Document Millcreek_doc_eaf1007def

Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 1 18.51 Sensitive Lands 18.51.010 Purpose and Intent A. To preserve the distinctive features and the natural setting of the City and to promote development that recognizes and respects the character of the land. B. To identify and document sensitive lands that shall be protected from development and to guide sensitive lands related open space designations in development proposals. C. To identify certain hazardous conditions that require buffering, avoidance, or other engineering techniques to allow for safe beneficial development. D. To provide for the health, safety, welfare of the citizens, as well as protect urban and nonurban development, the good order and aesthetics of our municipality, and protection of property values as set forth in Utah Code Ann. §10-9a-102(1). 18.51.020 Applicability A. A Sensitive Lands Area is defined as any area that is either: 1. located within the affected areas identified on the Sensitive Lands Map, adopted and amended from time to time by the Millcreek City Council; or 2. Contains sensitive lands features as described in this section 3. Affected by geological hazards identified in a geotechnical report, a topographical survey, or soils study. B. Any land use application for development located in a Sensitive Lands Area including but not limited to, building permits for a new structure or existing structures that add additional square footage to the primary or secondary structure, permitted and conditional uses, preliminary and final subdivision plats, shall include a sensitive lands identification analysis addressing the requirements of this chapter through a Geotech report that identifies/analyzes not only geologic hazards but also the other sensitive lands features as described in this chapter. C. Geotech or other required reports shall be provided by the applicant based on the Sensitive Lands map, or if a property is determined to be in a Sensitive Lands Area by a previous geotechnical report, topographical survey, or soils study. The required reports are shown in Table X and such reports will vary based on the severity and type of sensitive lands found within the proposed development. In addition, see corresponding engineering checklists. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 2 D. The City retains a City Geologist for review, analysis, to suggest modifications, and approval of the reports. Any costs incurred for the City Geologist which may include contracted specialized engineering, geotechnical services, site inspection, testing, and review time due to the proposed development will be passed along to the applicant or developer and deposited with the City. Such costs shall be based on an estimate provided by the City Geologist, a subsequent full deposit by the applicant/developer of the estimate cost plus 20%. Unused funds shall be returned to the applicant, without interest. E. Existing properties located in low liquefaction potential areas and have slope angles less than 15% may be exempt from the full Geotech report requirements, but shall provide soil type and depth to the water table information to assure foundation suitability. Such reports are not required for fences but are required for any retaining wall or accessory building over 200 square feet when located in a Sensitive Lands Area F. Any sensitive lands identified as a result of the requirements of this chapter shall be recognized in the development proposal. Some sensitive lands can not be mitigated and as such, development design shall avoid and preserve as undevelopable the identified sensitive lands areas. Such lands shall be designated on the site plan or plat in a manner that permanently restricts the area from development. G. A grading plan and the limits of disturbance shall accompany any development plan in a sensitive land area. Limits of disturbance shall be defined by the least area needed to construct the development, required setbacks on the site, a prescribed buffer area if located in the Wildland Urban Interface, and the avoidance of any unmitigable sensitive lands. Limits of Disturbance are further described in MKZ 18.51.070 H. Notwithstanding the spatial requirements established an any underlying zone, additional lot coverage limits, setbacks, or other spatial requirements may be required in a Sensitive Lands Area, due to the requirements of this chapter. 18.51.030 Sensitive Lands Description A. Sensitive Lands contain characteristics that can influence, modify, or limit development patterns through physical or regulatory restrictions. Sensitive lands features covered by this chapter, are described as: 1. Topographical Features: The types of lands represented in this typology include slopes over 15 percent wetlands, rock outcroppings larger than 10 feet (10’) wide and 10 feet (10’) tall, avalanche zones, alluvial fans, rock fall areas, gullies/ravines deeper than 10 feet (10)and wider than 20 feet intermittent or constant flow stream corridors, ridgelines, springs, species protection, Wildland Urban Interfaces, and floodplains. Additional requirements for floodplains are found in MKZ 18.XX. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 3 2. Subsurface Features: Soils, saturated soils, and soil structures such as, areas of liquefaction potential, surface fault rupture hazard areas, and debris flow areas. Soil types to determine surface stability, foundation stability, movement potential, depth to bedrock, and shallow water table levels, may also reveal factors to consider for avoidance/preservation and/or design modifications when determining the extent of sensitive lands. 