP Currently In Use At Any Level, Include Responsible Staff*3 Approx. Level of BMP Compliance Need New Funding Source? (Y/N) Activity for Regional Consolidation (Y/N) Notes or "Gap" Between Required BMPs and Those Currently in Place Annual Labor (Hours)*4 Annual BMP Cost Recomm. Source of Funds*5 KENNEWICK COMPREHENSIVE STORMWATERPLAN REGULATORY REQUIREMENTS - DETAILED GAP ANALYSIS BMP/Activity Required for Compliance Summary of Current Activities/BMPs In Place Locally Activities/BMPs Needed Locally for Regulatory Compliance (Defined Service Level Selected by City to Achieve Regulatory Compliance) Optional 5.4 Regional Monitoring Program to establish baseline conditions and evaluate surface water program effectiveness. Measurable Goal: Undefined (Included in Labor/Budget of 5.2) 0 $0 New initiative may be needed in the future. 100% (At this time) Likely Y May not be applicable at this time. Recommendation to be provided by the Kennewick Stormwater Management Plan. 0 $0 ExF 0 $0 100% (At this time) 0 $0 Optional 6.1 Office Equipment: Per each new employee: ~ Desk and chairs ~ Computer ~ Software ~ Supplies ~ Bookshelf ~ Files ~ Telephone ~ Office space and utilities 0 $10,000 Office equpment is purchased on an as-needed basis. N/A Likely N Most funding included with general City overhead. Some additonal funds should be set aside to purchase additional equipment for new FTEs. 0 $10,000 ExF Optional 6.2 Equipment (Monitoring): ~ Vehicle, maintenance, insurance, and gas ~ Safety equipment ~ Clothing; boots, vests, etc. ~ pH meter ~ Turbidometer ~ D.O. probe ~ Temperature probe ~ Sediment sieves ~ Field notebooks, supplies ~ Flow meter ~ Gauging stations ~ Various chemicals ~ Coolers ~ Sample transport/mailing 0 $0 The City does not currently use any water quality monitoring equipment. N/A Likely Y Currently WQ Monitoring is not required by Ecology. New equipment may be needed in the future. These one- time costs are good candidates for shared funding through interlocal agreements. 0 $0 ExF Optional 6.3 Equipment (Maintenance): ~ Vactor trucks ~ Dump trucks ~ Vehicles ~ Pipe ~ Culverts ~ Man holes ~ Pumps ~ Hoses ~ Decant facility ~ Street vacuum sweeper ~ Back hoes ~ Front-end loaders ~ Shovels, locks, etc. ~ Drying beds ~ Disposal site ~ Rock/berming materials ~ Spill response equipment 0 $25,000 The City's O/M program already includes funding for maintenance of equipment. New equipment is purchased on an as-needed basis. N/A Likely N These funds are in addition to current O/M funds. 0 $25,000 ExF Optional 6.4 Professional Services ~ Consultant 0 $0 To be determined. N/A Likely Y 0 $0 ExF Optional 6.5 Miscellaneous Equipment (for City) 0 $0 To be dtermined as needed. N/A Likely N 0 $0 ExF 0 $35,000 N/A 0 $35,000 11,651 $892,044 7,889 $599,790 Regional Stormwater Program, GRAND TOTAL: Equipment & Services TOTAL: Water Quality TOTAL: Stormwater Program Element #6.0 - SWM Equipment & Services Goal: Provide necessary equipment and services to fully implement SWM Program. Each agency is requested to list new, major pieces of equipment that may be needed to comply with the terms and conditions of the NPDES II Stormwater Permit and the draft UIC Rule. Once identified, opportunities for regional consolidation will be explored. City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 17 otak ---PAGE BREAK--- Labor (Hours) BMP Costs Labor (Hours) BMP Costs Compared with E. Wash. Model Program Percentage Complete Annual Labor (Hours) Annual Costs Annual Labor (Hours)* Annual Costs Optional 1.1 Sub-Total: Start-up Activities 368 $32,000 0 $0 N/A 50% 0 $0 184 $16,000 All hours will actually be needed in Year 1. Hours shown are 1/5 of total required. Required 1.2 Sub-Total: Public Education & Involvement 369 $36,954 576 $58,590 1 of 6 BMPs 0% 0 $0 576 $58,590 Need formal education program. Cost includes $28,000 for printing and distribution of materials. Required 1.3 Sub-Total: Public Involvement / Participation 457 $34,864 372 $28,480 2 of 3 BMPs 75% 200 $8,170 97 $7,265 City currently responds to public complaints, need formal program to solicit public comment on SWM program. Includes $2,400 for materials. Required 1.4 Sub-Total: Illicit Discharge Elimination 818 $76,464 2,218 $185,240 All 7 BMPs 75% 500 $21,300 1,458 $74,500 City has mapped much of existing system, has legal ordinance, needs to create detection, screening, and response plan. Includes $1,600 for materials. Required 1.5 Sub-Total: Construction Site Stormwater Runoff Control 1,856 $95,649 3,838 $239,980 All 6 BMPs 50% 500 $24,800 1,996 $106,085 City has inspection program, needs erosion and sediment control ordinance. Includes $6,000 for materials. Required 1.6 Sub-Total: Post-Construction Stormwater Management 626 $46,632 1,598 $116,880 2 of 6 BMPs 75% 900 $46,486 654 $46,150 Task covers Development Review/GMA, and Engineering Support to other Departments. Includes $13,500 for materials. Required 1.7 Sub-Total: Municipal Operation: Pollution Prevention/Good Housekeeping 718 $55,912 2,484 $188,040 1 of 10 BMPs 50% 3,300 $186,098 1,222 $90,600 Existing maintenance levels are adequate. Potential cost savings in shifting staff time to Program Element 1.4. Equipment repair and replacement included in Program Element #6 Required 1.8 Sub-Total: Monitoring and Reporting 136 $10,800 136 $10,800 Annual Reporting 75% 100 $4,860 36 $1,800 Staff time each year on annual reporting will cover both NPDES and ESA requirements. N.A. 1.9 Sub-Total: Additional NPDES II SW Permit Requirements N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Optional 1.10 Sub-Total: Permit Application - 2006 136 $10,800 N/A N/A N/A N/A 300 $14,880 136 $10,800 Permit application activities needed every 5 years. Potential cost savings by combining effort with Program Element 1.8. 5,484 $400,075 11,222 $828,010 ~65% 5,800 $306,594 6,359 $411,790 (5.6 FTE) (2.9 FTE) (3.2 FTE) Required 2.1 Subtotal: Form UIC Program 140 $14,000 N/A N/A N/A 0% 0 $0 820 $82,000 Will need 140 hours and $14,000 for start-up costs in Year 1. Required 2.2 Subtotal: Implement UIC Program 700 $50,000 700 $50,000 N/A 0% 200 $9,920 710 $71,000 840 $64,000 700 $50,000 0% 200 $9,920 1,530 $153,000 (0.35 FTE) (0.1 FTE) (0.8 FTE) Stormwater Program Element #2.0 - Underground Injection Control Program Goal: To comply with future underground injection control (UIC) program requirements, and protection of the City's aquifer water supplies. Underground Injection Control Program TOTAL NPDES II SW Program does not Include: SWM Program Management, CIP, Regional Planning/Coordination, Sensitive Areas, or UIC Regulatory Compliance Gap Activities, BMPs, and Additional Resources Needed for Regulatory Compliance *Required activities are those required by regulation. Optional activities are additional recommended BMPs *Difference in Year 5 Requirement and current City Activities **Cost based on averageof $50 per staff hour (includes 46% for benefits). Stormwater Program Element #1 - NPDES II SW Municipal Permit Goal: To comply with the E.Wa. Model SWM Program and E.Wa. NPDES SW II Permit. NPDES II TOTAL CITY OF KENNEWICK COMPREHENSIVE STORMWATER PLAN REGULATORY REQUIREMENTS - GAP ANALYSIS SUMMARY Comments Years 1-5 Average Annual Labor / BMP Cost Required or Optional Activity* Regulatory Compliance BMP Commitments made by City's Notice of Intent (March 10, 2003) BMP/Activity Required for Compliance (Based on Model Municipal SWM Program for E. Wash. Sept. 2003) Year #5 Annual Labor / BMP Cost Summary of City's Current Activities/BMPs (Annual Labor and Cost from Interviews with City Staff) City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 18 otak ---PAGE BREAK--- Labor (Hours) BMP Costs Labor (Hours) BMP Costs Compared with E. Wash. Model Program Percentage Complete Annual Labor (Hours) Annual Costs Annual Labor (Hours)* Annual Costs Gap Activities, BMPs, and Additional Resources Needed for Regulatory Compliance *Required activities are those required by regulation. Optional activities are additional recommended BMPs *Difference in Year 5 Requirement and current City Activities **Cost based on averageof $50 per staff hour (includes 46% for benefits). CITY OF KENNEWICK COMPREHENSIVE STORMWATER PLAN REGULATORY REQUIREMENTS - GAP ANALYSIS SUMMARY Comments Years 1-5 Average Annual Labor / BMP Cost Required or Optional Activity* Regulatory Compliance BMP Commitments made by City's Notice of Intent (March 10, 2003) BMP/Activity Required for Compliance (Based on Model Municipal SWM Program for E. Wash. Sept. 2003) Year #5 Annual Labor / BMP Cost Summary of City's Current Activities/BMPs (Annual Labor and Cost from Interviews with City Staff) Required 3.1 - 3.14 Subtotal: Summary of 14 ESA SWM Requirements. 0 $0 N/A N/A N/A 0% 0 $0 0 $0 Covered in NPDES II Program 0 $0 0 $0 N/A 0% 0 $0 0 $0 Optional 6.1 Subtotal: Office Equipment 0 $0 N/A N/A N/A As Needed As Needed As Needed 0 $10,000 Optional 6.2 Subtotal: Equipment (Monitoring) 0 $0 N/A N/A N/A As Needed As Needed As Needed 0 $0 Water Quality monitoring is currently not required by Ecology Optional 6.3 Subtotal: Equipment Maintenance 0 $35,000 N/A N/A N/A As Needed As Needed As Needed 0 $25,000 Optional 6.4 Subtotal: Equipment Services 0 $0 N/A N/A N/A As Needed As Needed As Needed 0 $0 0 $35,000 0 $0 As Needed As Needed As Needed 0 $35,000 Optional 8.1 General Activities 0 $0 N/A N/A N/A 0% 0 $0 0 $0 0 $0 0 $0 0% 0 $0 0 $0 6,324 $499,075 11,922 $878,010 6,000 $316,514 7,889 $599,790 3.2 FTE 6.0 FTE 3.0 FTE 3.9 FTE Endangered Species Act: 4(d) Rule TOTAL: Stormwater Program Element #3.0 - Endangered Species Act: 4(d) Rule Goal: To address strormwater related requirements of ESA 4(d) Rule, as defined by Tri County / King County prepared 4(d) Rule, and reduce the risk of third party lawsuits. Stormwater Program Element #4.0 - Regional Watershed Planning Goal: Undefined at this time. The City has limited participation in WRIA 31 activities. Discussions with staff show an interest in increasing regional cooperation as a way to share technical expertise and and reduce future costs of regulatory compliance. Interlocal agreements for the sharing of equiment, staff, and services are possible, though may require additional up-front staff time. Stormwater Program Element #5.0 - Water Quality: Local 303(d) Listed Waters and TMDL Recovery Plans Goal: Undefined at this time. The City is not currently impacted by any 303(d) Listed Waters or TMDL recovery plans. Stormwater Program Element #6.0 - Equipment & Services Goal: To repair and/or replace equipment as needed. Total annual SWM Program costs $790,804 and employs a total of 6.3 FTE. CIP Program costs are additional. Comprehensive Stormwater Plan GRAND TOTAL: General Activities TOTAL: Equipment & Services TOTAL: Stormwater Program Element #7.0 - Capital Improvements Goal: To design and construct needed capital projects to reduce flooding and protect public safety. CIP Costs are addressed in separate analysis. Stormwater Program Element #8.0 - General Surface Water Management, Regulatory, and Planning Activities Goal: (Could be used to track non-regulatory SWM management, planning, administration, budgeting/funding, and staffing activities and costs currently included in NPDES II Permit Element 1.7 amd 1.8) City of Kennewick Comprehensive Stormwater Plan K:\project\30300\30386\Reports\Final Report\Appendices\Appendix D3b - Kenn Gap Analysis.xls 19 otak ---PAGE BREAK--- ---PAGE BREAK--- Appendix E — NPDES II Permit Application to Ecology ---PAGE BREAK--- ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 1 of 21 National Pollutant Discharge Elimination System (NPDES) Phase II Stormwater Permit Application Phase II Municipal Separate Storm Sewer Systems (MS4s) The purpose of this application is for local governments or special districts to apply for a National Pollutant Discharge Elimination System (NPDES) permit to discharge stormwater runoff from a Phase II municipal separate storm sewer system (MS4s). The Department of Ecology may request additional information and a notice of intent at a later date, upon development of a general permit. MS4s seeking coverage must complete this application, based on existing information, and return it to the Department of Ecology before March 10, 2003. You may print this form and complete it by hand, or download it from our website at: www.ecy.wa.gov/programs/wq/stormwater/index.html. An authorized signature is needed to complete the application. All information should be included on this form. Supporting documents should be referenced in the text only. No attachments are necessary, other than those that may be required under the Map Requirements. Mail completed application to: Department of Ecology Water Quality Program PO Box 47600 Olympia, WA 98504-7600 Ecology will send you an acknowledgment of receipt. If you have questions about this application, please contact Janice Sedlak at (360) 407-6470 or email her at [EMAIL REDACTED]. Part I. General Information 1. MS4 Operator Name of city, county, special district, or other public entity: City of Kennewick Street Address: 210 West 6th Avenue O. Box 6108) City, State, Zip: Kennewick, WA 99336 Ownership status: Federal State Private Public Other Entity 2. Local staff contact (person responsible for program implementation and coordination): Name: Stephen R. Plummer Phone: (509) 585-4287 Title: Project Engineer E-mail: [EMAIL REDACTED] Does your MS4 presently have a web site? (If yes, list address ci.kennewick.wa.us ) Yes / No If so, are your ordinances available on your website Yes / No If not, where are your ordinances available? N/A ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 2 of 21 . Operator Type ; City County Town Flood Control District Drainage District Other (list): 4. Description of Storm Sewer System A. Area of land served by your MS4 (in square miles): If city, town, or special district give: If county give: Area within current corporate boundaries 23.58 Area in square miles Additional area of urban growth area (UGA) 5.72 Area that is urbanized Area that is urbanized (2000 Census) 24.32 For all MS4s, give 2000 Census population for area served 54,963 Area located on Indian lands (if any) N/A B. Storm Drainage Infrastructure: Please provide estimates, using the most accurate information available at this time, for the following storm drainage infrastructure features owned or operated by the MS4. Conveyance system: Flow Control system: Open ditches (miles or feet) Detention facilities (estimate number operated by MS4) 1 Regional Storm sewers (miles or feet) 83.33 miles Retention facilities (estimate number operated by MS4) 3 Facilities: Outfalls (estimate number) 6 1 Catch basins (estimate number) 4200 Treatment system: Treatment facilities (estimate number operated by MS4) 0 5. Map Requirements: Include a map or maps that identifies: • City, county, or district service area boundaries • State or Federal vocational/technical/college/university campuses and military institutions • Urban area (as defined by the 2000 Census) • GMA urban growth area (UGA), even if partially in an Urban Area • Municipal/county wastewater treatment plants, outfalls, uncontrolled sanitary landfills, vehicle fleet maintenance centers, power plants, airports, and other municipally owned or operated industrial activities • Arterial city or county roads, (additional roads if needed), drainage basins, and receiving waters Please assure that information is clearly readable. Submit GIS maps if available, and only in .pdf format on a CD- ROM. Multiple maps must be of the same scale. 1:1000 or 1:2000 scales are recommended. Submit paper maps folded to 8.5 x 11.” ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 3 of 21 6. List all named receiving waters within your jurisdiction and ¼ mile and indicate those identified as impaired pursuant to Clean Water Act Section 303(d), and those with an existing Total Maximum Daily Load (TMDL). This information is available at: www.ecy.wa.gov/programs/wq/links/impaired_wtrs.html. WRIA Water Body Name (and New ID # if avail.) Impaired? Parameters TMDL? Columbia River Yes / No Yes / No 37 East Fork Amon Creek Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Yes / No Please list any water bodies for which a TMDL, pollution prevention plan, water quality monitoring program, or other relevant program is in place or in development. Columbia River 7. Does your MS4 have public infiltration facilities (infiltration basins or dry wells)? Yes / No If yes, estimate the percentage of the jurisdiction that discharges to these facilities. 