Full Text
N O T G S T A T A T W F O E N I H S E R E D R E G I S ---PAGE BREAK--- DEVORE RESIDENCE 11235 − 165TH CT NE REDMOND, WASHINGTON PN: [PHONE REDACTED] CIVIL & T.E.S.C. PLAN N O T G S T A T A T W F O E N I H S E R E D R E G I S Know what's R ---PAGE BREAK--- DEVORE RESIDENCE 11235 − 165TH CT NE REDMOND, WASHINGTON PN: [PHONE REDACTED] CIVIL GENERAL NOTES & DETAILS N O T G S T A T A T W F O E N I H S E R E D R E G I S Know what's R R=25' MIN. 8" QUARRY SPALLS IF A ROADSIDE DITCH IS PRESENT, INSTALL DRIVEWAY CULVERT PER NOTES: • PER KING COUNTY ROAD DESIGN AND CONSTRUCTION STANDARDS DRIVEWAYS SHALL BE PAVED TO EDGE OF R-O-W PRIOR TO INSTALLATION OF THE CONSTRUCTION ENTRANCE TO AVOID DAMAGING OF THE ROADWAY. • IT IS RECOMMENDED THAT THE ENTRANCE BE CROWNED SO THAT RUNOFF DRAINS OFF THE PAD. GEOTEXTILE 12" MIN. THICKNESS PROVIDE FULL WIDTH OF INGRESS/EGRESS AREA 100' MIN. EXISTING ROAD 15' MIN. JOINTS IN FILTER FABRIC SHALL BE SPLICED AT POSTS. USE STAPLES, WIRE RINGS OR EQUIVALENT TO ATTACH FABRIC TO POSTS. 2"X2" BY 14 Ga. WIRE OR EQUIVALENT, IF STANDARD STRENGTH FABRIC USED FILTER FABRIC WIRE BACKING IS USED 6' MAX. POST SPACING MAY BE INCREASED TO 8' IF NOTE: FILTER FABRIC FENCES SHALL BE INSTALLED ALONG CONTOURS WHENEVER POSSIBLE MINIMUM 4"x4" TRENCH BACKFILL TRENCH WITH NATIVE SOIL OR 3/4" TO 1-1/2" WASHED GRAVEL 2"x4" WOOD POSTS, STEEL FENCE POSTS, REBAR, OR EQUIVALENT 2' MIN. 12" MIN. ---PAGE BREAK--- DEVORE RESIDENCE 11235 − 165TH CT NE REDMOND, WASHINGTON PN: [PHONE REDACTED] CIVIL GENERAL NOTES & DETAILS N O T G S T A T A T W F O E N I H S E R E D R E G I S Know what's R LEVEL OUTLET 18" MIN. 6" MIN. RIGID PERFORATED PIPE, 4" MIN. DIA. 3/4" TO 1-1/2" WASHED DRAIN ROCK 24" MIN. TRENCH SECTION NTS EDGE OF UNDISTURBED NATIVE VEGETATION SMALL CATCH BASIN OR YARD DRAIN = 1,400 SQ FT FOR A 100-FT NVFS = 2,800 SQ FT FOR A 200-FT NVFS TYPE 1 CB = 5,000 SQ FT FOR A 100-FT NVFS = 10,000 SQ FT FOR A 200-FT NVFS 50' SEPARATION BETWEEN FLOWPATH SEGMENTS, TRENCHES 10-FOOT-LONG DISPERSION TRENCH NATIVE VEGETATED FLOWPATH SEGMENT (NVFS) 100 FEET MINIMUM =15% SLOPE MIN. 100-FT-LONG NVFS PLAN VIEW OF ROOF NTS MIN. 6" DIA. RIGID PIPE 50-FOOT-LONG DISPERSION TRENCH WITH NOTCH BOARD SEE FIGURE C.2.1.D MAX 20% SLOPE MAX 15% SLOPE PIPE O.D. 0 MIN. 0 MIN. END CAP OR PLUG CLEAN OUT WYE FROM PIPE MIN 6" PERFORATED PIPE LAID FLAT/LEVEL TYPE I CB W/SOLID COVER (LOCKING) A 50' INFLUENT PIPE (MAX DESIGN FLOW <0.5 CFS PER TRENCH) CLEAN OUT WYE FROM PIPE FLOW TO OTHER BRANCHING CB'S AS NECESSARY NOTCHED GRADE BOARD 2" X 2" NOTCHES 18" O.C.* PLAN NTS PIPE O.D. GALVANIZED BOLTS 0 MIN. 1'-0 MIN. 2" GRADE BOARD NOTCHES* *FOR WATER QUALITY FACILITIES, SEE SECTION 6.2.6.1, OPTION A FOR NOTCH DIMENSIONS AND SPACING 2"x12" GRADE BOARD 4" X 4" SUPPORT POST FILTER FABRIC TRENCH LINER CLEAN FINES) WASHED ROCK NOTES: MIN 6" PERFORATED PIPE LAID FLAT 1. THIS TRENCH SHALL BE CONSTRUCTED TO PREVENT POINT DISCHARGE AND/OR EROSION. 2. TRENCHES MAY BE PLACED NO CLOSER THAN 50 FEET TO ONE ANOTHER (100 FEET ALONG FLOWLINE). 6" MIN. SECTION A-A NTS 3. TRENCH AND GRADE BOARD MUST BE LEVEL. ALIGN TO FOLLOW CONTOURS OF SITE. 4. SUPPORT POST SPACING AS REQUIRED BY SOIL CONDITIONS TO ENSURE GRADE BOARD REMAINS LEVEL. 5. 15% MAX UNLESS OTHERWISE EVALUATED AND APPROVED, SEE SECTION C.2.1.1 18" O.C.* 2" A FLOW TO SECOND DISPERSAL TRENCH IF NECESSARY TYPE I CB W/SOLID COVER 20% MAX, SEE NOTE 5 15% MAX 12" MIN. 36" MAX. 1 1 2 " 3 - 4" ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 1 DRAINAGE TECHNICAL INFORMATION REPORT Proposed Single Family Residence 11235 – 165th Ct NE Redmond, Washington PN: [PHONE REDACTED] For John & Karen Devore 11235 – 165th Ct NE October 3, 2017 By Development Engineering, PLLC P.O. Box 446 Tacoma, WA 98401 Ph: (253) 228-0513 www.de-civil.com ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 2 TABLE OF CONTENTS Page Cover 1 Table of Contents 2 Section 1: Project Overview 3 Section 2: Conditions and Requirements Summary 3 Section 3: Offsite Analysis 4 Section 4: Flow Control and Water Quality 5 Section 5: Conveyance System 6 Section 6: Special Reports and Studies 7 Section 7: Other Permits 7 Section 8: 7 Section 9: Bond Quantities 7 Section 10: Operations and Maintenance 7 Table A: Proposed Imperious Surface Figure 1 – TIR Worksheets 8 9 Figure 2 – Vicinity Map 14 Figure 3 – Existing Site Conditions 15 Figure 4 – USDA Soils Map 16 Figure 5 – USDA Soils Map Table 17 Figure 6 – Analysis Table 18 Figure 7 – Analysis Map 19 Figure 8a-8c – Analysis Pictures 20 Figure 9 – Basin Study Map 23 Figure 10 – Sensitive Area 24 Figure 11 – Drainage Complaints 25 Figure 12 – 100yr 24hr Isopluvial Map 26 Figure 13 – Drainage Basin Map 27 Appendix A Maintenance 28 Appendix B Declaration of Covenant 32 Appendix C WWHM 37 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 3 Section 1 - PROJECT OVERVIEW We are pleased to submit this drainage report for the construction of the proposed garage and driveway on the existing tax parcel, to be located at 11235 – 165th Ct NE in Redmond, in King County Washington, as shown on the attached Site Vicinity Map, Figure 2. It is our understanding from the discussions that we have had, our knowledge with the area and our site visit on July 23, 2017, that you intend to construct a garage/shop on this tax parcel which will utilize conventional wood framing and concrete footings. Since the impervious surfacing you’ve planned to install totals to less than 5,000sqft, King County