18.51.040 Identification Required Designation and possible preservation or avoidance of the identified Sensitive Lands features and their associated area(s) in their natural state is required. A Sensitive Lands Geotech report is required for lands located in the Sensitive Lands Map or where a Geotech report identifies sensitive lands issues. A Sensitive Land Area shall be shown in concept plans, existing properties, site plans, preliminary and final subdivision plats. It is the intent of these requirements to promote a development design that incorporates and integrates the sensitive lands into the development design process as valued aspects of that design. These characteristics need identification and are significant factors that determine how sensitive lands should be reflected in the design of a particular development site. Sensitive lands features shall be shown on the development site plan and detailed by the appropriate study, as required by this Chapter. 18.51.050 Remediation for Mitigatable Sensitive Lands Certain Sensitive Lands have the potential to be remediated and/or mitigated. Determinations and mitigation techniques proposed that, when reviewed by the City Engineer and City Geologist, do not clearly resolve any identified issues may be subject to a Peer Review at the City’s discretion. The process for a Peer Review is set forth in MKZ 18.51.060. The City Engineer and City Geologist shall have the right to review, provide comments and suggested changes, and ultimately approve, deny, or modify the mitigation techniques. Such mitigation techniques shall be stamped by the applicant’s geotechnical engineer. All disturbed lands shall be rehabilitated and revegetated, except where buildings and impervious surfaces are proposed on the approved site plan or subdivision plat. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 4 18.51.060 Dispute Resolution and Peer Review When the City Geologist and City Engineer determine that a third party review of the information provided by the developer/applicant is appropriate or that additional studies are needed, the developer shall pay for such additional studies/Peer Reviews and the City shall manage the funds. Such costs shall be based on an estimate provided by an engineer and/or geologist of the City’s choosing, a subsequent full deposit by the applicant/developer of the estimate cost plus 20 percent Drawdowns may be approved by the City as work is completed leading to a final report. Unused funds shall be returned to the applicant, without interest. Such studies or peer reviews may be required for any identified sensitive land. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 5 18.51.070 Development Design Considerations A. Grading Plan Required. All development plans in a Sensitive Lands Area shall include a grading plan, subject to the requirements for Engineering Grading Plans as set forth in the Engineering Requirements Checklist , to assure that the development minimizes land disturbance, that erosion and stormwater are retained on-site to the greatest extent possible, and conforms to Title 14, Engineering Standards. Topsoil that is removed from the site during construction shall be conserved for later use on areas requiring revegetation or landscaping, such as cut-and-fill slopes. Such plans shall establish a limit of disturbance indication on the site plan where development activity will be contained. Sites with slopes that average over 20% shall limit their grading to no more than 60% of the lot area. B. Limits of Disturbance. The limits of disturbance (LOD) is defined as the area(s) in which construction and development activity shall be contained, including development and construction of the principal building, accessory structures, recreation areas, utilities, services, driveways, storm drainage, and other similar improvements. LOD areas shall not encroach into setbacks required by the underlying zone or the specified buffers as defined in this chapter. An LOD Site Plan Example is illustrated in Figure 18.51.XX. 1. Exclusions from Limits of Disturbance. The following need not be included in the limits of disturbance: a. Up to ten (10) feet of paved or unpaved shoulders for driveways. b. Areas consisting of natural ponds, streams, trees, and other vegetation where no grading work is done. Such areas shall be avoided, buffered, and/or preserved. 2. Updates to Limits of Disturbance. LODs may be required to be updated during the construction process, due to unforeseen circumstances. In the case of an amendment, a revised LOD shall be submitted to the City for a site plan review. 3. Delineation of Limits of Disturbance On Site. An LOD shall be delineated on site with fencing or other separation methods approved by the Planning Director prior to the commencement of excavation, grading, or construction activities on the site. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 6 Figure 18.51.XX – LOD Site Plan Example. C. Slope Cuts and Grading. Slope cuts and grading shall conform to the following: 1. Prior to issuance of a building permit, final plans shall be in accordance with a grading and excavation plan and the Geotech report for the site, as approved by the City Engineer. Figure 18.51.XX illustrates a development plan that minimizes cuts. 2. Cantilevers/eaves located on a second floor and above may encroach into the LOD and/or zone setbacks by up to three feet, provided the cantilevered setback can be constructed entirely from within the LOD. Figure 18.51.XX – A Development Plan that Minimizes Cuts ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 7 3. The original, natural grade of a lot may not be raised or lowered more than four feet at any point for construction of any structure or improvement, except that the site’s original grade may be raised or lowered eight feet if a retaining wall or terracing is used to reduce the steepness of man-made slopes. Terraces and retaining walls must comply with the requirements of MKZ 18.XX – Fencing, Walls, and Retaining Walls. 