75% 8. Is your MS4 interconnected to a Washington State Dept. of Transportation facility? Yes / No If yes, please identify : 9. Is your MS4 interconnected, or do you discharge to another jurisdiction? If yes, identify below. Yes / No Jurisdiction Name Contact Ultimate receiving water Kennewick Irrigation District Columbia River/Amon Creek Columbia Irrigation District Columbia River ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 4 of 21 Part II. Your Proposed Stormwater Management Program This application requires you to identify Best Management Practices (BMPs) currently performed by your MS4, and provide information on your planned stormwater management program and proposed BMPs. The following six sections correspond to the six minimum control measures for a Phase II stormwater quality management program. Minimum Control Measures The National Pollutant Discharge Elimination System (NPDES) Phase II Rule defines a stormwater management program composed of six minimum control measures that, when implemented together, are expected to reduce pollutants discharged into receiving water bodies to the Maximum Extent Practicable (MEP). The six control measures include: 1. Public Education and Outreach on Stormwater Impacts 2. Public Involvement/Participation 3. Illicit Discharge Detection and Elimination 4. Construction Site Runoff Control 5. Post-Construction Stormwater Management in New Development and Redevelopment 6. Pollution Prevention/Good Housekeeping for Municipal Operations Each minimum control measure requires the selection and implementation of BMPs that comprehensively address the specific stormwater issues in your area. The minimum requirements are provided in Appendix I as the minimum level necessary to comply with 40 CFR 122.34. Regulatory guidance from 40 CFR 122.34 is also provided for each minimum control measure. Additional guidance on selecting BMPs and developing measurable goals can be found at the following EPA website: www.epa.gov/npdes/stormwater/measurablegoals/index.htm. Instructions: For each minimum control measure, state your control objective and describe BMPs selected for implementation in your jurisdiction. For each BMP, include a brief description, measurable goal, and milestones as appropriate towards achieving that goal. Indicate if the BMP is part of an existing program, and if another entity will share responsibility for implementing the BMP. In cases where another entity will perform one or more BMPs or components thereof on behalf of the permittee, specifically describe the activities each entity will conduct, and include reference to legal agreement where appropriate. List as many BMPs as necessary to fulfill the requirements of 40 CFR 122.34 as referenced in Appendix I. If you have more than 2 BMPs for a control measure, copy/paste additional tables as necessary. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 5 of 21 1. Public Education and Outreach on Storm Water Impacts Does your MS4 presently perform public education and outreach activities on stormwater impacts? Yes / No Minimum Measure Objective 1: Develop and implement a storm water education and outreach strategy BMP 1(a): Develop and implement a storm water education and outreach strategy Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Develop and implement a storm water education and outreach strategy Milestones: By the end of permit year 3 2. Public Involvement/Participation Does your MS4 presently provide opportunity for the public to be involved or participate in the development or implementation of a stormwater management program? Yes / No Minimum Measure Objective 2: Implement a public involvement/participation program in compliance with State, Tribal and Local public notice requirements. BMP 2(a): Hold public meetings and solicit public review of storm water management plan. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Publish two public notices and hold two public meetings Milestones: By the end of permit year 1. 3. Illicit Discharge Detection and Elimination Does your MS4 presently have a program for the detection and elimination of illicit discharges to the storm sewer? Yes / No Does your MS4 presently have an ordinance in place that enables you to prevent and eliminate illicit discharges to the storm sewer? Yes / No Minimum Measure Objective 3: Develop a storm sewer map, showing the location of all outfalls and the names and location of all waters of the US that receive discharges. Prohibit by ordinance non-storm water discharge to the storm drain system. Develop and implement an illicit discharge detection plan. Inform employees, businesses and general public of the hazards of illegal discharges. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 6 of 21 BMP 3(a): Create a storm sewer system map showing all known storm drain outfalls to receiving waters. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Map and field verify all known outfalls to receiving waters. Milestones: By the end of permit year 3. BMP 3(b): Develop and enforce an ordinance prohibiting illicit discharges and illegal dumping and authorizing enforcement actions, including on private property. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Adopt an ordinance that prohibits illicit discharges to the storm drain system. Milestones: By the end of permit year 2. BMP 3(c): Develop an illicit discharge detection plan. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Develop an illicit discharge detection plan. Milestones: By the end of permit year 5. BMP 3(d): Visually inspect all known outfalls during dry weather. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Visually inspect all known outfalls during dry weather in conjunction with BMP 3(a). Milestones: By the end of permit year 5. BMP 3(e): Develop and implement a spill response plan. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Develop and implement a spill response plan, including coordination with the Department of Ecology’s Spill Response Team. Milestones: By the end of permit year 5. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 7 of 21 BMP 3(f): Develop and implement an enforcement plan to ensure compliance with local ordinances. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Develop and implement an enforcement plan to ensure compliance with local ordinances with regards to illicit discharges, construction site discharges and post-construction discharges.. Milestones: By the end of permit year 5. BMP 3(g): Provide training opportunities for staff on proper BMP’s for spills and illicit discharges. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Develop and implement an annual training program for appropriate staff. Milestones: By the end of permit year 5. 4. Construction Site Run-off Control In the following spaces, indicate if your MS4 presently performs these activities related to construction site runoff control. Activities: Existing? Construction site plan review Yes / No Responding to public input and complaints Yes / No Enforcement and inspection procedures Yes / No Training and education Yes / No Does your MS4 presently have an ordinance addressing construction site run-off control? If yes, code number - Yes / No Minimum Measure Objective 4: Develop and implement procedures for site inspection and enforcement of control measures, and for the receipt and consideration of information submitted by the public. BMP 4(a): Adopt an ordinance for erosion and sediment controls for operators disturbing one acre or more. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Adopt an ordinance for erosion and sediment controls. Milestones: By the end of permit year 2. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 8 of 21 BMP 4(b): Provide training opportunities for plan reviewers and field inspectors in erosion and sediment control. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Provide annual training for reviewers and inspectors. Milestones: By the end of permit year 5. BMP 4(c): For all construction sites greater than one disturbed acre, review site plans to ensure that erosion and sediment controls and post-construction controls are included and are in accordance with local ordinance. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Provide annual training for reviewers and inspectors. Milestones: By the end of permit year 5. BMP 4(d): Publish a phone number, or equivalent system, to receive public input on construction site runoff issues. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Publish a phone number, or equivalent system, to receive public input and develop a process to forward the information to field inspectors. Milestones: By the end of permit year 5. BMP 4(e): Inspect all construction sites greater than one disturbed acre during the construction period that are regulated local ordinance adopted in BMP 4(a). Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Inspect all regulated construction sites at least once during the construction period. Milestones: By the end of permit year 5. BMP 4(f): Provide information on erosion and sediment control training opportunities to construction operators. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Provide training information to local construction operators. Milestones: By the end of permit year 5. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 9 of 21 5. Post-Construction Stormwater Management in New Development and Redevelopment Please answer the following questions regarding post-construction stormwater management in new development and redevelopment. Does your MS4 presently have a development permit process in place? Yes / No Does your MS4 presently have a stormwater management technical manual? Yes / No If yes, has the MS4 adopted the Ecology 2001 Stormwater manual, or an equivalent manual? If no, what manual is currently adopted/used? Please list - City of Kennewick Standard Specifications. Yes / No Does your MS4 presently have a plan review process for new development and redevelopment? Yes / No Does your MS4 presently inspect new stormwater facilities? Yes / No Does your MS4 presently inspect existing stormwater facilities? Yes / No Does your MS4 presently have a stormwater ordinance addressing post construction stormwater controls? If yes, code number - Yes / No Does your MS4 presently promote and/or provide incentives for Low Impact Development? Yes / No Minimum Measure Objective 5: Develop, implement and enforce a regulatory program to address runoff from new development and redevelopment projects that disturb one or more acres. Develop and implement strategies that include BMP’s appropriate to our community and ensure maintenance of same. BMP 5(a): Adopt an ordinance requiring post development runoff controls. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Adopt an ordinance requiring post development runoff controls. Milestones: By the end of permit year 2. BMP 5(b): Develop and implement a plan to address post-construction runoff controls during the plan review, construction inspection and post-construction maintenance process. Require submittal of BMP maintenance requirements. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Review all site plans. Provide annual training for reviewers and inspectors. Inspect post construction BMP’s. Milestones: By the end of permit year 5. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 10 of 21 6. Pollution Prevention/Good Housekeeping for Municipal Operations Does your MS4 presently have a program in place to promote pollution prevention and good housekeeping for municipal operations? Yes / No List municipally owned or operated facilities that would reasonably be expected to discharge contaminated runoff and are not covered under a NPDES permit: for example – vehicle maintenance garages, waste transfer operations, golf courses, salt or other materials storage, or open landfills. Also, indicate if there is a documented pollution prevention plan in place. Facility or type of facilities/operation: Pollution Prevention Plan? Regional Street Waste Facility Yes / No City shops Yes / No City Parks Yes / No Columbia Park golf course Yes / No Yes / No Minimum Measure Objective 6: Develop and implement a municipal O&M plan and training. BMP 6(a): Develop and implement a municipal O&M plan. Is this part of an existing program? Yes / No Is another entity involved in BMP implementation? Yes / No Measurable Goal: Develop and implement a municipal O&M plan addressing the following: 1. Park and open space maintenance pollution prevention/good housekeeping. 2. Vehicle and equipment washing. 3. Dust control practices. 4. Catch basin cleaning and storm water system maintenance pollution prevention/good housekeeping. 5. Structural storm water control pollution prevention/good housekeeping. 6. Deicing and snow removal pollution prevention/good housekeeping for roads and parking lots. 7. Flood management project evaluation and review procedures. 8. Employee training. Milestones: Development of plan by the end of permit year 3, implementation by the end of permit year 5. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 11 of 21 Part III. Recordkeeping and Reporting The permittee will comply with recordkeeping and reporting requirements per 40 CFR 122.34(g) Recordkeeping—40 CFR 122.34(g)(2) You must keep records required by the NPDES permit for at least three years. You must submit your records to the NPDES permitting authority only when specifically asked to do so. You must make your records, including a description of your stormwater management program, available to the public at reasonable times during regular business hours (see 122.7 for confidentiality provision). (You may assess a reasonable charge for copying. You may require a member of the public to provide advance notice.) Reporting—40 CFR 122.34(g)(3) Unless you are relying on another entity to satisfy your NPDES permit obligations under 122.35(a), you must submit annual reports in year two and four unless the NPDES permitting authority requires more frequent reports. Your report must include: The status of compliance with permit conditions, an assessment of the appropriateness of your identified best management practices and progress towards achieving your identified measurable goals for each of the minimum control measures; (ii) Results of information collected and analyzed, including monitoring data, if any, during the reporting period; (iii) A summary of the stormwater activities you plan to undertake during the next reporting cycle; (iv) A change in any identified best management practices or measurable goals for any of the minimum control measures; and Notice that you are relying on another governmental entity to satisfy some of your permit obligations (if applicable). Part IV. Certification I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. Authorized Representative Name: Robert R. Hammond, PE Title: Public Works Director Signature: Date: March 4, 2003 ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 12 of 21 APPENDIX I. Minimum Control Measure Requirements (source: 40 CFR 122.34(b)) 1. Public Education & Outreach on Stormwater Impacts Minimum Requirements – 40 CFR 122.34(b)(1)(i) You must implement a public education program to distribute educational materials to the community or conduct equivalent outreach activities about the impacts of stormwater discharges on water bodies and the steps that the public can take to reduce pollutants in stormwater runoff. Regulatory Guidance – 40 CFR 122.34(b)(1)(ii) You may use stormwater educational materials provided by your state; tribe; EPA; environmental, public interest, or trade organizations; or other MS4s. The public education program should inform individuals and households about the steps they can take to reduce stormwater pollution, such as ensuring proper septic system maintenance, ensuring the proper use and disposal of landscape and garden chemicals including fertilizers and pesticides, protecting and restoring riparian vegetation, and properly disposing of used motor oil and household hazardous wastes. EPA recommends that the program inform individuals and groups how to become involved in local stream and beach restoration activities, as well as activities that are coordinated by youth service and conservation corps or other citizen groups. EPA recommends that the public education program be tailored, using a mix of locally appropriate strategies, to target specific audiences and communities. Examples of strategies include distributing brochures or fact sheets, sponsoring speaking engagements before community groups, providing public service announcements, implementing educational programs targeted at school age children, and conducting community-based projects such as storm drain stenciling and watershed and beach cleanups. In addition, EPA recommends that some of the materials or outreach programs be directed toward targeted groups of commercial, industrial, and institutional entities likely to have significant stormwater impacts. For example, providing information to restaurants on the impact of grease clogging storm drains, and to garages on the impact of oil discharges. You are encouraged to tailor your outreach program to address the viewpoints and concerns of all communities, particularly minority and disadvantaged communities, as well as any special concerns relating to children. 