will require you to submit a “Simplified Drainage Review”, requiring you to comply with all nine core requirements from section 1.2 and all five special requirements from section 1.3 of the King County SWDM 2016. Pre-Developed Site Conditions The site is an existing lot of record that is currently the location of a single family residence. The site consists of a single parcel that is irregular in shape, encompassing a total area of 0.95 acres. The site has remained in this developed state since 2000 according to King County Imap historical aerial photos. The site is generally slopes down from west to east at slopes of approximately 0 to 8 percent. Total topographic relief across the parcel is approximately 15 feet. Post-Developed Conditions Based on our conversations with the owner and our review of the provided site plan, it is our understanding that the proposed development will include the construction of a garage and an access to it, stemming from the point where 133th St splits into 165th Ct NE and 166th Ct NE. The proposed garage will measure 1,287sqft; the additional driveway will measure 2,974sqft in area. A new 115sqft impervious walkway will also be installed, for a total of 4,376sqft of new impervious area since 2000. Upon completion of the developments, all pervious surfacing will be allowed to regrow to native conditions, see Section 4 – Flow Control for WWHM modeling. The proposed development will result in 10,741sqft of total impervious area on the property, or 25.8% of the total lot area. Disturbed area will be limited the area surrounding the proposed impervious area, making the clearing limits for the development 0.2 acres. See Figure 5, Developed Site Conditions and Table for a complete breakdown of the site areas. Due to the amount of impervious area added, we intend to use full dispersion in accordance with King County requirements for full dispersion for managing stormwater runoff. Site Soils The USDA NRCS web application maps the soils on the site as Alderwood gravelly sandy loam (AgB, AgC, AgD), wich derive from glacial drift and/or outwash on slopes of 0 to 30 percent. These soils are known to have a very low to moderately low capacity to transmit water. An excerpt from the USDA soil survey is included as Figure 4. Section 2 - Conditions and Requirements Summary Per the FEMA Flood Map no portion of the site is located within a 100 year flood plain. According to the SWMM the site should be subject to “Full Drainage Review”. The site will disturb more than 7,000sqft of area and will add more than 5,000sqft of new impervious area since 2000. It is assumed that basic dispersion will be necessary and will comply with stormwater management as they pertain to the rules and regulations set forth by King Counties SWMM, 2016. ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 4 Surface Water Design Manual Minimum Core Requirements: Core Requirement 1. Discharge at the natural location: The site currently drains to the southwest as sheet flow. Core Requirement 2. Off-Site Analysis: An Off-Site Analysis is included in Section 3 of this report. The analysis includes site inspection and research as required to meet the requirements of a “Level – 1” off-site analysis. Core Requirement 3. Flow Control: Flow Control is managed through the implementation of basic dispersion for all roof areas with flow paths dispersed through native forested conditions. Runoff from 2,974sqft of driveway will be sheet flowed into a vegetative flow path running adjacent to the impervious surface, whereas the other 1,287sqft of roof area will be conveyed to a dispersion trench. See WWHM calculations below for a full breakdown. Core Requirement 4. Conveyance System: A detailed conveyance analysis is included in Section 4 of this report. Core Requirement 5. Temporary Erosion & Sediment Control: Basic erosion control measures have been shown on the attached plans with a more detailed explanation given in Section 8 of this report. Core Requirement 6. Maintenance & Operation: An “O&M” Manual has been included as part of this report. Core Requirement 7. Financial Guarantees & Liability: A bond will not be required as this is a single family development. Core Requirement 8. Water Quality: The project will be required to meet the “Basic” water quality menu. The total amount of impervious pollution generating area is less than 5,000sqft at 2,974sqft therefore this requirement is not applicable. King County Surface Water Design Manual Special Requirements: Per the FEMA Flood Map no portion of the site is located within the 100 year flood plain. Wetlands are not mapped on the site, and no development is proposed within any wetland buffer areas without proper permitting and mitigation. Section 3 – Level Offsite Analysis Task 1. Study Area Definition and Maps The site is located within the Sammamish River Watershed. Site topography slopes down from southwest to northeast. Native drainage was difficult to observe due to vegetation and topography, but runoff from this area is directed north along 165th Ct NE until reaching a retention pond approximately 1,000 feet north of the property. Onsite stormwater is being dispersed and therefore will not affect native drainage patterns. Task 2. Resource Review The following is a summary of the resources reviewed to identify any potential sensitive areas within, adjacent to and of the proposed site. ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 5 Wetlands: iMap mapping shows no wetlands located within the site area. Streams and 100-year Floodplains: No flooding hazard is mapped on or near the property. Construction will not interfere with the pond on neighboring property. Erosion Hazard Areas: iMap mapping shows no erosion hazards on or near the property. Landslide Hazard Areas: iMap mapping shows no landslide hazard on or near the property. Seismic Hazard Areas: iMap shows no seismic hazard on or near the property. Drainage Complaints: iMap mapping shows that no drainage complaints exist near the property. See Figures for maps. Task 3. Field Inspection Level 1 Inspection: 1. Investigate any problems reported or observed during the resource review. No problems were identified within the resource review. 2. Locate all existing/potential constrictions or lack of capacity in the existing drainage system. No problems identified. 3. Identify all existing/potential drainage problems as defined in Section 1.2.2.1. No significant drainage problems were noted on and around the site. 4. Identify existing/potential overtopping, scouring, bank sloughing, or sedimentation. No evidence was observed of these issues. 5. Identify significant destruction of aquatic habitat or organisms. None noted. 6. Collect qualitative data on features such as land use, impervious surfaces, topography, and soil types. The site and surrounding areas generally consists of residential properties in close proximity to neighboring residences. 7. Collect information on pipe sizes, channel characteristics, drainage structures, and relevant critical areas wetlands, streams, steep slopes). No pipes or culverts noted on site. There are no steep slopes located on the site; careful attention has been paid to the proposed development to minimize any impacts to the existing natural drainage patterns. 8. Verify tributary basins delineated in Task 1. The attached Figure 7 Basin Study Area accurately reflects the basin areas based on our field observations. 9. Contact neighboring property owners or residents in the area about past or existing drainage problems, and describe these in the report (optional). Not done. 10. Note the date and weather conditions at the time of the inspection. The inspection was performed in the afternoon of July 23, 2017. The weather was warm and clear It had not rained heavily for several weeks at the time of the visit. Section 4 - Flow Control and Water Quality Analysis and Design The proposed drainage will be maintained on site using basic dispersion techniques as they pertain to the rules and regulations set forth by King County Stormwater Management Manual (SWMM, 2016). As such we are proposing to apply basic dispersion to 2,974ft of driveway impervious surfacing. A 10-foot vegetative flow path will be installed running adjacent to the impervious surface. For roof impervious areas, we are tightlining stormwater runoff to a dispersion trench located west of the proposed garage. The roof area of 1,287sqft requires a trench with a width of 18.4 feet in order to fully disperse stormwater runoff. The flow path associated with the dispersion trench must be 25 feet in length. ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 6 Since we are using a 20-foot wide trench with a 25-foot flow path, we have met requirements for minimum sizing of dispersion trenches for roof drainage. We have provided WWHM calculations comparing the peak flow from the site in the pre-developed form and in the proposed developed form. The developed impervious areas being fully dispersed are not included in the calculations. The breakdown of the areas, mitigation and results of the changes to the 100yr peak flows are summarized below in Table 1 through 4, output is included for reference. It can be seen that less than a 0.1 cfs difference between predeveloped and mitigated peak flows has been achieved, therefore fulfilling the requirements for flow control. Table 1 Pre-Developed Basin Areas Area (acres) Modelled as 0.2 acres Type C Forest Table 2 Developed Areas & Mitigation Area (acres) BMP Used to Mitigate Modelled As Roof Area 0.0295 Basic Dispersion Modeled as 90% impervious, 10% grass Driveway 0.0683 Basic Dispersion Modeled as 90% impervious, 10% grass Table 3 Developed Basin Area (acres) Impervious surfacing 0.08802 Type C Lawn 0.11198 Total 0.2 Table 4 Flow Comparison 100yr Flow Pre-Developed Forested 0.0158 cfs Developed 0.1045 cfs Difference 0.0887 cfs Section 5 - Conveyance System Analysis and Design Roof stormwater runoff will be tightlined to a dispersion trench located west of the proposed garage. The roof area of (1,287sqft) or (0.029acres) will be drained to the trench. Based on manning’s flow equation and an n value of 0.013, the pipe capacity will be 0.32 cfs for a 4” line and 0.66 cfs for a 6” line. Using the rational method as found in the the 100 year peak flow is 0.9x0.029x3.9x0.95=0.097cfs. The 4- inch line has the capacity to convey the stormwater runoff to the dispersion trench. ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 7 Section 6 – Special Reports and Studies. None noted Section 7 – Other Permits A Building Permit will be required. Section 8 – Analysis and Design Typical erosion control measures have been shown on the provided plans. Given the limited amount of area to be worked at any given time and the near surface soils, the chance of erosion from leaving the site is minimal. While we have shown a silt fence along the down slope portions of the clearing limits, it is our opinion that little surface runoff will leave the site uncontrolled and that this will be adequate erosion protection for the site. Surface areas that are cleared are expected to be seeded or landscaped shortly after they have been cleared further minimizing the chance for erosion. In our opinion the plans as prepared are adequate for a project of this nature. Section 9 – Bond Quantities, Facility Summaries, and Declaration of Covenant A Declaration of Covenant is included in this report under “Appendix Section 10 - Operations and Maintenance Manual An operation and maintenance manual is included with this report. ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 8 Table A Proposed Impervious Surfaces: Fill in all applicable blanks below to list the square footage of all new and existing impervious surface areas proposed on your parcel. When calculating impervious surface areas for buildings do not list living/useable space, instead list the building roof square footage, measured to the outside edge of eve or gutter. New Existing Total Roof Area: sq. ft. 4,055 _ sq. ft. sq. ft. (House, Attached Garage, Covered Patio, Deck, & Porch) Roof Area: ___1,287__ sq. ft. _ sq. ft. _1,287____ sq. ft. (Detached Garage) Roof Area: sq. ft. 144 _ sq. ft. ___144 _ sq. ft. (All Out Buildings) On-site Driveway Area __2,974_ sq. ft. _ 1,800__ sq. ft. 4,774 sq. ft. Off-site Driveway Area: sq. ft. _ sq. ft. _ sq. ft. Walkways/Sidewalks: ___115 sq. ft. sq. ft. 841__ sq. ft. Uncovered Patio Area: sq. ft. _ sq. ft. _ sq. ft. Uncovered Porch Area: sq. ft. _ sq. ft. sq. ft. Uncovered Deck Area: sq. ft. sq. ft. sq. ft. All Other Impervious Area: _ sq. ft. sq. ft. _ sq. ft. Total New Impervious Surface __4,376 sq. ft. Total Existing Impervious Surface __6,365 sq. ft. Total Impervious Area __10,741__ sq. ft. Total Clearing Limits or Graded areas __8,712 sq. ft. (Include Septic Drainfields, Primary & Reserve Total New Pervious Area: _4,336__sq. ft. [(Total Clearing Limits/Graded Areas)-(Total New Impervious Areas)] Volume of Excavation: ___400 Cubic Yards Volume of Fill (Exported): Cubic Yards Volume of Fill (Imported): Cubic Yards For DPER Staff Use ONLY Parcel Number Application Approved By: Date: ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 9 Figure 1 TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Part 2 PROJECT LOCATION AND DESCRIPTION Project Owner: John & Karen Devore Phone: Address: 11235 – 165th Ct NE Project Engineer: Glen Coad, PE Company Development Engineering, PLLC Phone (253) 228-0513 Project Name 17-172 Devore Rd.DP DDES Permit # Location Township 26 Range 05 Section 36 Site Address 11235 – 165th Ct NE Part 3 TYPE OF PERMIT APPLICATION Part 4 OTHER REVIEWS AND PERMITS Landuse Services Subdivison / Short Subd. / UPD Building Services M/F / Commerical / SFR Clearing and Grading Right-of-Way Use Other DFW HPA COE 404 DOE Dam Safety FEMA Floodplain COE Wetlands Other Shoreline Management Structural Rockery/Vault/_____ ESA Section 7 Part 5 PLAN AND REPORT INFORMATION Technical Information Report Site Improvement Plan (Engr. Plans) Type of Drainage Review (circle): Date (include revision dates): Date of Final: Full / Targeted / Large Site 1/16/2017 Type (circle one): Date (include revision dates): Date of Final: Full / Modified / Small Site 7/24/17 Part 6 ADJUSTMENT APPROVALS Type (circle one): Standard / Complex / Preapplication / Experimental / Blanket Description: (include conditions in TIR Section 2) NONE . . Date of Approval: Part 7 MONITORING REQUIREMENTS Monitoring Required: Yes / No Start Date: Completion Date: Describe: ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 10 Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan : Special District Overlays: None Drainage Basin: Sammamish River Stormwater Requirements: Conservation Flow Control & Basic Water Quality Part 9 ONSITE AND ADJACENT SENSITIVE AREAS River/Stream Lake Wetlands Closed Depression Floodplain Other Steep Slope Erosion Hazard Landslide Hazard Coal Mine Hazard Seismic Hazard Habitat Protection Part 10 SOILS Soil Type Alderwood gravelly sandy loam Slopes 0 – 30 % Erosion Potential Moderate High Groundwater Table (within 5 feet) Other Sole Source Aquifer Seeps/Springs Additional Sheets Attached Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE Core 2 – Offsite Sensitive/Critical LIMITATION / SITE CONSTRAINT Additional Sheets Attached ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 11 Part 12 TIR SUMMARY SHEET (provide one TIR Summary Sheet per Threshold Discharge Area) Threshold Discharge Area: Site (name or description) Core Requirements (all 8 apply) Discharge at Natural Location Number of Natural Discharge Locations: 1 Flow Control (incl. facility summary sheet) Level: 1 / 2 / 3 or Exemption Number Small Site BMPs Dispersion Conveyance System Spill containment located at: Erosion and Sediment Control ESC Site Supervisor: Contact Phone: After Hours Phone: Maintenance and Operation Responsibility: Private / Public If Private, Maintenance Log Required: Yes / No Financial Guarantees and Liability Provided: Yes / No Water Quality (include facility summary sheet) Type: Basic / Sens. Lake / Enhanced Basic / Bog or Exemption No. Landscape Management Plan: Yes / No Special Requirements (as applicable) Area Specific Drainage Requirements Type: CDA / SDO / MDP / BP / LMP / Shared Fac. / None Name: Floodplain/Floodway Delineation Type: Major / Minor / Exemption / None 100-year