4. Separate building pads for accessory buildings other than private garages, (including but not limited to accessory dwelling units, guest houses, barns, recreational structures such as tennis courts, swimming pools, and similar facilities) are prohibited except where the natural/original slope is twenty percent (20%) or less. 5. The following limits apply to graded or filled human-caused slopes: a. Slopes of twenty-five percent (25%) or less are encouraged wherever possible. b. Graded or filled man-made slopes may not exceed the maximum slope supported by a geotechnical study and constructed per the geotechnical engineers requirements not to exceed fifty percent c. Cut man-made surfaces or slopes may not exceed a slope of fifty percent (50%) unless it is substantiated, on the basis of a site investigation and submittal of a soils engineering or geotechnical report prepared and certified by a qualified professional, that a cut on a steeper slope will be stable and will not create a hazard to public or private property. d. All cut, filled, and graded slopes shall be re-contoured to the natural, varied contour of the surrounding terrain. e. Stormwater retention or detention is prohibited on slopes greater than 25 percent 6. Excavation for footings and foundations shall not occur outside limits of disturbance and shall minimized to lessen site disturbance and ensure compatibility with hillside and sloped terrain. Intended excavation must be supported by detailed engineering plans submitted as part of the application for site plan approval. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 8 D. Stormwater. Storm drainage plans shall include a system design to return collected and clarified waters to the natural drainage channels or to the adjacent ground, as set forth in MKC 17.22.050. All developments are required to obtain a Land Disturbance and Stormwater Quality Permit (LDP) as set forth in MKZ 17.22.040 and if required shall provide evidence of a Utah State Department of Environment Quality General Construction Storm Water UPDES Permits at building permit issuance. Soils Conditions. Geotech reports, are required as set forth in MKZ 18.51.020 and in the Engineering Requirements Checklist and are catered to the type of Sensitive Lands encountered, shall also include an analysis of the soil types and their potential for movement when additional moisture is applied, as may occur from heavy rainfall or melting snow, landscape irrigation and/or impervious surface runoff or saturation, on any lot with a slope over 15 percent Geotech reports shall also identify the depth to water table, and potential fluctuations in seasonal water tables, if buildings with basements are to be constructed within the proposed development. In the absence of a year-long analysis of water table fluctuations, the time period to be studied is from March 15 to June 15 and such fluctuations may be estimated if the timing of such studies is contrary to the development schedule. Additional requirements for drainage of subsurface water are set forth in MKC 17.12. E. Trails. After identifying/documenting (or delineating in the case of wetlands) any sensitive lands as defined above, and reviewing the Millcreek Sidewalk and Trails Master Plan, the Millcreek General Plan, the Salt Lake County Regional Trails Master Plan, as part of the design process of a development, and as part of the concept plan submission, each development shall include a conceptual design to assess how the development will be designed to preserve the identified sensitive lands and evaluate the potential to extend trail systems to and within the area. Trails are designated a conditional use on slopes up to 50 percent prohibited from areas sloped greater than 50 percent and may disturb areas they traverse. F. Mitigating Cuts and Fills. Development shall mitigate the visibility of cuts and fills and buildings on hillsides that are visible from the adjacent streets. Mitigations shall include methods to conceal such cuts and fills and buildings, such as evergreen landscaping, hill terracing, use of earth-tone colors on structures, or the reduction of the width of a required street cross-section, subject to approval of the City Engineer or Fire Marshal. 18.51.080 Development Limitations and Prohibitions A. All new development, including any subdivision of land, shall avoid and preserve as undisturbed/natural open space, the following areas: 1. Slopes 30% or greater: Except for the installation of fencing and live plant materials, development is prohibited on slopes of 30 percent (30%) or greater. Slopes of 30 percent (30%) or greater shall remain undisturbed, ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 9 unless a property has a natural, contiguous building area based on the original grade that can encompass the proposed building, and has a buildable area with a minimum of five thousand (5,000) square feet at or below thirty percent (30%) natural grade. All such properties shall include specific engineering designs to contain runoff, erosion, and pollution on the subject property during construction and after construction. A Limit of Disturbance, , land