2. Public Involvement/Participation Minimum Requirements – 40 CFR 122.34(b)(2)(i) You must, at a minimum, comply with state, tribal, and local public notice requirements when implementing a public involvement/participation program. Regulatory Guidance – 40 CFR 122.34(b)(2)(ii) EPA recommends that the public be included in developing, implementing, and reviewing your stormwater management program, and that the public participation process should make efforts to reach out and engage all economic and ethnic groups. Opportunities for members of the public to participate in program development and implementation include serving as citizen representatives on a local stormwater management panel, attending public hearings, working as citizen volunteers to educate other individuals about the program, assisting in program coordination with other pre-existing programs, or participating in volunteer monitoring efforts. (Citizens should obtain approval where necessary for lawful access to monitoring sites.) ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 13 of 21 3. Illicit Discharge Detection & Elimination Minimum Requirements – 40 CFR 122.34(b)(3)(i) You must develop, implement and enforce a program to detect and eliminate illicit discharges (as defined at Sec. 122.26(b)(2)) into your small MS4. (ii) You must: Develop, if not already completed, a storm sewer system map, showing the location of all outfalls and the names and location of all waters of the United States that receive discharges from those outfalls; To the extent allowable under State, Tribal or local law, effectively prohibit, through ordinance, or other regulatory mechanism, non-stormwater discharges into your storm sewer system and implement appropriate enforcement procedures and actions; Develop and implement a plan to detect and address non-stormwater discharges, including illegal dumping, to your system; and Inform public employees, businesses, and the general public of hazards associated with illegal discharges and improper disposal of waste. (iii) You need address the following categories of non-stormwater discharges or flows illicit discharges) only if you identify them as significant contributors of pollutants to your small MS4: water line flushing, landscape irrigation, diverted stream flows, rising ground waters, uncontaminated ground water infiltration (as defined at 40 CFR 35.2005(20)), uncontaminated pumped ground water, discharges from potable water sources, foundation drains, air conditioning condensation, irrigation water, springs, water from crawl space pumps, footing drains, lawn watering, individual residential car washing, flows from riparian habitats and wetlands, dechlorinated swimming pool discharges, and street wash water (discharges or flows from fire fighting activities are excluded from the effective prohibition against non-stormwater and need only be addressed where they are identified as significant sources of pollutants to waters of the United States). Regulatory Guidance – 40 CFR 122.34(b)(3)(iv) EPA recommends that the plan to detect and address illicit discharges include the following four components: procedures for locating priority areas likely to have illicit discharges; procedures for tracing the source of an illicit discharge; procedures for removing the source of the discharge; and procedures for program evaluation and assessment. EPA recommends visually screening outfalls during dry weather and conducting field tests of selected pollutants as part of the procedures for locating priority areas. Illicit discharge education actions may include storm drain stenciling; a program to promote, publicize, and facilitate public reporting of illicit connections or discharges; and distribution of outreach materials. 4. Construction Site Stormwater Runoff Control Minimum Requirements – 40 CFR 122.34(b)(4)(i) You must develop, implement, and enforce a program to reduce pollutants in any stormwater runoff to your small MS4 from construction activities that result in a land disturbance of greater than or equal to one acre. Reduction of stormwater discharges from construction activity disturbing less than one acre must be included in your program if that construction activity is part of a larger common plan of development or sale that would disturb one acre or more. If the NPDES permitting authority waives requirements for stormwater discharges associated with small construction activity in accordance with Sec. 122.26(b)(15)(i), you are not required to develop, implement, and/or enforce a program to reduce pollutant discharges from such sites. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 14 of 21 (ii) Your program must include the development and implementation of, at a minimum: An ordinance or other regulatory mechanism to require erosion and sediment controls, as well as sanctions to ensure compliance, to the extent allowable under State, Tribal, or local law; Requirements for construction site operators to implement appropriate erosion and sediment control (ESC) best management practices; Requirements for construction site operators to control waste such as discarded building materials, concrete truck washout, chemicals, litter, and sanitary waste at the construction site that may cause adverse impacts to water quality; Procedures for site plan review which incorporate consideration of potential water quality impacts; Procedures for receipt and consideration of information submitted by the public, and Procedures for site inspection and enforcement of control measures. Regulatory Guidance – 40 CFR 122.34(b)(4)(iii) Examples of sanctions to ensure compliance include non-monetary penalties, fines, bonding requirements, and/or permit denials for non-compliance. EPA recommends that procedures for site plan review include the review of individual pre-construction site plans to ensure consistency with local (ESC) requirements. Procedures for site inspections and enforcement of control measures could include steps to identify priority sites for inspection and enforcement based on the nature of the construction activity, topography, and the characteristics of soils and receiving water quality. You are encouraged to provide appropriate educational and training measures for construction site operators. You may wish to require a stormwater pollution prevention plan for construction sites within your jurisdiction that discharge into your system. See Sec. 122.44(s) (NPDES permitting authorities' option to incorporate qualifying State, Tribal and local erosion and sediment control programs into NPDES permits for stormwater discharges from construction sites). Also see Sec. 122.35(b) (The NPDES permitting authority may recognize that another government entity, including the permitting authority, may be responsible for implementing one or more of the minimum measures on your behalf). 5. Post-Construction Stormwater Management in New Development & Redevelopment Minimum Requirements – 40 CFR 122.34(b)(5)(i) You must develop, implement, and enforce a program to address stormwater runoff from new development and redevelopment projects that disturb greater than or equal to one acre, including projects less than one acre that are part of a larger common plan of development or sale, that discharge into your small MS4. Your program must ensure that controls are in place that would prevent or minimize water quality impacts. (ii) You must: Develop and implement strategies which include a combination of structural and/or non-structural best management practices (BMPs) appropriate for your community; Use an ordinance or other regulatory mechanism to address post-construction runoff from new development and redevelopment projects to the extent allowable under State, Tribal or local law; Ensure adequate long-term operation and maintenance of BMPs. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 15 of 21 Regulatory Guidance – 40 CFR 122.34(b)(5)(iii) If water quality impacts are considered from the beginning stages of a project, new development and potentially redevelopment provide more opportunities for water quality protection. EPA recommends that the BMPs chosen: be appropriate for the local community; minimize water quality impacts; and attempt to maintain pre- development runoff conditions. In choosing appropriate BMPs, EPA encourages you to participate in locally- based watershed planning efforts which attempt to involve a diverse group of stakeholders including interested citizens. When developing a program that is consistent with this measure's intent, EPA recommends that you adopt a planning process that identifies the municipality's program goals minimize water quality impacts resulting from post-construction runoff from new development and redevelopment), implementation strategies adopt a combination of structural and/or non-structural BMPs), operation and maintenance policies and procedures, and enforcement procedures. In developing your program, you should consider assessing existing ordinances, policies, programs and studies that address stormwater runoff quality. In addition to assessing these existing documents and programs, you should provide opportunities to the public to participate in the development of the program. Non-structural BMPs are preventative actions that involve management and source controls such as: policies and ordinances that provide requirements and standards to direct growth to identified areas, protect sensitive areas such as wetlands and riparian areas, maintain and/or increase open space (including a dedicated funding source for open space acquisition), provide buffers along sensitive water bodies, minimize impervious surfaces, and minimize disturbance of soils and vegetation; policies or ordinances that encourage infill development in higher density urban areas, and areas with existing infrastructure; education programs for developers and the public about project designs that minimize water quality impacts; and measures such as minimization of percent impervious area after development and minimization of directly connected impervious areas. Structural BMPs include: storage practices such as wet ponds and extended- detention outlet structures; filtration practices such as grassed swales, sand filters and filter strips; and infiltration practices such as infiltration basins and infiltration trenches. EPA recommends that you ensure the appropriate implementation of the structural BMPs by considering some or all of the following: pre- construction review of BMP designs; inspections during construction to verify BMPs are built as designed; post-construction inspection and maintenance of BMPs; and penalty provisions for the noncompliance with design, construction or operation and maintenance. Stormwater technologies are constantly being improved, and EPA recommends that your requirements be responsive to these changes, developments or improvements in control technologies. 6. Pollution Prevention/Good Housekeeping for Municipal Operations Minimum Requirements – 40 CFR 122.34(b)(6)(i) You must develop and implement an operation and maintenance program that includes a training component and has the ultimate goal of preventing or reducing pollutant runoff from municipal operations. Using training materials that are available from EPA, your state, Tribe, or other organizations, your program must include employee training to prevent and reduce stormwater pollution from activities such as park and open space maintenance, fleet and building maintenance, new construction and land disturbances, and stormwater system maintenance. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 16 of 21 Regulatory Guidance – 40 CFR 122.34(b)(6)(ii) EPA recommends that, at a minimum, you consider the following in developing your program: maintenance activities, maintenance schedules, and long-term inspection procedures for structural and nonstructural stormwater controls to reduce floatables and other pollutants discharged from your separate storm sewers; controls for reducing or eliminating the discharge of pollutants from streets, roads, highways, municipal parking lots, maintenance and storage yards, fleet or maintenance shops with outdoor storage areas, salt/sand storage locations and snow disposal areas operated by you, and waste transfer stations; procedures for properly disposing of waste removed from the separate storm sewers and areas listed above (such as dredge spoil, accumulated sediments, floatables, and other debris); and ways to ensure that new flood management projects assess the impacts on water quality and examine existing projects for incorporating additional water quality protection devices or practices. Operation and maintenance should be an integral component of all stormwater management programs. This measure is intended to improve the efficiency of these programs and require new programs where necessary. Properly developed and implemented operation and maintenance programs reduce the risk of water quality problems. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 17 of 21 APPENDIX II. ABBREVIATIONS*: BAT Best Available Technology Economically Achievable (applies to non-conventional and toxic pollutants) BCT Best Conventional Pollutant Control Technology (applies to conventional pollutants) BMP Best Management Practice BPJ Best Professional Judgment BPT Best Practicable Control Technology Currently Available (generally applies to conventional pollutants and some metals) CFR Code of Federal Regulations CGP Construction General Permit COD Chemical Oxygen Demand CSO Combined Sewer Overflow CWA Clean Water Act (formerly referred to as the Federal Water Pollution Control Act or Federal Water Pollution Control Act Amendments of 1972) CZARA Coastal Zone Act Reauthorization Amendments DO Dissolved Oxygen DMR Discharge Monitoring Report ELG Effluent Limitations Guidelines EPA Environmental Protection Agency FR Federal Register MEP Maximum Extent Practicable MS4 Municipal Separate Storm Sewer System MSGP Multi Sector General Permit NOI Notice of Intent NOT Notice of Termination NOV Notice of Violation NPDES National Pollutant Discharge Elimination System NPS Non-point Source O&M Operation and Maintenance OW Office of Water OWM Office of Wastewater Management PA Permitting Authority POTW Publicly Owned Treatment Works SIC Standard Industrial Classification Stormwater Pollution Prevention Plan TMDL Total Maximum Daily Load TSS Total Suspended Solids UA Urbanized Area DEFINITIONS*: Authorized Representative: For a municipality, State, Federal, or other public agency: By either a principal executive officer or ranking elected official. For purposes of this section, a principal executive officer of a Federal Agency includes the chief executive officer of the Agency, or (ii) a senior executive officer having responsibility for the overall operations of a principal geographic unit of the Agency Regional Administrators of EPA). All reports required by permits, and or other information requested by the Director shall be signed by a person described in paragraph of this section, or by a duly authorized representative of that person. Best Available Treatment(BAT)/Best Control Technology (BCT): A level of technology based on the very best (state of the art) control and treatment measures that have been developed or are capable of being developed and that are economically achievable within the appropriate industrial category. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 18 of 21 Best Management Practices (BMPs): Activities or structural improvements that help reduce the quantity and improve the quality of stormwater runoff. BMPs include treatment requirements, operating procedures, and practices to control site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw material storage. Category (xi) facilities: Specific facilities classified as light industry with equipment or materials exposed to stormwater. Clean Water Act (Water Quality Act): (formerly the Federal Water Pollution Control Act or Federal Water Pollution Control Act Amendments of 1972). Public law 92-500; 33 U.S.C. 1251 et seq.; legislation which provides statutory authority for the NPDES program. Also know as the Federal Water Pollution Control Act. Conveyance: The process of water moving from one place to another. Detention Facility: An above or below ground facility, such as a pond or tank, that temporarily stores stormwater runoff and subsequently releases it at a slower rate than it is collected by the drainage facility system. There is little or no infiltration of stored stormwater. Discharge: The volume of water (and suspended sediment if surface water) that passes a given location within a given period of time. Erosion: When land is diminished or worn away due to wind, water, or glacial ice. Often the eroded debris (silt or sediment) becomes a pollutant via stormwater runoff. Erosion occurs naturally but can be intensified by land clearing activities such as farming, development, road-building, and timber harvesting. Excavation: The process of removing earth, stone, or other materials from land. General Permit: A permit issued under the NPDES program to cover a certain class or category of stormwater discharges. These permits reduce the administrative burden of permitting stormwater discharges. Grading: The cutting and/or filling of the land surface to a desired slope or elevation. Illicit Connection: Any discharge to a municipal separate storm sewer that is not composed entirely of stormwater and is not authorized by an NPDES permit, with some exceptions discharges due to fire fighting activities). Interconnected: See Physically Interconnected Industrial Activity: Any activity which is directly related to manufacturing, processing or raw materials storage areas at an industrial plant. Large Municipal Separate Storm Sewer System (MS4): An MS4 located in an incorporated place or county with a population of 250,000 or more, as determined by Light Manufacturing Facilities: Described under Category (xi) of the definition of “stormwater discharges associated with industrial activity” [CFR 122 26(b)(14)(i-ix and xi)]. Under the Phase I NPDES Stormwater Program, these facilities were eligible for exemption from stormwater permitting requirements if certain areas and activities were not exposed to stormwater. As a result of the Phase II Final Rule, these facilities must now certify to a condition of no exposure. Low Impact Development: The integration of site ecological and environmental goal and requirements into all phases of urban planning and design from the individual residential lot level to the entire watershed. Hydrologic functions of storage, infiltration, and ground water recharge, as well as the volume and frequency of discharges are maintained through the use of integrated and distributed micro-scale stormwater retention and detention areas, reduction of impervious surfaces, and the lengthening of flow paths and runoff time. Other strategies include the preservation/protection of environmentally sensitive site features such as riparian buffers, wetlands, steep slopes, valuable (mature) trees, flood plains, woodland and highly permeable soils. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 19 of 21 Maximum Extent Practicable (MEP): A standard for water quality that applies to all MS4 operators regulated under the NPDES Stormwater Program. Since no precise definition of MEP exists, it allows for maximum flexibility on the part of MS4 operators as they develop and implement their programs. Medium Municipal Separate Storm Sewer System (MS4): MS4 located in an incorporated place or county with a population of 100,000 or more but less than 250,000, as determined by the latest U.S. Census. Municipal Separate Storm Sewer System (MS4): A publicly -owned conveyance or system of conveyances that discharges to waters of the U.S. and is designed or used for collecting or conveying stormwater, is not a combined sewer, and is not part of a publicly-owned treatment works (POTW). Multi-Sector General Permit (MSGP): An NPDES permit that regulates stormwater discharges from eleven categories of industrial activities. New Development: Land disturbing activities, including Class IV - general forest practices that are conversions from timber land to other uses; structural development, including construction or installation of a building or other structure; creation of impervious surfaces; and subdivision, short subdivision and binding site plans, as defined and applied in Chapter 58.17 RCW. Projects meeting the definition of redevelopment shall not be considered new development. No exposure: All industrial materials or activities are protected by a storm resistant shelter to prevent exposure to rain, snow, snowmelt, and/or runoff. Industrial materials or activities include, but are not limited to, material handling equipment or activities, industrial machinery, raw materials, intermediate products, by-products, final products, or waste products. Material handling activities include the storage, loading and unloading, transportation, or conveyance of any raw material, intermediate product, final product or waste product. Non-authorized States: any State that does not have the authority to regulate the NPDES Stormwater Program. Non-point Source (NPS) Pollutants: Pollutants from many diffuse sources. NPS pollution is caused by rainfall or snowmelt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants, finally depositing them into lakes, rivers, wetlands, coastal waters, and even our underground sources of drinking water. Notice of Intent (NOI): An application to notify the permitting authority of a facility’s intention to be covered by a general permit; exempts a facility from having to submit an individual or group application. NPDES: “National Pollutant Discharge Elimination System” the name of the surface water quality program authorized by Congress as part of the 1987 Clean Water Act. This is EPA program to control the discharge of pollutants to waters of the United States (see 40 CFR 122.2). O&M Expenditures: The operating and maintenance costs associated with the continual workings of a project. Outfall: The point where wastewater or drainage discharges from a sewer pipe, ditch, or other conveyance to a receiving body of water. Permitting Authority (PA): The NPDES-authorized state agency or EPA regional office that administers the NPDES Stormwater Program. PAs issue permits, provide compliance assistance, and inspect and enforce the program. Physically interconnected MS4: This means that one MS4 is connected to a second MS4 in such a way that it allows for direct discharges into the second system. Point Source Pollutant: Pollutants from a single, identifiable source such as a factory or refinery. Pollutant Loading: The total quantity of pollutants in stormwater runoff. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 20 of 21 Qualifying local program: A local, State or Tribal municipal stormwater management program that imposes, at a minimum, the relevant requirements of one or more of the minimum control measures includes in 122.34(b). Redevelopment: On a site that is already substantially developed has more than 35% or more of existing impervious surface coverage), the creation or addition of impervious surfaces; the expansion of a building footprint or addition or replacement of a structure; structural development including construction, installation or expansion of a building or other structure; replacement of impervious surface that is not part of a routine maintenance activity; and land disturbing activities. Regional: An action (here, for stormwater management purposes) that involves more than one discrete property. Regional Detention Facility: A stormwater quantity control structure designed to correct the existing surface water runoff problems of a basin or subbasin. The area has been previously identified as having existing or predicted significant and regional flooding and/or erosion problems. This term is also used when a detention facility is sited to detain stormwater runoff from a number of new developments or areas within a catchment Regulated MS4: Any MS4 covered by the NPDES Stormwater Program (regulated small, medium, or large MS4s). Retention: The process of collecting and holding surface and stormwater runoff with no surface outflow. Retention/detention facility A type of drainage facility designed either to hold water for a considerable length of time and then release it by evaporation, plant transpiration, and/or infiltration into the ground; or to hold surface and stormwater runoff for a sort period of time and then release it to the surface and stormwater management system. Retrofit: The modification of stormwater management systems through the construction and/or enhancement of wet ponds, wetland plantings, or other BMPs designed to improve water quality Runoff: Drainage or flood discharge that leaves an area as surface flow or as pipeline flow. Has reached a channel or pipeline by either surface or sub-surface routes. Sanitary Sewer: A system of underground pipes that carries sanitary waste or process wastewater to a treatment plant. Sediment: Soil, sand, and minerals washed from land into water, usually after rain. Sediment can destroy fish- nesting areas, clog animal habitats, and cloud waters so that sunlight does not reach aquatic plants. Sheet flow: The portion of precipitation that moves initially as overland flow in very shallow depths before eventually reaching a stream channel. Site Plan: A graphical representation of a layout of buildings and facilities on a parcel of land. Site Runoff: Any drainage or flood discharge that is released from a specified area. Small Municipal Separate Storm Sewer System (MS4): Any MS4 that is not regulated under Phase I of the NIPDES Stormwater Program and Federally-owned MS4s. Stakeholder: An entity that holds a special interest in an issue or program such as the stormwater program - since it is or may be affected by it. Standard Industrial Classification (SIC) Code: A four digit number which is used to identify various types of industries. Storm Drain: A slotted opening leading to an underground pipe or an open ditch for carrying surface runoff. ---PAGE BREAK--- 10/15/02 Please submit before March 10, 2003 Page 21 of 21 Stormwater: Precipitation that accumulates in natural and/or constructed storage and stormwater systems during and immediately following a storm event. Stormwater Management: Functions associated with planning, designing, constructing, maintaining, financing, and regulating the facilities (both constructed and natural) that collect, store, control, and/or convey stormwater. Stormwater Pollution Prevention Plan A plan to describe a process whereby a facility thoroughly evaluates potential pollutant sources at a site and selects and implements appropriate measures designed to prevent or control the discharge of pollutants in stormwater runoff. Surface Water: Water that remains on the surface of the ground, including rivers, lakes, reservoirs, streams, wetlands, impoundments, seas, estuaries, etc. Total Maximum Daily Load (TMDL): The maximum amount of pollutants which can released into a water body without adversely affecting the water quality. Tool Box: A term to describe the activities and materials that EPA plans to perform/produce to facilitate implementation of the stormwater program in an effective and cost-efficient manner. The eight components include: 1) fact sheets; 2) guidance documents; 3) menu of BMPs; 4) compliance assistance; 5) information clearing house; 6) training and outreach efforts; 7) technical research; and 8) support for demonstration projects. Treatment BMP: A BMP that is intended to remove pollutants form stormwater. A few examples of treatment BMPs are detention ponds, oil/water separators, biofiltration swales, and constructed wetlands. Uncontrolled Sanitary Landfill: a landfill or open dump, whether in operation or closed, that does not meet the requirements for run-on or runoff controls established pursuant to subtitle D of the Solid Waste Disposal Act. Urbanized Area (UA): A Bureau of the Census determination of a central place (or places) and the adjacent densely settled surrounding territory that together have a minimum residential population of 50,000 people and a minimum average density of 1,000 people/square mile. This is a simplified definition of a UA; the full definition is very complex. Urban Growth Areas means those areas designated by a county pursuant to RCW 36.70A.110. Urban Runoff: Stormwater from urban areas, which tends to contain heavy concentrations of pollutants from urban activities. Watershed: That geographical area which drains to a specified point on a water course, usually a confluence of streams or rivers (also known as drainage area, catchment, or river basin). Wet Weather Flows: Water entering storm drains during rainstorms/wet weather events. *The following references were used in these sections: • Stormwater Phase II Compliance Assistance Guide; United States Environmental Protection Agency, Office of Water; March 2000; Publication # EPA 833-R-00-002. • 40 Code of Federal Regulations, part 122.22, United States Environmental Protection Agency. • Stormwater Management Manual for Western Washington; Washington State Department of Ecology; August 2001; Publication # 99-11 through 99-13. • Low Impact Development in Puget Sound; Innovative Stormwater Management Practices, a conference sponsored by the Puget Sound Water Quality Action Team and King County Department of Natural Resources through a Water Works Grant. • Low Impact Development Design Strategies, An Integrated Design Approach; Prince Georges County, Maryland, Department of Environmental Resources; June 1999. ---PAGE BREAK--- ---PAGE BREAK--- Appendix F — Stormwater Program Analysis Questionnaire: City's Response ---PAGE BREAK--- ---PAGE BREAK--- K:\project\30300\30386\Reports\Final Report\Appendices\Appendix F - 020404_Questionnaire.doc M e m o r a n d u m To: City of Kennewick and HDR From: Laura Becker for Joe Simmler Copies: Date: January 27, 2004 Subject: Regulatory Compliance Questionnaire 620 Kirkland Way, #100 Kirkland, WA 98033 Phone (425) 822-4446 Fax (425) 827-9577 Project 30386 Abbreviations: City City of Kennewick SWM Storm Water Management BMPs Best Management Practices EWSMM Eastern Washington Stormwater Management Manual O&M Operation and Maintenance UIC Underground Injection Control 1. Does the City of Kennewick (City) perform a self-analysis of their existing Storm Water Management (SWM) Program? We have made minor modifications to our program since implementation. However, this is the first detailed analysis. 2. Has the City identified any local compliance needs? That is one of our goals from this process. 3. Has the City identified any associated costs, space equipment, and funding needs? That is one of our goals from this process. 4. Has the City developed a SWM Action Plan/Schedule? That is one of our goals from this process. 5. Does the City feel any interlocal agreements are needed? That is one of our goals from this process. 6. Has the City identified any local sources of funding? That is one of our goals from this process. 7. Does the City have a stormwater education and outreach strategy? No. 8. Has the City developed and/or distributed any public education and involvement brochures? No. 9. Has the City developed and/or distributed any targeted stormwater brochures? No. ---PAGE BREAK--- City of Kennewick Page 2 Regulatory Compliance Questionnaire January 27, 2004 K:\project\30300\30386\Reports\Final Report\Appendices\Appendix F - 020404_Questionnaire.doc 10. Has the City done storm drain stenciling? No. 11. Has the City contacted the school districts to discuss opportunities to provide water quality educational materials? No. 12. Has the City provided water quality educational materials when requested? No. 13. Has the City contacted volunteer organizations to discuss opportunities to integrate stormwater into existing education projects? No. 14. Is there a stormwater speakers' bureau? No. 15. Does the City broadcast stormwater public service announcements in the media? No. 16. Does the City display stormwater exhibits at community locations? No. 17. Does the City have a stormwater web site? No. 18. Does the City hold public meetings to solicit public input? No. 19. Does the City create stormwater news releases? No. 20. Is there a stakeholder advisory panel? No. 21. Does the stakeholder advisory panel provide input to the City? No. 22. How does the City respond to calls from the public? Calls are all related to flooding issues. We have a rating system for prioritizing these complaints. 23. Does the City have a storm sewer outfall map? Yes. 24. Is there a City ordinance prohibiting illicit discharges on private property? Yes. 25. How is the ordinance enforced? Nuisance law and code enforcement. 26. Does the City have an illicit discharge detection plan? No. 27. Does the City have a spill response plan? Yes. 28. What is the City’s enforcement plan? Legal action. 29. Does the City inspect known outfalls? No. ---PAGE BREAK--- City of Kennewick Page 3 Regulatory Compliance Questionnaire January 27, 2004 K:\project\30300\30386\Reports\Final Report\Appendices\Appendix F - 020404_Questionnaire.doc 30. Does the City provide training to educate staff on Best Management Practices (BMPs) for spills and illicit discharges? No – coordinated through our Environmental Engineer. 