Base Flood Elevation (or range): Datum: Flood Protection Facilities Describe: Source Control (comm./industrial landuse) Describe landuse: Describe any structural controls: Oil Control High-use Site: Yes / No Treatment BMP: Maintenance Agreement: Yes / No with whom? Other Drainage Structures Describe: ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 12 Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION Clearing Limits Cover Measures Perimeter Protection Traffic Area Stabilization Sediment Retention Surface Water Collection Dewatering Control Dust Control Flow Control MINIMUM ESC REQUIREMENTS AFTER CONSTRUCTION Stabilize Exposed Surfaces Remove and Restore Temporary ESC Facilities Clean and Remove All Silt and Debris, Ensure Operation of Permanent Facilities Flag Limits of SAO and open space preservation areas Other Part 14 STORMWATER FACILITY DESCRIPTIONS (Note: Include Facility Summary and Sketch) Flow Control Type/Description Water Quality Type/Description Detention Biofiltration Infiltration Wetpool Regional Facility Media Filtration Shared Facility Oil Control Flow Control BMPs Basic Dispersion Spill Control Other Flow Control BMPs Other Part 15 EASEMENTS/TRACTS Part 16 STRUCTURAL ANALYSIS Drainage Easement Covenant Native Growth Protection Covenant Tract Other Cast in Place Vault Retaining Wall Rockery > 4’ High Structural on Steep Slope Other ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 13 Part 17 SIGNATURE OF PROFESSIONAL ENGINEER I, or a civil engineer under my supervision, have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attached Technical Information Report. To the best of my knowledge the information provided here is accurate. October 3, 2017 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 14 Not to Scale Approximate Location DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com SITE VICINITY MAP Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 2 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 15 DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com EXISTING SITE CONDITIONS Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 3 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 16 ` DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com USDA SOILS MAP Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 4 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 17 DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com USDA SOILS MAP TABLE Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 5 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 18 Symbol Drainage Component Type Name & Size Drainage Component Description Slope Distance from site discharge Existing Problems Potential Problems Observations of Field Inspector, resource reviewer, or resident See Map Type: sheet flow, swale, stream, channel, pipe, pond, size: diameter, surface area drainage basin, vegetation, cover, depth, type of sensitive area, volume % 1/4 ml=1,320 ft. constrictions, under capacity, ponding, overtopping, flooding, habitat or organism destruction, scouring, bank sloughing, sedimentation, incision, other erosion tributary area, likelihood of problem, overflow pathways, potential impacts A On-site: looking north Pasture 10 ± 0 none none B On-site: looking west Forest 10 ± 0 none none C On-site: looking southwest Forest 10 ± 0 none none D Off-site: looking south Swale 10 ± 400ft none none E Off-site – Looking west Shadow Lake 0 ± 1,500ft none none F Off-site – Looking southwest Catch basin/swale 5 ± 1,200ft none none DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com ANALYSIS CHART Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 6 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 19 DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com ANALYSIS MAP Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 7 B A C D E F ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 20 Site A Site B DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com Analysis Pictures Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 8a ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 21 Site C Site D DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com Analysis Pictures Devore Garage 11235 – 165th Ct NE Redmond, Washington ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 22 Site E Site F DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com Analysis Pictures Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 8c ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 23 DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com BASIN STUDY AREAS Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 9 Sammamish River Drainage Basin Bear Creek Drainage Basin ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 24 DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com SENSITIVE AREAS Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 10 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 25 DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com DRAINAGE COMPLAINTS Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 11 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 26 DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com 100 YR 24-HOUR ISOPLUVIAL Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 12 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 27 DE-CIVIL, PLLC P.O. Box 446 Tacoma, WA 98401 Ph (253) 228-0513 www.de-civil.com DRAINAGE BASIN MAP Devore Garage 11235 – 165th Ct NE Redmond, Washington