disturbance permit, and possibly a permit are required. This includes the prevention of any materials caused by erosion flowing out onto adjacent trails, sidewalks and streets, adjacent fences/properties, and erosion onto the sensitive lands buffer areas. Additional setbacks from sections of the property that are steeper may be required as per the Geotech report, or as identified in adopted building codes. Where slope maps are required as part of a Geotech report, they shall include: a. A base topographical map of the subject site, prepared and signed by a Utah licensed civil engineer or land surveyor. This base topographical map shall include all adjoining properties within one hundred fifty feet (150') of the site boundaries to portray the site's context. b. This slope analysis shall be prepared using CAD based or GIS based software specifically designed for such purpose. Contours on the exhibits shall be prepared using no greater than two-foot contour intervals with ten foot (10') contours being clearly labeled and at a scale of not less than one inch equals one hundred feet = 100'). The slope analysis exhibit shall delineate slope bands, with contrasting colors, for the following slope ranges: zero percent to fifteen percent 15.01 percent to twenty five percent 25.01 percent to thirty percent 30.01 percent to fifty percent and 50.01 percent or greater. c. A tabulation chart indicating the land area in acres within each slope category as identified herein. d. A sufficient number of slope cross sections to clearly illustrate the extent of the proposed grading. The slope cross sections shall: ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 10 Be drawn at the same scale and indexed, or keyed, to the existing topography, grading plan, and project site map. Both vertical and horizontal scales shall be indicated and be of the same scale. The slope cross section shall extend at least one hundred fifty feet (150') outside the project site boundary to clearly show impact on adjacent property. Slopes shall be calculated in intervals no greater than forty feet (40') along the cross sections. At a minimum, sections shall be drawn along those locations of the project site where: The greatest alteration of existing topography is proposed; The most intense or massive development is proposed; The site is most visible from surrounding land uses; Where grading will impact natural drainage conditions. At least two of the slope profiles shall be roughly parallel to each other and roughly perpendicular to existing contour lines. The slope cross sections shall be stamped and signed by a Utah licensed professional proficient in creating such cross sections indicating the datum, source, and scale of topographic data used in the slope profiles. The signer shall attest to the fact that the slope profiles have been accurately calculated and identified. The slope cross sections shall show existing and proposed topography, structures, driveways, and roadways. Proposed topography and features shall be drawn with a solid line. Existing topography and features shall be drawn with a dashed line. e. The slope analysis calculations shall be prepared by a Utah licensed professional who is proficient in creating the exhibits with the use of computer software designed for preparing said exhibits. 2. Cuts and fills shall be avoided in project design to the greatest extent possible and shall not exceed fifty percent (50%) slope. Retaining walls extending over six feet in height shall include a level landscaped terrace, a minimum of six feet in width for every six feet in height, as illustrated in Figure 18.51,XX. Terraces may be created at lesser heights to meet slope related issues, but the minimum terrace width shall be in six-foot intervals. Development affecting slopes of 20 percent (20%) or greater shall submit plans that conform to any City Standards, utilize Low Impact Development techniques, and may require specialized storm water permits such as a Revegetation with native plants and groundcovers of ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 11 disturbed areas is required as soon as possible or within 6 months for any grading performed for road work and after the occupancy of a home. Streets, roads, alleys, or driveways may not cross slopes that average (in any fifty foot interval) 30 percent or greater. Public or private streets in a sensitive land area shall not exceed 12 percent Driveways or private streets shall not exceed ten percent (10% )within 20’ of a public street. Figure 18.51.XX Cut and Fill Example Cut and fill example 3. Avalanche paths: Avalanche paths shall be identified, and development shall avoid such paths as recommended by a qualified Geotechnical Engineer. 4. Fault lines, scarps, landslides, rock outcroppings, rock-fall, alluvial, fans and mud/debris flow areas: These topographical features shall be avoided and mitigated as recommended by a qualified Geotechnical Engineer. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 12 Figure 18.51.XX Buffer Example 5. Stream beds (including intermittent), gullies, ditches, flood channels, flood plains, areas of springs, seeps and surface water: Pollution sources including but not limited to fuel tanks and their containment systems, animal yards, septic tanks, parking lots, shall be setback at least 50 feet from the hydrologic feature or as required by the Utah Department of Water a. Additional vegetation may be required between the hydrologic features and development for erosion control (with limited fertilizer or pesticide use in natural corridors) or for public amenities. Hydrologic features that are accompanied by an amenity such as a park or trail shall include sufficient open area along and surrounding the hydrologic feature to ensure ample room to protect the feature and to provide area for enjoyment of the amenity; generally such buffering/setback from a building, should be an average of 50 feet from the top edge of the bank or high water mark of the feature of a perennial stream and 50’ from any other feature mentioned above, as illustrated in Figure 18.51.XX, unless otherwise specified in Title 14 or supported through a geotechnical engineer’s study. Such areas are not allowed to be filled/eliminated. b. Any development within a floodplain shall comply with the standards and permitting requirements of MKZ 18.XX Floodplain Hazard Regulations and MKC Title 17 Flood Control and Water Quality. 6. Canals. Development shall avoid destabilizing the downhill portion of canals. No cuts shall be permitted below a fifty percent (50%) slope measured from the downhill bank of a canal without mitigation/safety strategies proposed by ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 13 a geotechnical engineer, as illustrated in Figure 18.51.XX below. Construction adjacent to a canal shall be coordinated with the facility/canal owner and is subject to review and approval by the owner of the facility. Construction adjacent to a canal shall allow inspections by the facility owner during construction and when construction is complete the facility owner shall provide a letter of acceptance. Figure 18.51.XX Canal Bank Stabilization 7. Identified wetlands: Identified wetlands shall be delineated using the Section 404 definition and procedures as set forth in the Clean Water Act. Protected wetlands shall be accompanied by additional open lands when they are adjacent or combined with usable open space and trails, with such adjacent areas averaging a width of 50 feet wide from the defined edge of the wetland. Pollution sources such as fuel tanks and their containment systems, parking lots, etc. shall be set back 100 feet (100’) from the identified wetlands, unless diversionary devices, as recommended by a Geotechnical engineer, and approved by the City, are constructed to solve potential pollution problems. Additional vegetation may be required in these buffer areas for erosion control (with limited fertilizer or pesticide use) or for public amenities, to reduce the illicit discharges as set forth in MKC 17.22.130. 8. Wildfire Potential: Potential wildfire areas shall be assessed, and mitigation strategies applied, as per the best practices of the Utah Wildland Urban Interface Code (WUI). Best practices suggest, low fire hazard buffers surrounding lots and/or buildings in areas to be developed that are prone to wildfires. A specific plan addressing mitigating measures to reduce the potential for damage from wildfires is required. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 14 9. Ridgelines. Unless otherwise allowed by this title, no development may break a ridgeline. In addition to reidgelines as defined in this Title, for the purposes of this chapter, ridgelines also include ridges that are visible as viewed from the ground level within the Wasatch Boulevard right-of-way. 18.51.090 Development Constraints for Certain Sensitive Lands A. The following sensitive lands with potential hazards require additional mitigation techniques in any new development, including the subdivision of land, and the developer shall provide mitigation for such hazards when they apply. The City requires Geological hazards disclosure and acknowledgment and acknowledgement of any associated geologic hazard site-specific studies to be recorded on the Title for the property, or on the subdivision plat. A Geological hazards disclosure and acknowledgement shall be on a form provided by the City. . Such mitigatable hazards and mitigation techniques (practicable or available) shall include, but are not limited to the following: 1. Alluvial fan, flood/debris flow, liquefaction potential, collapsible soils, and shrink-swell soils. Mitigation techniques shall follow the advisement of a qualified Geotechnical Engineer and may be subject to peer review, at the developer’s cost. 2. Shallow groundwater. Areas with ground water within 3’ of the ground surface, shall require additional analysis to assess their feasibility for development. If areas of shallow ground water are found that prohibit or impact foundations, such areas shall be noted in the concept design (if required) and carried forward on the preliminary and final plats. Possible mitigation techniques include the installation of a foundation drain and sump pump possible prohibition of basements, or other mitigation techniques as provided on the advisement of a qualified Geotechnical Engineer. 3. 100-year flood zones. Mitigation techniques shall follow the procedures of MKZ XX, Floodplain Hazard Regulations Ordinance. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 15 18.51.100 Geotech/Geologic Hazard And Engineering Geology Reports. A. In addition to the checklists required by the City through Engineering and Planning, this section describes requirements for site-specific geologic hazard studies and reports. If the report conclusions are questioned, they may be subject to a Peer Review as set forth in MKZ 18.51.060. This requirement is based on other previously mapped geo-hazards that are shown on the Sensitive Lands Map. Identified Sensitive Lands Areas are based on previous area studies and mapping that designated certain areas of the City to have potential geo-hazards or sensitive lands. All Geotech reports shall include a soil type, condition, percolation test, and water table analysis. Certain studies require an analysis method which shall follow the section below the table.. Some areas have more than one hazard or sensitive land feature that generates the need for certain studies, including: Sensitive Lands features - See sensitive lands map Geotech Report Level 1 Geotech Report Level 2 Liquefaction Analysis WUI prevention report Other Reports Surface Fault Rupture NA Yes No No Low Liquefaction Potential No No No No Moderate Liquefaction Potential Yes No Yes No High Liquefaction Potential No Yes Yes No Landslide, Debris Flow, rockfall, rock outcroppings No Yes No No Avalanche No Yes No No Slopes from 20% to 30% Slopes over 30% No Yes No No Shallow Water Table No Yes Yes No Flood Zone using FEMA A and AE Flood Zone maps No Yes Yes No Stream Corridor including intermittent streams, springs, No Yes Yes No ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 16 Sensitive Lands features - See sensitive lands map Geotech Report Level 1 Geotech Report Level 2 Liquefaction Analysis WUI prevention report Other Reports and other water bodies Saturated or movement prone soils No Yes Yes No Alluvial Fans No Yes No Yes, if located next to wildlands Include landslide and debris flow analyses Wetlands No Delineate – see 19. 42.80 above) Yes No Gullies/ravines deeper than 10’ and wider than 20’ No Yes No No Wildland Urban Interface No No No Yes *The methods to be used in Geotech and Liquefaction studies for certain sensitive land features are detailed below: ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 17 1. A Geotech report that includes a geologic hazards investigation and assessment shall be prepared by a qualified engineering geologist, except as provided below. The report shall be site- specific and shall identify all known or suspected potential geologic hazards, originating on-site or off-site, whether previously mapped or unmapped, that may affect the particular property. All reports shall be signed and stamped by the preparer and include the qualifications of the preparer(s). 2. Fault rupture hazard reports shall contain all requirements as described in the document “Minimum Standards for Surface Fault Rupture Studies” published by Salt Lake County, and incorporated by reference. Fault study reports shall be prepared, signed, and stamped by a qualified engineering geologist. 3. Liquefaction analyses shall contain all requirements as stated in the document “Liquefaction: A Guide to Land Use Planning” published by Salt Lake County, and incorporated by reference to this ordinance. Liquefaction analyses shall be prepared by a qualified professional geotechnical engineer, and shall include the professional engineer’s original stamp and signature. 4. Debris flow hazard studies and reports shall include test pits or trench logs (scaled 1 inch to 5 feet), include estimates of the number and frequency of past events and their thicknesses, volume and maximum clast sizes; and include estimates of the recurrence, depth, and impact forces anticipated in future events. While debris flow hazard analyses may require contributions from hydrologists and engineers, the debris flow report shall be under the control of, and prepared by, a qualified engineering geologist. 5. Landslide reports shall be prepared in accordance with the Utah Geological Survey’s “Guidelines for Evaluating Landslide Hazards in Utah” (Hylland, 1996). Landslide reports shall be prepared, signed, and stamped by a qualified engineering geologist, and include the qualifications of the preparer. Slope stability or other analyses included in these reports shall include both static and dynamic conditions, and shall be prepared by a qualified professional geotechnical engineer licensed in the State of Utah, and shall include the professional engineer’s original stamp and signature. 6. Snow avalanche hazard reports shall be prepared in accordance with the document “Snow- Avalanche Hazard Analysis for Land Use Planning and Engineering” (Colorado Geological Survey Bulletin 49) or other appropriate references. Avalanche hazard reports must be prepared by an experienced avalanche expert, and shall include the avalanche expert’s qualifications to perform the study (such as their experience in performing similar studies). ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 18 7. Other geologic hazard or engineering geology reports shall be prepared in accordance with Utah Geological Survey Miscellaneous Publication M, “Guidelines for Preparing Engineering Geologic Reports in Utah.” All reports shall be signed by the preparer and include the qualifications of the preparer. Generally, these reports must be prepared, signed, and stamped by a qualified engineering geologist licensed in the State of Utah. However, reports co-prepared by a professional engineer must include the professional engineer’s original stamp and signature. 