31. Does the City have an ordinance for permits for erosion and sediments control? No. 32. Does the City provide training to educate plan reviewers and inspectors in erosion and sediment control BMPs? No. 33. Does the City review site plans prior to construction to ensure compliance with local ordinances? Yes. 34. Does the City have a system for receiving public input on construction site runoff issues? No. 35. Is public input passed on to field inspectors? Yes. 36. Does the City inspect all construction sites that are regulated by? Yes. 37. Does the City provide construction operators with information on local BMP training opportunities? No. 38. The Eastern Washington Stormwater Management Manual (EWSMM) requires permits for construction operators. Does the City have an ordinance for permits for construction operators? No. 39. What is the City’s plan for addressing post-construction stormwater runoff? See City of Kennewick Standard Specification 7-10 (available on our web site). 40. Does the City provide BMP training for construction plan reviewers and field inspectors? No. 41. Do City reviewers consider post-construction runoff compliance when reviewing site plans? Post construction runoff is our only requirement. 42. Does the City inspect BMPs during construction to ensure compliance? No. 43. Does the City have a Municipal Operation and Maintenance (O&M) Plan? We have portions of one. 44. Are park and open space O&M practices implemented per the O&M Plan? O&M practices are not defined by a written plan. 45. Are publicly owned vehicle and equipment washing practices per the O&M Plan? 46. Are dust control practices implemented per the O&M Plan? Dust control is monitored by the Benton County Clean Air Authority. ---PAGE BREAK--- City of Kennewick Page 4 Regulatory Compliance Questionnaire January 27, 2004 K:\project\30300\30386\Reports\Final Report\Appendices\Appendix F - 020404_Questionnaire.doc 46. Is catch basin cleaning and system O&M implemented per the O&M Plan? Yes. 47. Are structural O&M practices implemented per the O&M Plan? Both sanitary and storm sewers are video inspected. 48. Are deicing and snow removal O&M practices implemented per the O&M Plan? Yes. 49. Are flood management project evaluation and review procedures implemented per the O&M Plan? See existing storm plan. See #22. 50. Does the City provide O&M training for City employees? Yes. 52. Is there a pollution management plan for all municipal facilities? No. 53. Are industrial (stormwater) permit applications submitted as needed? Yes. 54. What is the City’s O&M waste disposal procedure? Wastes are characterized first, then taken to the appropriate facility. 55. Does the City anticipate any major upcoming O&M equipment purchases? New front end loader to assist with solid waste handling. 56. What is the City’s street sweeping procedure? Residential streets are swept quarterly, arterials every 3 weeks. 57. How does the City manage permitting? Through the Environmental Engineer and the M&O Manager. 58. How does the City track permitting? Through the appropriate manager. 59. How does the City report permitting? Through the appropriate manager and as required by the permit (annually at a minimum). 60. Are publicly owned infiltration facilities located and mapped? Yes. 61. Does the City have a regional risk based strategy for application of future stormwater infiltration systems (based on soils, groundwater, drinking water wells, etc)? No. 62. Has the City identified existing publicly owned infiltration systems in areas of high risk for groundwater degradation? Yes, within our wellhead protection area 3 year time of travel. 63. Does the City have a written plan for the management and/or replacement strategy that will reduce pollutant loading to groundwater in high-risk areas? Yes. 64. What is the City’s management strategy for the high-risk systems? As defined in our wellhead protection plan. ---PAGE BREAK--- City of Kennewick Page 5 Regulatory Compliance Questionnaire January 27, 2004 K:\project\30300\30386\Reports\Final Report\Appendices\Appendix F - 020404_Questionnaire.doc 65. Does that strategy include monitoring, effectiveness assessment, report preparation, enhanced O&M, source control, spill control/response, opportunistic retrofits? N/A 66. Does the City train employees to manage high-risk systems? Yes. 67. Has the City located and registered publicly owned infiltration systems? No. 68. How does the City enforce construction standards (drywells and pretreatment)? The public works department inspects storm drainage facilities. Publicly owned facilities are constructed to City standards. Private facilities are inspected to ensure compliance with the approved design. Pretreatment is not a current requirement. 69. Do public systems receive annual maintenance after construction is complete? Yes. 70. What is the City’s pollution prevention plan for public infiltration systems? N/A 71. Is the area draining to drywells documented by land use? No. 72. Does the City review and revise legal ordinances? Yes. 73. Is there a regional interlocal agreement for Underground Injection Control (UIC)? No. 74. Does the City provide UIC training for staff? No. 75. Are there design standards for locating and constructing infiltration facilities? Construction yes, locating no. 76. Does the City report to the Department of Ecology regularly? Yes. As required by our waste discharge permit for the wastewater treatment plant and as required by construction storm water permits 77. Does the City assess stormwater impacts when making land use decisions? No. 78. Does the City try to reduce stormwater runoff, reduce impervious surfaces, and retain native vegetation? No. 79. Does the City have standards equivalent to the DOE manual? No. 80. Does the City have source control standards equivalent to DOE? See KMC 14.22 and 14.28 attached. 81. Does the City participate in interagency surface water quality strategy coordination? No. 82. Does the City actively participate in the development of for receiving waters? N/A 83. Does the City monitor the outfall quality of discharges to impaired waters? No. ---PAGE BREAK--- City of Kennewick Page 6 Regulatory Compliance Questionnaire January 27, 2004 K:\project\30300\30386\Reports\Final Report\Appendices\Appendix F - 020404_Questionnaire.doc 84. Are stormwater outfalls allocated a load in TMDL? No. 85. Is there a regional program to monitor baseline conditions and evaluate surface water program effectiveness? No. ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling ---PAGE BREAK--- ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-1 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc Introduction to Modeling A hydrological and hydraulic model (H&H model) of the City of Kennewick’s stormwater collection system was constructed to aid in the assessment of hydraulic capacity limited portions of their system. The focus of the model is on problem areas that are currently prone to flooding and other areas that may be prone to flooding in the future. The H&H model was created using geographic information system (GIS) mapping generated from CAD and stormwater system inventory information obtained from the City of Kennewick. Hyetographs and standards from the Department of Ecology’s Stormwater Management Manual for Eastern Washington, September 2004 were used to predict stormwater runoff from the modeled area for the 25- and 100-year storm events. Runoff from these events was used to identify hydraulic capacity limited portions of the stormwater collection system, and then compared to areas of known flooding as identified by City staff. A future condition scenario was also modeled to assess surcharge areas due to full build-out of the existing UGA and develop recommendations for improvements required to reduce potential surcharge. Hydrological and Hydraulic Model Construction This section describes the process used to develop and construct an H&H model by integrating data from the system inventory GIS database and the computer- modeling application. Model Selection and Overview A comprehensive computer model was used for analysis of the City’s urban stormwater runoff quantity and stormwater collection system. HYDRA® 6.3, Pizer International, Seattle WA, was used to accomplish this by simulating hydrological and hydraulic processes on pervious and impervious land surfaces, drainage ways, streams, and conduits. The development of HYDRA originally began in the late 1960’s as mainframe timeshare computers became available and the need to analyze large stormwater systems more quickly was desired. Maintenance and improvements of the software led to release of the version that can be used today with Windows®. The predominant historical use of HYDRA is the modeling of wastewater and/or hydrological and hydraulic analyses for urban systems. Prediction of flows and stages can be performed on catchments having a drainage network consisting of piping systems, combination systems with wastewater, and natural drainage ways. HYDRA can be used to simulate rainfall, surface runoff, and ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-2 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc percolation capacity due to subsurface conditions. It can also be used to analyze existing system capacity, determine system capacity upgrades, size system components, and determine capital costs of system upgrades. The current model considers only the drainage area within the city limits of Kennewick and its current Urban Growth Area (UGA) limits. The size of the HYDRA model is essentially limitless with the limiting factor being the size of data one wishes to management during a single analysis iteration or the hardware system used to operate the model. Naturally, the larger the model, the longer it takes to generate results. Currently, the entire stormwater collection system for the City is set up as one model. This is dependant upon capacity and speed of the computer system used to generate results. Data requirements for hydrologic simulations include surface area, portion impervious, slope, surface conditions, soil and subsurface characteristics related to permeability, and rainfall intensity-duration-frequency information. The City of Kennewick chose HYDRA as their modeling software to analyze their stormwater collection system in an effort to combine modeling expertise from their developed sanitary sewer model, also completed using HYDRA. HDR supplemented the model development through the use of ArcGIS 9.0, a GIS application software used to process and develop an electronic information database for the City’s storm drainage assets. The electronic framework for the City’s infrastructure was developed in ArcGIS and then transferred into HYDRA for analysis and computation. The results of the model were transferred back into ArcGIS to create the visual products and maintain the storm database. Model Components HYDRA requires several key elements to operate: a collection system consisting of nodes and links, a drainage area consisting of basins, and stormwater input consisting of hyetographs reflecting local conditions. The following is a more detailed description of the key elements. Although there are many other attributes that each element can include, the key ones used for this analysis are listed below. Node: These represent the connection point of all links within the collection network system, including the terminus upstream and end of all runs. Attributes include the following: • Node ID • X Coordinate • Y Coordinate ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-3 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc • Node Type: (Although there are other types allowed, the following are the main ones utilized in the model) - MAN (Manholes): This includes catch basins, and general connection points for links - OUT (Outfalls): This is require at the terminus end of all runs - RES (Reservoirs): These model drywells and retention basins and could be used to connect links as well. They consist of stage/ storage and discharge parameters. Several drywells could be modeled by one node by modifying the stage/storage parameters. • Ground Elevation • Invert Elevation • Size (diameter of MAN or volume of RES) • Upstream Link(s) ID connecting to node • Link ID connecting to node • Exfiltration Rates (soil percolation for RES. The rate could be adjusted to account for a number of drywells in a drainage basin as well) Link: These represent existing pipes, culverts, overland flow, drainage ways, and open channels. Attributes include the following: • Link ID • Link Type: (Although there are other types allowed, the following are the main ones utilized in the model) - Pipes - Culverts - Overland flow - Open channels (Various configurations are typified for various conditions such as ditches, canals, stream areas, etc) • Characteristics for Existing Pipe and Culverts: - Velocity parameters - Roughness (per conduit type) - Diameter ratio - Entrance characteristics (culverts) - Exfiltration (if necessary) • Design Characteristics for Overland Flow, drainage ways, and Open Channels: - Velocity parameters - Roughness - Side slopes - Bottom width - Depth ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-4 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc • Length • Upstream ground elevation • ground elevation • Upstream Invert Elevation • Invert Elevation • Diameter (pipes or culverts) • Upstream Node ID • Node ID Basins: These represent sub-catchments that receive stormwater runoff that is integrated into the collection system model. This is done so by assignment to a node that represents the point of injection. Attributes include the following: • Basin ID • Area • Percent Impervious • Slope • Time of Concentration (Tc) • Injection Node (Connection point for runoff into collection system model) Stormwater Hydrographs: Hydrographs were developed for local rainfall conditions of the 24-hour SCS Type IA storm for both the 25-year and 100-year events based upon criteria of the Stormwater Management Manual for Eastern Washington. Each hyetograph was set up in 30-minute increments using hydrographic storm criteria within HYDRA and are represented as “FLO” files. 24-hour rainfall is 1.6 in for the 25-year storm event and 2.0 in for the 100-year storm event. Model Input Data – System Inventory A system inventory GIS database has been collected by the City of Kennewick. This database was used as the basis for developing the H&H model. The system inventory includes spatial documentation of the physical features of the stormwater system, including pipes, culverts, open channels, manholes, drywells, and catch basins. The inventory utilized data extracted from the City of Kennewick’s library of AutoCAD drawings to the maximum extent possible. The City’s AutoCAD files contained types of pipe, diameters, and locations for the publicly owned pipes, culverts, ditches, and structures throughout the City’s stormwater collection system. Using ArcGIS 9.0 software and the AutoCAD spatial information provided by the City, a single system inventory database was created. The system inventory ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-5 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc database, including information that was assumed, was then used as input into HYDRA for analysis. Model Data Pre-Processing Areas within the model did not contain all of the necessary information needed to produce a complete model (i.e. pipe invert elevation). When the data necessary to construct a complete H&H model, a typical value was assumed and entered in the GIS database layer. The assumed information can easily be replaced in the system inventory GIS database as new information becomes available during routine maintenance activities and missing data is entered. Typical information that was required is some cases include pipe size, invert elevations, manhole depths, rim elevations, and pipe type. Data assumptions are identified in comment fields in the GIS database. Details of the modifications are summarized below. The H&H model addressed the mainline pipes and routes of the stormwater collection system only. Branches of the conveyance network without a defined upstream sub-catchment were not included in the H&H model. Therefore, the model is used to determine and analysis the major conveyance routes of stormwater within the City. Areas of localized flooding due to inlet capacity and local infrastructure issues may not be addressed in the model. The model’s focus is on stormwater mainlines and drainage way capacity to handle the existing and future growth within the City. Nodes Each of the nodes in the system inventory has been assigned an identification number via HYDRA that correlates to the GIS database files. There are 1345 nodes in the existing conditions system model, with an additional 15 in the future conditions system model. The type of each node was