Job No: 17-172 October 2017 Figure 13 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 28 Appendix A ”O&M Manual” ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 29 #33 – Maintenance Checklist for Downspout, Sheet Flow, and Concentrated Dispersion Systems: Drainage System Feature Defect or Problem Condition When Maintenance is Needed Results Expected When Maintenance is Performed Splash Block Water Directed Toward Building Water is being directed towards building structure. Water directed away from building structure. Splash Block Water Causing Erosion Water disrupts soil media. Blocks are reconfigured/repaired and media is restored. Transition Zone Erosion Adjacent soil erosion, uneve surface creating concentrated flow discharge; or less than 2 feet of width. No eroded or scoured areas. Cause of erosion or scour is addressed. Dispersion Trench Concentrated Flow Visual evidence of water discharging at concentrated points along trench (normal condition is a “sheet flow” from edge fo trench; intent is to prevent erosion damage). No debris on trench surface. Notched grade board or other distributor type is aligned to prevent erosion. Trench is rebuilt to standards, if necessary. Surface of Trench Accumulated Debris Accumulated trash, debris, or sediment on drain rock surface impedes sheet flow from facility. Trash or debris is removed/disposedin accordance with local solid waste requirements. Surface of Trench Vegetation Impeding Flow Vegetation/moss present on drain rock surface impedes sheet flow from facility. Freely draining draink rock surface. Pipe(s) to Trench Accumulated Debris in Drains Accumulation of trash, debris, or sediment in roof drains, gutters, driveway drains, etc. No trash ordebris in roof drains, gutters, driveway drains, or area drains. Pipe(s) to Trench Accumulated Debris in inlet Pipe Pipe from sump to trench or drywellhas accumulated sediment or is plugged. No sediment or debris in inlet/outlet pipe screen or inlet/outlet pipe. Pipe(s) to Trench Damaged Pipes Cracked, collapsed, broken, or misaligned pipes. No cracks more than 0.25- inch wide at the joint of the inlet/outlet pipe. Sump Accumulated Sediment Sediment in the sump. Sump contains no sediment. Access Lid Hard to Open Cannot be easily opened. Access lid is repaired or replaced. Access Lid Buried. Buried. Access lid functions as designed (refer to record drawings for design intent). Access Lid Missing Cover. Cover missing. Cover is replaced. Rock Pad Inadequate Rock Cover Only one layer of rock exists above native soil in area 6 square feet or larger, or any exposure of native soil. Rock Pad is repaired/replaced to meet design standards. Rock Pad Erosion Soil erosion in or adjacent to rock pad. Rock pad is repaired/replaced to meet design standards. Dispersal Area Erosion Erosion (gullies/rills) greater than 2 inches deep in dispersal area. No eroded or scoured areas. Cause of erosion or scour is addressed Dispersal Area Accumulated Sediment Accumulated sediment or debris to exten that block or channelizes flow path. No excess sediment or debris in dispersal area. Sediment source is addressed (if feasible). ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 30 Ponded Water Ponded Water Standing surface water in dispersion area remains for more than 3 days after the end of a storm event. System freely drains and there is not standing water in dispersion area between storms. There cause of standing water (e.g. grade depressions, comapcted soil) is addressed. Vegetation Plant Survival Dispersal areas vegetation in establishment period (1-2 years, or additional 3rd year) during extreme dry weather. Vegetation is health and watered weekly during periods of no rain to ensure plant establishment. Vegetation Lack of Vegetation Allowing Erosion Poor vegetation cover such that erosion is occuring. Vegetation is healthy and watered. No eroded or scoured areas are present. Cause of erosion or scour is addressed. Plant species are appropriate for the soil and moisture conditions. Vegetation Vegetation Blocking Flow Vegetation inhibits dispersed flow along flow path. Vegetation is trimmed, weeded, or replanted to restore dispersed flow path. Vegetation Presence of Noxious Weeds Anynoxious or nuisance vegetation which may constitute a hazard to county personnel or the public. Noxious and nuisance vegetation removed according to applicable regulations. No danger of noxious vegetation where county personnel or the public might normally be. Pest Control Mosquito Infestation Standing water remains for more than three days following storms. All inlets, overflows, and other openings are protected with mosquito screens. No mosquito infestation present. Rodents Presence of Rodents Rodent holes or mounds disturb dispersion flow paths. Rodents removed or destroyed, holes are filled, and flow path is revegetated. ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 31 #22 – Maintenance Checklist for Conveyance Systems (Pipes and Ditches): Drainage System Feature Defect or Problem Condition When Maintenance is Needed Results Expected When Maintenance is Performed Pipes Sediment and Debris Accumulated sediment that exceeds 20 percent of the diamter of the pipe. Pipe cleaned of all sediment and debris. Pipes Vegetation Vegetation that reduces free movement of water through pipes. Vegetation does not impede free movement of water through pipes. Prohibit use of sand and sealant application and protect from construction runoff. Pipes Damaged (Rusted, Bent, or Crushed) Protective coating is damaged: rust is causing more than 50 percent deterioration to any part of pipe. Pipe repaired or replaced. Pipes Damaged (Rusted, Bent, or Crushed) Any dent that significantly impedes flow (i.e. decreases the cross section area of pipe by more than 20 percent). Pipe repaired or replaced. Pipes Damaged (Rusted, Bent, or Crushed) Pipe has major cracks or tears allowing groundwater leakage. Pipe repaired or replaced. Open Ditches Trash and Debris Dumping of yard waste such as grass clippings and branches. Unsigtly accumulation of non- degradable materials such as glass, plastic, metal, foam, and coated paper. No trash or debris present. Trash and debris removed and disposed of as prescribed by the County. Open Ditches Sediment Buildup Accumulated sediment that exceeds 20 percent of the design depth. Ditch cleaned of all sediment and debris so that it matches design. Open Ditches Vegetation Vegetation (e.g. weedy shrubs or saplings) that reduces free movements of water through ditches. Water flows freely through ditches. Grassy vegetaiton should be left alone. Open Ditches Erosion Damage to Slopes Erosion damage over 2 inches deep where cause of damage is still present or where there is potential for continued erosion. No erosion damage present. Slopes stabilized using appropriate erosion control measure(s), e.g., rock reinforcement, planting of grass, compaction. Open Ditches Erosion Damage to Slopes Any erosion observed on a compacted berm embankment. If erosion is occuring on compacted berms a professional engineer should be conculted to resolve source or erosion. Open Ditches Rock Lining Out of Place or Missing (If Applicable) Native soil is exposed beneath the rock lining. Rocks replaced to design standards. ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 32 Appendix B ”Covenant of Declaration” ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 33 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 34 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 35 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 36 ---PAGE BREAK--- October 3, 2017 17-172 Devore Rd.DP.TIR Page 37 Appendix C ”WWHM” ---PAGE BREAK--- WWHM2012 PROJECT REPORT ---PAGE BREAK--- 17-172 10/3/2017 2:34:38 PM Page 2 General Model Information Project Name: 17-172 Site Name: Devore Red Site Address: 11235 - 165th Ct NE City: Report Date: 10/3/2017 Gage: Seatac Data Start: 1948/10/01 Data End: 2009/09/30 Timestep: 15 Minute Precip Scale: 1.000 Version Date: 2017/04/14 Version: 4.2.13 POC Thresholds Low Flow Threshold for POC1: 50 Percent of the 2 Year High Flow Threshold for POC1: 50 Year ---PAGE BREAK--- 17-172 10/3/2017 2:34:38 PM Page 3 Landuse Basin Data Predeveloped Land Use Basin 1 Bypass: No GroundWater: No Pervious Land Use acre C, Forest, Mod 0.2 Pervious Total 0.2 Impervious Land Use acre Impervious Total 0 Basin Total 0.2 Element Flows To: Surface Interflow Groundwater ---PAGE BREAK--- 17-172 10/3/2017 2:34:38 PM Page 4 Mitigated Land Use Basin 1 Bypass: No GroundWater: No Pervious Land Use acre C, Lawn, Mod 0.11198 Pervious Total 0.11198 Impervious Land Use acre ROOF TOPS FLAT 0.08802 Impervious Total 0.08802 Basin Total 0.2 Element Flows To: Surface Interflow Groundwater ---PAGE BREAK--- 17-172 10/3/2017 2:34:38 PM Page 5 Routing Elements Predeveloped Routing ---PAGE BREAK--- 17-172 10/3/2017 2:34:38 PM Page 6 Mitigated Routing ---PAGE BREAK--- 17-172 10/3/2017 2:34:38 PM Page 7 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area: 0.2 Total Impervious Area: 0 Mitigated Landuse Totals for POC #1 Total Pervious Area: 0.11198 Total Impervious Area: 0.08802 Flow Frequency Method: Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.001166 5 year 0.002923 10 year 0.004774 25 year 0.008119 50 year 0.011491 100 year 0.015751 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.04051 5 year 0.055333 10 year 0.066027 25 year 0.080571 50 year 0.092174 100 year 0.104451 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.004 0.062 1950 0.004 0.057 1951 0.001 0.034 1952 0.001 0.025 1953 0.000 0.027 1954 0.001 0.033 1955 0.001 0.037 1956 0.003 0.036 1957 0.001 0.044 1958 0.002 0.031 ---PAGE BREAK--- 17-172 10/3/2017 2:35:13 PM Page 8 1959 0.001 0.028 1960 0.001 0.033 1961 0.001 0.035 1962 0.000 0.027 1963 0.001 0.036 1964 0.002 0.032 1965 0.002 0.048 1966 0.001 0.026 1967 0.004 0.055 1968 0.002 0.059 1969 0.001 0.043 1970 0.001 0.038 1971 0.001 0.047 1972 0.003 0.057 1973 0.000 0.023 1974 0.002 0.046 1975 0.002 0.045 1976 0.001 0.033 1977 0.001 0.033 1978 0.001 0.039 1979 0.000 0.050 1980 0.009 0.066 1981 0.001 0.040 1982 0.002 0.064 1983 0.001 0.044 1984 0.001 0.030 1985 0.000 0.042 1986 0.001 0.033 1987 0.002 0.050 1988 0.000 0.028 1989 0.000 0.036 1990 0.014 0.102 1991 0.005 0.073 1992 0.001 0.029 1993 0.000 0.024 1994 0.000 0.024 1995 0.002 0.036 1996 0.005 0.048 1997 0.001 0.041 1998 0.001 0.035 1999 0.010 0.094 2000 0.001 0.042 2001 0.000 0.039 2002 0.002 0.056 2003 0.005 0.048 2004 0.002 0.084 2005 0.001 0.035 2006 0.001 0.032 2007 0.010 0.092 2008 0.007 0.070 2009 0.001 0.044 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.0144 0.1018 2 0.0099 0.0943 3 0.0096 0.0925 ---PAGE BREAK--- 17-172 10/3/2017 2:35:13 PM Page 9 4 0.0091 0.0837 5 0.0068 0.0734 6 0.0055 0.0702 7 0.0055 0.0660 8 0.0045 0.0638 9 0.0040 0.0623 10 0.0038 0.0587 11 0.0038 0.0573 12 0.0031 0.0566 13 0.0027 0.0565 14 0.0022 0.0553 15 0.0020 