8. All reports for areas where a level 2 Geotech report is required, shall include, at a minimum: a. A 1:24,000-scale geologic map (with reference) showing the surface geology (including but not limited to landslides, alluvial fans, and fault scarps), bedrock geology (where exposed), bedding attitudes, faults or other structural features, and the locations of any geologic hazards. The map shall illustrate the proposed site modifications/mitigations relative to geological and natural hazards and/or geotechnical limitations that may impact the site. b. A detailed site map of the subject area showing any site-specific mapping performed as part of the geologic investigation, and including boundaries and features related to any geologic hazards, topography, and drainage. The site map must show the location and boundaries of the hazard(s), delineation of any recommended setback distances from hazard(s), and recommended location(s) for structures. Buildable and non-buildable areas shall be clearly identified. Scale shall be one inch equals two hundred feet or smaller. c. Trench logs that explore 2’ below the lowest proposed excavation or is specified in the special study requirements, and test pit logs (scale: 1 inch equals 5 feet, or smaller), boring logs (scale: 1 inch equals 5 feet, or smaller), aerial photographs, references with citations, and other supporting information, as applicable d. Conclusions that summarize the characteristics of the geologic hazards, and that address the potential effects of the geologic conditions and geologic hazards on the proposed development and occupants thereof in terms of risk and potential damage. e. Specific recommendations for additional or more detailed studies, as may be required to understand or quantify the hazard, evaluate whether mitigation measures are required, and evaluate mitigation options. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 19 f. Specific recommendations for avoidance or mitigation of the effects of the hazard(s), consistent with the purposes of this ordinance. Such recommendations may include areas for preservation where the hazards prevent development. Design or performance criteria for engineered mitigation measures and all supporting calculations, analyses, modeling or other methods, and assumptions, shall be included in the report. Final design plans and specifications for engineered mitigation must be signed and stamped by a qualified professional geotechnical or structural engineer, as appropriate. g. Evidence on which recommendations and conclusions are based, shall be clearly stated in the report. B. Additional or more detailed studies may be required, as recommended by the report or as determined by the City Geologist on behalf of the City, to understand or quantify the hazard, or to evaluate whether mitigation measures recommended in the report are adequate. 18.51.110 Review and Approval of Required Reports A. In order to fulfill the purposes of this chapter, city staff and the City Geologist shall review any proposed land use which requires preparation of a geotechnical and/or Sensitive Lands/geologic hazard report under this chapter and as shown on the Sensitive Lands Map to determine the possible risks to the safety of persons, property or City infrastructure from Sensitive Lands. B. Prior to consideration of any such development, the Geotech and/or geologic hazard report shall be delivered/submitted to the City Geologist on behalf of the City for review and recommendation. The City Geologist may request the Utah Geological Survey, the U.S. Forest Service, and/or other experts to review the report (third-party review) and provide additional recommendations. Any cost the City must pay for such third-party reviews shall be paid by the applicant before the review is complete. The City Geologist on behalf of the City shall file a copy of any report involving significant geologic hazards with the Utah Geological Survey, and another copy in the Planning Department project file. C. The City Geologist on behalf of the City and other retained experts in their review of the report, in consultation with the City Engineer and Planning Director, shall determine whether the development complies with all of the following standards: 1. A suitable geotechnical and/or geologic hazard report has been prepared by a qualified professional as defined above. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 20 2. The proposed land use shall not include land to be developed that encompasses unmitigable hazards, including buildings, storm drains and systems, culinary water facilities, public streets, utilities or critical facilities, whether off-site or on-site. Natural functions of the landscape (including but not limited to slopes, streams or other waterways, drainage, and wildlife habitat, whether off-site or on-site) shall be retained where the presence of geologic hazards or because of modifications to the site due to the proposed land use shall negatively impact such functions; 3. If the applicant submits substantial evidence in the Geotech/geologic hazard report that, using best available practices according to bona fide industry standards, including but not limited to AWWA, IBC, IFC, IRC, APWA, AASHTO, NFID, FEMA, WDDW, and UDEQ, the identified hazards can be mitigated to a level where the risk of human life and damage to property are reduced to an acceptable and reasonable level, in a manner which has a minimum effect on the natural environment and the built environment and will not violate applicable federal, state or local statutes, ordinances or regulations, then the proposed mitigations and land use may be approved by the City. As part of an approval, the City Geologist shall provide an advisory letter that assesses the value and appropriateness of any proposed mitigation techniques. 