defined as listed under Model Components above. Model nodes were located in GIS mapping as they corresponded to existing storm drainage system features, such as manholes or drywells. Ground Elevations: These were assigned to each of the nodes using aerial digital topography, provided by the City of Kennewick’s GIS department, supplemented by a USGS 10-Meter Digital Elevation Model for holes within the City provided data and areas outside the current city boundary. Invert Elevation and Manhole Diameter: These were assigned to those nodes that had a record of either manhole depth or diameter. If data was not provided, then an estimate was assigned. If a link resulted in a reverse slope, ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-6 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc then the node depth was adjusted accordingly to allow the link slope to mimic the ground slope above it. Manholes: depth of 6’ and diameter of 4’ Drywell: depth of 15’ and diameter of 6’ Retentions Basins: Nodes were used to model retention basins. The definition for each retention basin was set up specifically within HYDRA on a case by case basis with data collected from the City or through field observation Drywells: To model drywells within a sub-basin, ArcGIS was used to populate a field counting the number of City-identified drywells within a given sub-basin. Based on infiltration data, a composite set of stage/storage and discharge parameters were calculated a defined within HYDRA to estimate the impact of all of the drywells within the sub-basin at a single node. This node corresponds to the inlet node for the sub-basin. Therefore, the impact of multiple drywells within the sub-basin would have a direct effect on the inflow into the system model at the same location. This method was developed in coordination with Pizer, Inc. and believed to be the most accurate and efficient way to model the City of Kennewick’s numerous public drywells. Links Each of the links in the system inventory has been assigned an identification number that correlates to the GIS database files. There are approximately 1300 links in the existing conditions system model, with 10 additional in the future conditions system model. The links consist of pipes, culverts, overland flows, gutter flows, and open channel flows. The collection system model was constructed by connecting each link to a corresponding upstream or link(s) using the nodes. Links representing pipes and culverts were positioned in the same location as the CAD file entities provided by the City. Links representing overland, gutter, and open channel flows were manually added in approximated positions to complete the routing network used to model flow routes. The following describes how additional information was addressed for each link. Pipe and Culvert Type: Type of each pipe or culvert was assigned using system inventory and original CAD mapping of the inventory provided by the City and imported into GIS. If a type of material for pipes or culverts ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-7 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc was not listed, it was assumed to be concrete or corrugated metal pipe respectively. The type for culverts in some cases was identified per field observation. Pipe roughness was then associated for each type of pipe or culvert within specific defined parameters within HYDRA. Diameter: Diameters of each pipe or culvert link were assigned using system inventory and original CAD mapping of the inventory provided by the City and imported into GIS. When missing, these values were assigned the size of the smallest adjacent pipe link to it or 12 inches if no size was provided. During initial analyses, pipe sizes associated with potential problem areas were confirmed with City staff, adjusted as needed, and re-analyzed. Open Channels: No information was provided by the City for “Open Channel” links. Therefore, the geometry, depth, and channel roughness were assigned based upon field observations. A variety of typical channel sections were define within HYDRA for various type channels such as gutter, ditch, and drainage ways of various average shapes. Length: The length of all links was calculated based upon the physical position of the link in GIS mapping. Ground Elevation: These were obtained from the ground elevation of the node attached to the end point of the link. Invert Elevation and Slope: When inverts were not provided, then they were estimated based on the attributes of the adjacent link and/or node. Generally, invert elevations of the pipe was assigned such that the slope of the pipe matched the slope of the ground above it. If the link were a gutter, then the invert elevations would match the ground elevation. Basins As described in Section 3, the City is divided into 17 major drainage basins. Drainage sub-basins for each of these major basins were delineated using a combination of aerial topography and previous delineations provided by the City. Subbasins were further delineated to account for future conditions without adding additional basins. Approximately 970 sub-basins were modeled ranging from approximately 3 to 600 acres. The basins are used to calculate runoff and estimate the stormwater flow that enters the drainage collection network. ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-8 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc The aerial topography provided by the City of Kennewick was used in developing the average basin slope. Analysis of these maps in GIS was conducted to delineate basin and sub-basin boundaries, determine watercourse alignments and tributary flow paths, measure sub-basin geometric properties, estimate routing parameters for open channels, and calculate basin time lag parameters. Land Use A second model scenario looked at the 20-year build-out for the City of Kennewick. In order to look forward with the model, the sub-basins were analyzed in conjunction with the comprehensive zoning map for areas of potential growth. Potential growth was determined by comparing existing developed conditions reflected in the existing system analysis to the buildable areas remaining within the UGA. Based on the amount of buildable area remaining in each sub-basin and imperviousness percentage estimates for the comprehensive zoning, new amounts of imperviousness were estimated and a new CN value was calculated for the future sub-basins in the model analysis. Figures showing land use assumptions for both existing and future conditions are provided in Section 7. Stormwater Runoff Stormwater Runoff within each sub-basin was developed based upon the parameters described as follows. Curve Numbers: The runoff curve numbers (CN) were developed from a composite GIS layer created for both current and future land use conditions. The composite GIS layers were prepared by creating a cross-reference matrix and performing a two-layer GIS analysis of the soils and land use coverages. Essentially, the results of the intersection of the SSURGO soils GIS layer, which was obtained from the NRCS with the land use GIS data layers, were cross-referenced to the curve number table and underlying hydrologic soil type per the Stormwater Management Manual for Eastern Washington to determine the curve number. Each relative contribution of these parameters was then averaged within each of the sub-basins and assigned to it for both existing and future conditions. Impervious Area: The extent of impervious surfaces within each sub-basin is an important factor in determining runoff. Percent impervious values were assigned for each land use classification based upon guidelines outlined in the Stormwater Management Manual for Eastern Washington. Subsequently, each grid cell (5-foot resolution) in the GIS database was assigned a percent ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-9 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc impervious value. Average impervious values were then calculated for each sub-basin for existing and future conditions based upon all of the grid cell values in the sub-basin. Time of Concentration (Tc): Time of Concentration (Tc) was calculated using the TR-55 method (shallow flow, sheet flow and channel flow). Lag Time: The lag time approach was used to transform the excess precipitation into peak flow, volume, and timing of stream flow at the sub- basin outlets. Basin lag time, which represents an estimate of the response time between the centroid of effective precipitation and the time of peak of the runoff hydrograph, was calculated for each sub-basin using a cumulative time of concentration for sheet flow, shallow flow and channel flow based upon the standard SCS TR-55 methodology. The SCS methodology assumes that lag time may be calculated as six tenths of the time of concentration, which represents an estimate of the time from the end of excess rainfall until the inflection point on the recession curve of the hydrograph. Readers are directed to (HEC, 1999) for a more complete description of the TR-55 methodology. Hydrographs were developed for local rainfall conditions of the 24-hour SCS Type IA storm for both the 25-year and 100-year events, based upon criteria of the SWMM for Eastern Washington. Under Region 2 (Central Basin), it’s recommended that the SCS Type 1A Hyetograph for long duration storm events be used for storm water runoff evaluation. These storm events would be characterized as occurring typically in the winter and spring season in the Mid-Columbia. The manual suggests a separate hyetograph for the short duration high intensity storm that Kennewick typically experiences during the summer and fall seasons. For analysis of the Comprehensive Plan, the long duration storm event was modeled. An example rainfall intensity for these events is shown in Figure 1. Each hyetograph was set up in 30-minute increments within HYDRA. 24-hour rainfall is 1.6 inches for the 25-year storm event and 2.0 inches for the 100-year storm event. If required, the short duration storm event can also be modeled for specific areas throughout the City to see the specific effects on the storm drainage system. ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-10 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc Figure 1 — Hydrograph 25-Year The locations where runoff from the basins, or sub-catchments, enters the conveyance system were defined by adding the identification of each corresponding node as an attribute to each sub-catchment. The “inlet” node for each sub-catchment was generally selected near the middle to upper portion of the basin. The estimated runoff from the 25-year 24-hour storm event was used for predicting areas of surcharge. The 100-year 24-hour storm event analyzed additional areas of concern the City may choose to address as well. Irrigation Canals The model assumes that existing discharges will be maintained into existing irrigation canals. There are numerous locations across the City’s UGA where the irrigation tail water combines with stormwater run-off (Zintel Canyon, Garfield Canyon, Elliot Lake, etc.). There are also numerous locations where storm run-off discharges directly or sheet flows into irrigation canals during large storm events. Some these cross-connections were identified in Figure 4-4. The necessary infrastructure to completely separate storm run-off flows from irrigation canals would be a tremendous undertaking by the City. For this reason, the future model did not separate flows between irrigation canals and City owned conveyance. Model Formation and Update The updated system inventory database files developed in GIS mapping representing the collection system (links and nodes) and drainage area (basins) were ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-11 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc exported from GIS to database files formatted for usage within HYDRA. HYDRA’s GIS Transfer Wizard was used to transfer the database files from GIS mapping format into a format files for the links and nodes, and “DR_” files for drainage basins) that could be utilized directly by HYDRA. Maintaining the unique node and link identification in GIS and HYDRA enables changes to attributes to be made in either environment. For example, whenever attributes are revised in GIS, a new database transfer can be made to update the modeled links, nodes, and basins. Similarly, whenever attributes are revised in the model database, the GIS Transfer Wizard export routine should be run to transfer information back into GIS mapping database file. Caution must be used in managing this transfer of data so that information does not un-intentionally get replaced or lost. Transferring data from GIS into HYDRA is easier as it provides updates of database files used in HYDRA. However, transferring the data the other way can completely replace information in database files used in GIS. Another concern is with the addition of links to the model. Due to the design mechanism HYDRA uses for assigning unique identification numbers to entities, it tends to renumber entities when new one are added, thus shifting the basin connection criteria for stormwater injection points. This can cause additional re- work in the model. Pizer is working to modify this in subsequent versions of HYDRA. If an additional link needs to be added, it is recommended to access the database file using a word editor to add nodes or links, then hand input the coordinates and enter the remaining attributes in the data fields in HYDRA rather than uploading from ArcGIS. Capacity Problems / Model Analysis The results of the HYDRA 6.3 model analysis can be used in conjunction with GIS mapping to visualize the problem areas of the stormwater collection system. Detailed modeling results are presented in Section 7. The 25-year storm event was used as the basis of analysis to identify these potential over capacity areas within the storm drainage system. For the existing system flows and predicted future flows, values of energy grade line (EGL) were utilized in determining the locations where the water surface elevation may be overtopping the ground surface elevations. The results of EGL were recorded in HYDRA and transferred into the GIS database files so they could be mapped across the City. Since HYDRA is a one-dimensional unsteady flow hydraulic model, it does not predict the extent of flooding over a two- or three-dimensional surface. However, the EGL can be representative of problem areas, whether they are a minor surcharge or ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-12 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc a larger area of inundation. Locations where the EGL is greater than ground surface elevations represent where there is potential flooding in roadways or the inundation of adjacent properties. In other words, it indicates that the capacity of the stormwater conveyance system under a properly maintained system is insufficient to convey peak flows through these areas. Comparison to Existing Concern Areas Nodes and links with EGL above the ground elevation were identified and compared to the areas of known flooding discussed in Section 4 as “major maintenance areas.” The results did not agree completely with the areas of concern identified in Figure 4- 4. However, they did confirm two areas of concern that were previously recommended capital improvement projects under the JUB Comprehensive Flood Control and Storm Water Drainage Plan, 1990 that still need to be completed (indicated in Figure 4-5). The first is the pipeline in Garfield St. and the second is the need for a regional retention basin located in the vicinity of 27th Ave. and Gum St. Areas of concern shown in Figure 4-4 appear to be local ponding conditions that result from poorly graded or settled pavement, inlet capacity, or maintenance needs of mainline pipe and drainage ways. This is important to the City because the model results indicate that problems in these areas can be solved with relatively simple solutions and are not indications of larger systemic problems with stormwater mainline capacity or surcharging. Future Conditions The simulation results for the 20-year build-out for the City of Kennewick had similar results as those for existing conditions. In general, the future conditions model shows pipes reaching greater capacity and several areas of increased ponding. Improvement projects are identified based on these future flow conditions. The future conditions model did not separate flows between irrigation canals and City owned conveyance. However, this report does recommend that the City, as a policy, not allow any new discharges into irrigation drainage ways and continue to take advantage of separating flows on an opportunity basis with the development and redevelopment of areas within the City. Gutter Flow A maximum allowable