0.0504 16 0.0019 0.0500 17 0.0018 0.0482 18 0.0018 0.0480 19 0.0018 0.0477 20 0.0018 0.0468 21 0.0017 0.0461 22 0.0015 0.0445 23 0.0015 0.0440 24 0.0015 0.0437 25 0.0015 0.0435 26 0.0014 0.0430 27 0.0012 0.0421 28 0.0012 0.0419 29 0.0012 0.0408 30 0.0012 0.0405 31 0.0011 0.0395 32 0.0011 0.0388 33 0.0011 0.0377 34 0.0011 0.0367 35 0.0010 0.0363 36 0.0010 0.0360 37 0.0010 0.0356 38 0.0010 0.0355 39 0.0009 0.0354 40 0.0009 0.0352 41 0.0008 0.0347 42 0.0008 0.0340 43 0.0007 0.0333 44 0.0007 0.0330 45 0.0007 0.0329 46 0.0006 0.0329 47 0.0006 0.0325 48 0.0005 0.0324 49 0.0005 0.0324 50 0.0005 0.0314 51 0.0005 0.0301 52 0.0003 0.0294 53 0.0003 0.0285 54 0.0003 0.0284 55 0.0003 0.0272 56 0.0003 0.0268 57 0.0002 0.0260 58 0.0002 0.0246 59 0.0002 0.0239 60 0.0002 0.0237 61 0.0002 0.0233 ---PAGE BREAK--- 17-172 10/3/2017 2:35:13 PM Page 10 ---PAGE BREAK--- 17-172 10/3/2017 2:35:13 PM Page 11 Duration Flows Flow(cfs) Predev Mit Percentage Pass/Fail 0.0006 236 195387 82791 Fail 0.0007 186 181527 97595 Fail 0.0008 152 169742 111672 Fail 0.0009 119 159411 133958 Fail 0.0010 108 150492 139344 Fail 0.0011 92 142599 154998 Fail 0.0012 77 135220 175610 Fail 0.0014 69 128589 186360 Fail 0.0015 61 122429 200703 Fail 0.0016 54 116847 216383 Fail 0.0017 48 111628 232558 Fail 0.0018 46 106687 231928 Fail 0.0019 40 102260 255650 Fail 0.0020 35 98025 280071 Fail 0.0021 31 94111 303583 Fail 0.0022 30 90389 301296 Fail 0.0023 30 86774 289246 Fail 0.0025 28 83331 297610 Fail 0.0026 27 80037 296433 Fail 0.0027 26 76978 296069 Fail 0.0028 24 73984 308266 Fail 0.0029 22 71182 323554 Fail 0.0030 22 68423 311013 Fail 0.0031 20 65920 329600 Fail 0.0032 19 63418 333778 Fail 0.0033 18 61065 339250 Fail 0.0034 18 58841 326894 Fail 0.0036 18 56744 315244 Fail 0.0037 18 54606 303366 Fail 0.0038 18 52638 292433 Fail 0.0039 16 50777 317356 Fail 0.0040 15 49002 326680 Fail 0.0041 15 47312 315413 Fail 0.0042 15 45644 304293 Fail 0.0043 15 44040 293600 Fail 0.0044 14 42478 303414 Fail 0.0045 13 41066 315892 Fail 0.0047 13 39698 305369 Fail 0.0048 12 38286 319050 Fail 0.0049 12 36938 307816 Fail 0.0050 12 35634 296950 Fail 0.0051 12 34479 287325 Fail 0.0052 12 33345 277875 Fail 0.0053 12 32190 268250 Fail 0.0054 12 31121 259341 Fail 0.0055 10 30115 301150 Fail 0.0057 8 29132 364150 Fail 0.0058 8 28190 352375 Fail 0.0059 8 27271 340887 Fail 0.0060 8 26351 329387 Fail 0.0061 8 25495 318687 Fail 0.0062 8 24661 308262 Fail 0.0063 8 23870 298375 Fail 0.0064 8 23079 288487 Fail ---PAGE BREAK--- 17-172 10/3/2017 2:35:13 PM Page 12 0.0065 8 22351 279387 Fail 0.0066 8 21645 270562 Fail 0.0068 8 20950 261875 Fail 0.0069 7 20317 290242 Fail 0.0070 7 19663 280900 Fail 0.0071 7 19068 272400 Fail 0.0072 7 18497 264242 Fail 0.0073 7 17947 256385 Fail 0.0074 7 17406 248657 Fail 0.0075 7 16867 240957 Fail 0.0076 7 16377 233957 Fail 0.0077 7 15864 226628 Fail 0.0079 7 15408 220114 Fail 0.0080 7 14910 213000 Fail 0.0081 7 14497 207100 Fail 0.0082 7 14048 200685 Fail 0.0083 7 13659 195128 Fail 0.0084 7 13246 189228 Fail 0.0085 7 12910 184428 Fail 0.0086 7 12566 179514 Fail 0.0087 6 12202 203366 Fail 0.0088 6 11896 198266 Fail 0.0090 6 11565 192750 Fail 0.0091 6 11218 186966 Fail 0.0092 5 10876 217520 Fail 0.0093 5 10551 211020 Fail 0.0094 5 10245 204900 Fail 0.0095 4 9967 249175 Fail 0.0096 4 9713 242825 Fail 0.0097 3 9428 314266 Fail 0.0098 3 9176 305866 Fail 0.0099 2 8947 447350 Fail 0.0101 2 8733 436650 Fail 0.0102 2 8493 424650 Fail 0.0103 2 8286 414300 Fail 0.0104 2 8055 402750 Fail 0.0105 2 7818 390900 Fail 0.0106 2 7589 379450 Fail 0.0107 2 7379 368950 Fail 0.0108 2 7176 358800 Fail 0.0109 2 6966 348300 Fail 0.0111 2 6782 339100 Fail 0.0112 2 6609 330450 Fail 0.0113 2 6440 322000 Fail 0.0114 2 6271 313550 Fail 0.0115 2 6113 305650 Fail The development has an increase in flow durations from 1/2 Predeveloped 2 year flow to the 2 year flow or more than a 10% increase from the 2 year to the 50 year flow. The development has an increase in flow durations for more than 50% of the flows for the range of the duration analysis. ---PAGE BREAK--- 17-172 10/3/2017 2:35:13 PM Page 13 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume: 0 acre-feet On-line facility target flow: 0 cfs. Adjusted for 15 min: 0 cfs. Off-line facility target flow: 0 cfs. Adjusted for 15 min: 0 cfs. ---PAGE BREAK--- 17-172 10/3/2017 2:35:13 PM Page 14 LID Report ---PAGE BREAK--- 17-172 10/3/2017 2:35:37 PM Page 15 Model Default Modifications Total of 0 changes have been made. PERLND Changes No PERLND changes have been made. Changes No changes have been made. ---PAGE BREAK--- 17-172 10/3/2017 2:35:37 PM Page 16 Appendix Predeveloped Schematic ---PAGE BREAK--- 17-172 10/3/2017 2:35:37 PM Page 17 Mitigated Schematic ---PAGE BREAK--- 17-172 10/3/2017 2:35:37 PM Page 18 Predeveloped UCI File ---PAGE BREAK--- 17-172 10/3/2017 2:35:37 PM Page 19 Mitigated UCI File ---PAGE BREAK--- 17-172 10/3/2017 2:35:37 PM Page 20 Predeveloped HSPF Message File ---PAGE BREAK--- 17-172 10/3/2017 2:35:37 PM Page 21 Mitigated HSPF Message File ---PAGE BREAK--- 17-172 10/3/2017 2:35:37 PM Page 22 Disclaimer Legal Notice This program and accompanying documentation is provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. Clear Creek Solutions, Inc. disclaims all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions, Inc. be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions, Inc. has been advised of the possibility of such damages. Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com