flow depth in gutters was considered also. A flow depth up to 4 inches was considered not to be a conveyance capacity concern. If flow depth was greater than this, then it was reflected as a potential problem area. The model is ---PAGE BREAK--- Appendix G — Hydrologic and Hydraulic Modeling Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n G-13 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix G - H&H Modeling.doc not currently predicting a problem under the existing flow conditions, but three gutter flow concerns under future flow conditions. Model Identified Improvement Projects for System Deficiencies Proposed projects to correct system deficiencies are discussed in detail in Section 7. Proposed projects are based on reducing system surcharge under the future conditions, 25-year storm event. CIP projects have been incorporated into the HYDRA model to verify that the proposed pipes will flow at 85% of capacity or lower under future flow conditions. ---PAGE BREAK--- ---PAGE BREAK--- Appendix H — Water Quality BMPs ---PAGE BREAK--- ---PAGE BREAK--- Appendix H — Water Quality BMPs C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-1 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc Introduction to Water Quality Human activity and storm runoff from the land contribute nutrients, organic matter, and silt that affect water quality. The EPA identifies sources of pollutant discharge under a “point” or “nonpoint” classification. Point sources are cultural in origin, usually pipes from sewage treatment plants, stormwater discharges, or industry. They are defined in federal regulations as “any discernable, confined and discrete conveyance, including but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, containers… from which pollutants are or may be discharged.” Agricultural stormwater discharges and return flows from irrigated agriculture are excluded from the definition of point source. Non-point sources are far more difficult to assess quantitatively and to control, and are generally related to non site-specific discharge. Numerous studies have been conducted regarding the type and quantity of non-point source pollutants found in stormwater. In general, non-point source pollutants include: • Runoff from roads and highways contains pollutants from vehicles. Typical pollutants in road runoff include: oil and grease, polynuclear aromatic hydrocarbons (PAHs), lead, zinc, copper, cadmium, sediments (soil particles), road salts, and other anti-icers. • Runoff from industrial areas contains heavy metals, sediments, and a broad range of man-made organic pollutants, including phthalates, PAHs, and other petroleum hydrocarbons. • Runoff from commercial areas contains road-based pollutant runoff, and may also contain other pollutants typical of industrial and/or residential areas. • Residential areas contribute road-based pollutants to runoff, as well as herbicides, pesticides, nutrients (from fertilizers and animal wastes), bacteria, viruses, and other pathogens (from animal wastes). After a rain event, these pollutants can be carried into surface waters affecting the habitat, hydrologic patterns and elevating pollutant concentrations and loadings. The highest concentrations of contaminants often are associated with the “first flush” discharge. This occurs from an initial storm runoff experienced after a prolonged dry period. Thus, the pollutant accumulation in intense small runoff events can be more detrimental to water quality than larger flooding events. Because of this, upstream management practices, which control small volumes of initial runoff, can be very effective in enhancing nonpoint source pollutant removal. The Washington State Department of Ecology (DOE) and the Stormwater Mangement Manual for Eastern Washington (SWMM for Eastern Washington) attempt to address these sources of pollution through a presumptive approach using Best Management Practices for Stormwater Management (BMPs). That is, providing ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-2 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc accepted technically sound stormwater management practices that, when used, are presumed to protect water quality and instream habitat – and meet the stated environmental objectives of the regulations. Project proponents do not have to follow the guidance outlined in the SWMM for Eastern Washington when handling storm runoff. However, each individual project must demonstrate that their development will not adversely impact water quality by collecting and providing appropriate supporting data to show that their alternative approach satisfies state and federal water quality laws. Because of this, the majority of project proponents will choose to develop under the presumptive approach outlined in the SWMM for Eastern Washington rather than spend the additional time and money in research and study of their project’s impact on water quality. Best Management Practices BMPs, as a concept from federal law, governs the control of nonpoint pollution sources in an effort to direct attention to management of inputs rather than collection, concentration, and treatment of the effects of inputs. The techniques are designed to reduce soil loss or prevent surface runoff from carrying heavy sediment and nutrient loads into surface water. There are three basic types of BMPs consisting of source control, water quality treatment, and flow control. Source controls consist of management or good housekeeping practices intended to reduce contact between stormwater and pollutants. Water quality treatment BMPs are intended to “remove pollutants from stormwater by filtration, biological uptake, adsorption, and/or gravity settling of particulate pollutants” (SMMEW). Flow control BMPs are designed to manage the additional volume and reduce the increased peak flow resulting from increased imperviousness in developed areas. Effective stormwater management is achieved from a management system approach. Taking into account both the effectiveness of individual BMPs in reducing pollutants, and the resulting overall cost (capital and operation), the approach must be cost-effective in meeting the goals and objectives of the City of Kennewick. In the following sub-sections, various forms of water quality BMPs are described from both federal and state resources (EPA Phase II Menu of BMPs and WDOE SMMEW). Not all water quality BMPs are presented here. Detention Facilities Detention facilities are structures designed to accommodate the temporary storage of surface water runoff such that storm runoff beyond the structure is stored or ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-3 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc released at a controlled rate. Forms of applied control include orifices, control gates, spillways, outlet dikes, and weirs. Examples of detention facilities include: • underground storage tanks vaults/pipes, • pond storage areas, and • enlarged channels and canals. Properly designed detention facilities can incorporate effective water quality treatment of pollutants contained in stormwater through the use of bio-filtration swales, filters, sedimentation basins, and wet-ponds. However, the primary benefit of detention facilities is flow control. Detention BMPs can reduce streambank erosion and flooding by temporarily detaining runoff before releasing it at flowrates and frequencies similar to those occurring under natural hydrologic conditions. Detention facilities include ponds, vaults, and tanks. Detention BMPs which utilize water ponding are generally considered the most effective treatment BMPs but may also be a source of complaints for odors or health concerns. These BMPs are known as “wet” ponds, or tanks. This type of facility can improve the removal efficiency of particular pollutants by: • Dissipating the inflow energy of the stormwater as it enters the basin • Preventing scour of material settled to the bottom • Allowing exchange of incoming stormwater with previously captured water, thus providing additional time between storms to settle pollutants. “Wet” detention BMPs with established vegetation within the storage areas provides additional pollutant removal. The vegetation serves as a filtration media for removing particular pollutants. Aquatic plants can assimilate dissolved pollutants. Biological uptake and/or transformation of pollutants into less toxic materials can be an effective method of pollutant removal. In cases where water ponding facilities cannot be established, the pollutant removal efficiency of detention facilities can be improved by extending the detention period of the runoff from the smaller, more frequent storms. Such facilities are called “extended detention” facilities. Pollutant removal from larger storms is not necessary because these infrequent storms only account for a small percentage of the long-term, average annual runoff volume. Detention BMPs designed for runoff treatment are classified to whether they provide pretreatment or primary treatment of pollutants. Pretreatment BMPs utilize sedimentation as the removal mechanism. Runoff is temporarily detained in order to settle out particulate pollutants. Where detention is used to provide primary treatment, a permanent pool of water (“dead storage”) is established that ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-4 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc can be more effective at removing pollutants than the temporary detention mechanism used by pretreatment BMPs. Wet detention BMPs may produce odors and may become a mosquito breeding ground. They may present a safety risk, and are often difficult to maintain. In the arid climate of eastern Washington, supplemental water would be needed to maintain this type of facility, therefore wet detention is not a desirable type of treatment that City can practically maintain. Dry detention basins have been used within the City of Kennewick, although historically have been discouraged. When utilized the side slopes of the detention basin should be no greater than 3 to 1, and the total depth of the detention basin should be no greater than 4-feet. Detention basins are generally recommended in areas with contributory areas of 10-acres or greater. Retention Facilities Retention facilities are structures designed to provide complete holding of surface water runoff such that runoff beyond the structure never occurs. Some form of consumption must accompany retention such as infiltration, evaporation, transportation, subsequent reuse (i.e. irrigation). Examples of retention facilities include: • infiltration drywells • infiltration trenches • infiltration ponds • evaporation ponds • surface depressions Retention facilities have been, and will continue to be, the preferred form of treatment for the City with a requirement for developers to retain the entire 10 year post-developed storm event for the project area. Typically, residential developments have satisfied this requirement through a combination of retention storage ponds and/or infiltration dry-wells. An area that has been historically overlooked by the City is the volume and conveyance of overflow for the private retention facilities. Future overflow events should be considered by development engineers to ensure facility failure or storms greater than 10 years return frequency. Overflow routes should be designated and evaluated to avoid environmental damage through erosion and scouring as well as damage to adjacent land owners and/or City owned facilities. The City of Kennewick should only accept retention facilities in the form of infiltration. Relying on evaporation and/or transportation would result in similar issues to those identified for wet detention. The side slopes of the retention basin ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-5 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc should be no greater than 3 to 1 and the total depth of the retention basin should be no greater than 4-feet. Retention basins may be used in areas with contributory areas of 1-acre or greater, up to a maximum 10-acres, depending on sub surface infiltration capacity. Infiltration and filtration of stormwater is described in the following section. Infiltration and Filtration Best Management Practices Infiltration and filtration are two stormwater management techniques that are used frequently within industry for storm water quality management. The City of Kennewick relies heavily on infiltration to provide water quality treatment, as well as, run-off disposal. Filtration systems are not used frequently within the City’s stormwater system, but may become more desirable in time to meet the development and redevelopment requirements stipulated in the SMMEW for Core Requirement Run-off Treatment. In areas where direct discharge to surface waters or infiltration is not available, land may not be available to adequately treat storm run- off in an above ground facility. Filtration systems use treatment media such as engineered natural soils or imported media to treat pollutants. A filtration BMP may have an underdrain system that conveys treated runoff away from the filtration system to an appropriate discharge location. Infiltration systems allow runoff to percolate into the soil where pollutants are removed and ground water recharged. The benefits of infiltration include preservation of baseflow in streams, recharge of ground water, reduction of peak runoff flows which can cause erosion, flooding, and a reduction or elimination of expensive stormwater conveyance systems. Dry-wells, retention ponds, grassy swales, and infiltration media are examples of an infiltration BMPs. Infiltration BMPs are not practical in all cases. The feasibility of using infiltration depends on the nature of the soils, the location and depth to bedrock, the ground and water table, and impermeable soil strata. Any one of these can reduce or eliminate the feasibility of using infiltration BMPs. In addition, the proximity of infiltration BMPs to wells, foundations, septic tank drainfields, unstable slopes, and other features can restrict their use. As a supplement to the SMMEW, DOE has published a document specifically addressing UICs within the State’s water quality program titled “Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface infiltration Facilities in Washington State.” Under the presumptive approach, this document provides a series of tables to assist the City in determining the adequacy of water quality treatment for UIC facilities. The following Tables 7-1 through 7-2 have been taken directly out of the DOE supplemental document and ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-6 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc Table 7-1 Treatment capacity of vadose zone materials (subsurface geologic matrix below the facility and above an unconfined aquifer) for removing solids, metals, and oil from stormwater discharged to UIC facilities. (For use with Tables 7-2 and 7-3) Presumed treatment capacity and conditions Description of vadose zone layer HIGH In order for the facility to be considered for exemption from the pre-treatment requirement, a minimum thickness of six feet of these materials must be naturally present between the bottom of the UIC structure and the top of the highest known seasonal water table. * Materials with average grain size <0.125mm or having a sand to silt/clay ratio of less than 1:1 and sand plus gravel less than 50% Materials with hydraulic conductivity less than 10-3 cm/s Lean, fat, or elastic clay Sandy or silty clay Silt, loess Clayey or sandy silt Sandy loam or loamy sand Silt/clay with inter-bedded sand Well-compacted, poorly-sorted materials This category includes till, hardpan, and caliches MEDIUM In order for the facility to be considered for exemption from the pre-treatment requirement, a minimum thickness of ten feet of these materials must be naturally present between the bottom of the UIC structure and the top of the highest known seasonal water table.* Materials with average grain size 0.125mm to 4mm or having a sand to silt/clay ratio between 1:1 and 9:1 and percent sand greater than percent gravel Materials with hydraulic conductivity from 10-3 to 10-1 cm/s Fine, medium or coarse sand; silty sand Sand with inter-bedded clay and/or silt Poorly-compacted, poorly-sorted materials This category includes some alluvium and outwash deposits LOW In order for the facility to be considered for exemption from the pre-treatment requirement, a minimum thickness of twenty five feet of these materials must be naturally present between the bottom of the UIC structure and the top of the highest known seasonal water table. Materials with average grain size >4mm to 64mm or having a sand to silt/clay ratio greater than 9:1 and percent sand less than percent gravel Materials with hydraulic conductivity from 10-1 to 1 cm/s Poorly-sorted, silty or muddy gravel Sandy gravel, gravelly sand, or sand and gravel This category includes some alluvium and outwash deposits NONE Materials with average grain size >64mm or having total fines (sand and mud) less than 5% Materials with hydraulic conductivity greater than 1 cm/s Well-sorted or clean gravel Boulders and/or cobbles Fractured rock This category includes fractured basalt, other fractured bedrock, and cavernous limestone * See the narrative in Section 4.4.5 of Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State for possible exceptions to the thickness requirement. Note that this table does not address the matrix within which the facility is constructed, nor does it address the entire depth of the vadose zone below the bottom of the facility. ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-7 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc Table 7-2 Pollutant loading classifications for solids, metals, and oil in stormwater runoff directed to UIC facilities. (For use with Tables 7-1 and 7-3) Pollutant loading classification Proposed land use or characteristics of the area contributing runoff to the UIC facility * INSIGNIFICANT Impervious surfaces not subject to motorized vehicle traffic or application of sand or deicing compounds Un-maintained open space LOW Inside Urban Growth Management Areas, fully controlled and partially controlled limited access highways with ADT** less than 15,000 and other roads with ADT less than 7,500 vehicles per day Outside Urban Growth Management Areas, all roads with ADT** less than 15,000 vehicles per day Parking areas with <40 trip ends** per 1,000 SF of gross building area or <100 total trip ends Other land uses with similar traffic/use characteristics (e.g. most residential parking and employee-only parking areas for small office parks or other commercial buildings) MEDIUM Inside Urban Growth Management Areas, fully controlled and partially controlled limited access highways with ADT** between 15,000 and 30,000 vehicles per day and other roads with ADT between 7,500 and 30,000 vehicles per day Outside Urban Growth Management Areas, all roads with ADT** between 15,000 and 30,000 vehicles per day Parking areas with between 40 and 100 trip ends** per 1,000 SF of gross building area or between 100 and 300 total trip ends Primary access points for high-density residential apartments Intersections controlled by traffic signals that do not meet the definition of a high-density intersection (see Glossary) Transit center bus stops Other land uses with similar traffic/use characteristics (e.g. visitor parking for small to medium commercial buildings with a limited number of daily customers) HIGH All roads with ADT** >30,000 vehicles per day High-density intersections (see definition in the Glossary) Parking areas with >100 trip ends** per 1,000 SF of gross building area or >300 total trip ends On-street parking areas of municipal streets in commercial and industrial areas Highway rest areas Other land uses with similar traffic/use characteristics (e.g. commercial buildings with a frequent turnover of visitors, such as grocery stores, shopping malls, restaurants, drive- through services, etc.) * See also Chapter 3 - Prohibitions and Sections 4.1 – Treatment Requirements to Preserve Infiltration Rates, and 4.4.1 – Special Treatment Requirements for Solids, Metals, and Oil of Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State; all prohibitions and special treatment requirements still apply. **Average daily traffic counts and trip ends must be calculated for twenty years following completion of the project and may be determined using “Trip Generation” published by the Institute of Transportation Engineers. ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-8 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc Table 7-3 Matrix for determining suitability of subsurface discharge of stormwater from commercial and residential land uses to new UIC facilities without structural pre-treatment to remove solids, metals and oil. (For use with Tables 7-1 and 7-2) All project proponents should read the entirety of the Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State for exceptions or other requirements that apply in certain situations. Appropriate pre-treatment technologies must be selected using the information provided in Ecology’s stormwater management manuals. Treatment capacity Pollutant loading High Medium Low None Insignificant Suitable for all UIC facilities Suitable for all UIC facilities Suitable for all UIC facilities Suitable for all UIC facilities Low Suitable for all UIC facilities Suitable for all UIC facilities Suitable for all UIC facilities Pretreatment required to remove solids 4 Medium Suitable for two- stage drywells 2 Suitable for two- stage drywells 2 Pretreatment required to remove solids 4 Pretreatment required to remove solids 4 High 1 Pretreatment required to remove oil 3 Pretreatment required to remove oil 3 Pretreatment required to remove oil and solids 3,4 Pretreatment required to remove oil and solids 3,4 1 Note that the prohibitions listed in Chapter 3 of Determination of Treatment and Source Control Requirements for Stormwater Discharges to Subsurface Infiltration Facilities in Washington State and any special treatment requirements. 2 A two-stage drywell includes a catch basin or other pre-settling/spill control structure that traps small quantities of oils and solids. The catch basin or other pre-settling/spill control device must be inspected and cleaned regularly (see the operation and maintenance requirements in Ecology’s stormwater management manuals). Any special treatment requirements in this chapter still apply. 3 Treatment to remove oil means oil control as defined in the SMMEW. 4 Treatment to remove solids means basic treatment as defined in the Glossary. Removal of solids should remove a large portion of the metals in most stormwater runoff. Any special treatment requirements in this chapter still apply. For low pollutant loading sites, implementation of appropriate source control BMPs may be employed in lieu of structural treatment BMPs (see Ecology’s stormwater management manuals). ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-9 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc are provided for this Stormwater Plan discussion. The tables should be used in accordance with the requirements and intent outlined in the supplement document and the SMMEW. Experience has shown that infiltration can be successfully utilized with conformance to proper design, construction, and maintenance standards. When operating problems with infiltration BMPs have occurred, the primary causes of failure have been: • Inadequate soil investigation, resulting in a poorly designed system; • Improper construction practices, especially compaction of soil; • Irregular maintenance in the removal of wind blown and water laden siltation which clogs soils used for infiltration. This problem is most typically the result of improper control of construction-related erosion and sedimentation. All infiltration and filtration BMPs should be preceded by a pretreatment BMP to remove suspended solids. Infiltration in land use areas where activities may generate a highly contaminated runoff must be preceded by pretreatment. When designing infiltration and/or filtration systems, designers and maintenance programs need to ensure that appropriate provisions for long-term maintenance are followed. The infiltration rate should be greater than 0.5 inches per hour. Based upon proper soil conditions, groundwater must be located a minimum of 2-feet below the bottom of infiltration or filtration system with 5-feet below as the preferred separation. Porous pavement has been suggested by some state and federal regulatory authorities to allow for infiltration of storm water through the pavement surface to the underlying subsoil. Porous pavement is not recommended for the City of Kennewick. Blowing dust and sand, winter sanding, and freezing of moisture in the subsoil resulting in pavement heaving all prevent the use of this practice in eastern Washington. Biofiltration Swales and Vegetative Filter Strips Biofiltration swales and vegetative filter strips are two practices which are used in stormwater management. Because these two BMPs are non-structural, they are considered desirable alternatives to ponds, tanks, and vaults. There are two types of biofiltration-type BMPs: the biofiltration swale and the vegetated filter strip. A biofiltration swale is a vegetated channel that is sloped like a standard storm drain channel. Stormwater enters at one end and exits at the other with treatment provided as the runoff passes through the channel. With vegetated ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-10 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc filter strips the flow is distributed broadly along the width of the vegetated area. Treatment is provided as runoff travels as sheet flow through the vegetation. The method chosen will depend upon the drainage patterns of the site. A vegetated strip would function well where the water can be spread along the length of a parking lot. Gaps in the lot curb provide the entry points. The grade of the parking lot must be flat immediately parallel to the strip. Biofiltration swales and vegetative filter strips use similar pollutant removal mechanism, i.e., “biofiltration.” The term “biofiltration” has been coined to describe the more-or-less simultaneous processes of filtration, infiltration, adsorption, and biological uptake of pollutants in stormwater that take place when runoff flows over and through vegetated treatment facilities. Vegetation growing in these facilities acts as both physical filter which causes gravity settling of particulates by regulating velocity of flow, and also as a biological sink when directed uptake of dissolved pollutants occurs. Another means of removing pollutants occurs as the stormwater contacts the soil surface and infiltrates into the underlying soil. Dissolved pollutants are adsorbed onto soil particles. This is a potentially important removal mechanism for both dissolved heavy metals and phosphorus by undergoing ion exchange with elements in the soil. In addition, biological activity in the soil can metabolize organic contaminants. The degree to which the above mechanisms operate will vary considerably depending upon many factors such as the depth and condition of the vegetation, the velocity of the water, the slope of the ground, and the texture of the underlying soil. Bioretention systems are landscapes depressions generally located adjacent to roadways or parking lots. They are similar to biofiltration swales and vegetative filter strips. Surface drainage is directed into the depressions were storm water either infiltrates to subsoil, or during larger storms, flows through the biorentention area to storm drain system. Bioretention systems are applied to drainage areas of 1-acre, and no greater than 5-acres. Catch Basins The catch basin has been utilized throughout the United States as a storm water BMP for many years. Over the last century, the catch basin has evolved from a simple hole that allowed storm water to enter a storm drain, to a storm drain inlet or curb inlet that includes a grate to filter out leaves and floating debris, a sump ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-11 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc that captures sediment, and a hooded outlet that prevents debris from entering the storm drainage system. Catch basins are ideally suited as a pretreatment device for other BMPs that may be required They do not remove soluble pollutants or fine particles that may be in suspension, and generally require frequent maintenance to avoid resuspension of sediments. General criteria for sizing of catch basins are related to the diameter of the outlet pipe The diameter of the catch basin should be a minimum of 24-inches in diameter. The sump depth should be at least 24-inches below the lowest pipe invert Recently, manufacturers have developed “catch basin inserts” which can be installed in catch basins to filter runoff entering the catch basin. These devices are not recommended for the City of Kennewick because they have a very small inlet capacity compared to that of the catch basin and they require very frequent and costly sediment removal and/or replacement. One design option that has recently been implemented for use in residential areas is to incorporate infiltration through a small drainhole in the catch basin bottom. This helps to eliminate stagnate water and mosquito breeding ponding areas in the catch basin sump. Infiltrating catch basins of this type should not be used in commercial or industrial areas, along major arterials, or in fill areas. Oil/Water Separators Oil/water separators have limited application in stormwater treatment because their treatment mechanisms are not well-suited to the characteristics of stormwater runoff highly variable flow with high discharge rates, turbulent flow regime, low oil concentration, high suspended solids concentration). In addition, separators can require intensive maintenance, further restricting their desirability as a stormwater treatment BMP. The primary use of oil/water separators will be in cases where oil spills are a concern, in which case a spill control separator may be required. There will be but a few other cases where an oil/water separator would be required, as other BMPs are more appropriate for controlling oil. Source control in particular should be the first option and may negate the need for special treatment. Other than to capture spills, the use of oil/water separators should be restricted to development sites that have high oil and grease loadings, such as petroleum storage yards and vehicle storage and/or maintenance facilities. There are three general types of separators. The first type is the Spill Control separator (SC). It is a simple underground vault catch basin, or manhole with a inlet. The SC-separator is effective at retaining small spills. The SC-separator will ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-12 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc not remove diluted oil droplets spread through the stormwater from oil- contaminated pavement. The SC – separator may be used at major intersections, along arterials, when required to restore a beneficial use of surface water. The SC separator is an integral part of the Stage 2 Drywell facility when used as the collection system for the drywell. The SC separator is shown in Figure 1. Figure 1 – Spill Control Separator (not for oil treatment) The other two types of separators can remove dispersed oil and should be installed at petroleum storage yards and vehicle fueling/storage and/or maintenance facilities: The American Petroleum Institute (API) separator and Coalescing Plate Separator (CP) is a long vault or basin with baffles to improve the hydraulic conditions for treatment. Large API-separators can be equipped with sophisticated mechanical equipment for removing oil from the surface and settled solids from the bottom. The CP-separator contains a bundle of plates made of fiberglass or polypropylene. The plates are closely spaced. Depending on the manufacturer and/or application, Source: Ecology’s Stormwater Management Manual, 1992 ---PAGE BREAK--- Appendix H — Water Quality BMPs Continued C i t y o f K e n n e w i c k C o m p r e h e n s i v e S t o r m w a t e r P l a n H-13 otak K:\project\30300\30386\Reports\Final Report\Appendices\Appendix H - Water Quality BMPs.doc the plates may be positioned in the bundle at an angle of 45 to 60 from the horizontal. The closely spaced plates improve the hydraulic conditions in the CP- separator promoting oil removal. The primary advantage of the CP-separator is its ability to theoretically achieve equal removal efficiencies with one-fifth to one-half the space needed by the API separator, when designed to remove the same size droplets. Summary The BMPs presented in this discussion are technically accepted stormwater management practices used to protect water quality and instream habitat. The information is from Ecology’s SWMM for Eastern Washington. When applied correctly, the BMPs are presumed to provide an adequate level of treatment. It should be noted that project proponents are not required to follow the guidance in the SWMM for Eastern Washington. However, projects that do not apply the accepted BMPs must provide supplemental data to show that their alternative approach satisfies the state and federal water quality laws. Because of the additional time and money required to determine a project’s actual impact on water quality, most project proponents will choose to develop using Ecology’s accepted BMPs.