4. Areas determined to be undevelopable shall be designated as permanent open space within the subdivision or site plan, and shall be designated through an acceptable permanent sensitive land preservation instrument as set forth in MKZ 18.51.130. D. The City Geologist on behalf of the City may impose other requirements as are necessary to overcome any geologic hazards and to ensure that the purposes of this chapter are met. These requirements may include, but are not limited to: 1. Additional or more detailed studies to understand or quantify the hazard or determine whether mitigation measures recommended in the report are adequate; 2. Specific mitigation requirements; establishment of buildable and/or non- buildable areas; limitations on slope grading; and/or revegetation; 3. Installation of monitoring equipment and seasonal monitoring of surface and subsurface geologic conditions, including groundwater levels; 4. Areas determined to contain geologic hazards, that are hazardous to life or property shall not be approved for development. 5. Other requirements, including but not limited to time schedules for completion of the mitigation and phasing of development. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 21 6. Grading plans, shall be prepared, signed and stamped by a licensed professional engineer and shall meet the requirements as set forth in the Engineering Requirements Checklist 18.51.120 On Site Professional and Final Inspection A. Professional Inspection. The City requires that a qualified professional be on site, at the cost of the developer, during certain phases of construction, particularly during grading phases, to verify that development is occurring in a manner compliant with the approved Geotech report. Verification includes, but is not limited to, the construction of retaining walls, density testing as required by the design engineer, and the construction of any approved mitigation(s). For any real property with respect to which development has proceeded on the basis of a geologic or geotechnical report which has been accepted by the City, no final inspection shall be completed until the geotechnical engineer or engineering geologist who signed and approved the report certifies and delivers to the City, in writing, that the completed improvements and structures conform to the descriptions, designs, and requirements contained in said report. B. Design Engineer Verification. The design engineer shall inspect the construction of all slopes or cut and fill areas, provide all documentation of compaction / densities and inspection reports within 14 days of each major completed task. Including but not limited to drain system/canyon drain, benching, soil nails and material with optimal moisture content used with proctor. The design engineer must certify in writing that all slope are built per the approved design and shall submit that certification to Millcreek Engineering. 18.51.130 Acceptable Permanent Sensitive Land Preservation Instruments A. If sensitive lands are not retained in private ownership, such areas shall be preserved through either a conservation easement, , a dedication as accessible public open space to the City with a conservation easement, a deed restriction with an HOA or common area maintenance commitment, or other means that assure permanent preservation and are accepted by the City. Such areas shall include public access points, where trails are included in the preserved sensitive lands. If one of the above techniques is not utilized other preservation techniques may be negotiated as part of a development agreement with the City Council. Undevelopable sensitive lands held privately shall include a recorded deed restriction easily found in a Title report that states portions of the lot are undevelopable. Such portions shall be clearly identified via mapping or a legal description. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 22 B. Sensitive Lands Preservation Incentives through Density Transfers within the Development. To promote the preservation and avoidance of identified sensitive lands, density transfers/clustering may occur within a development proposal. The density shall reflect only the additional units that could have been built on the preserved areas. Any of the sensitive lands defined in this ordinance may qualify for density transfers except for unbuildable areas above a 30% slope, avalanche/landslide/mud/debris flow corridors, fault lines, and areas delineated by ACOE as wetlands. Where densities are transferred within a project, the resulting new development shall receive flexibility in setbacks, and lot sizes. Such transfers shall be implemented and established through negotiation with the City Council in a development agreement, after a recommendation by the Planning Commission. C. Developments that include Homeowner’s Associations. Such developments shall include restrictive covenants with mitigation techniques for the continued maintenance, preservation, and enhancement of Sensitive Lands and their associated open spaces. 18.51.140 Other Considerations A. Buried springs and streams. Existing development may have buried springs and/or piped streams, which could have potential cultural and historical value. If new development or significant redevelopment of the site’s structures, defined as over 50 percent (50%) of the building is being proposed, modified or replaced, efforts to re- establish an open stream or utilize the spring as a water feature, shall be considered in the design process. Buried/capped wells and pipes may be impractical to reestablish the natural feature. B. Low Impact Development (LID) Storm Water Erosion and Pollution prevention techniques. Techniques are required as set forth in Millcreek Stormwater Management plan, as adopted and amended from time to time by the City Council . Any retention basins shall be free form, following the natural landforms. If such forms do not exist, the basin shall be shaped to emulate a naturally formed depression, including the sloped edges shall prevent erosion and be landscaped with native vegetation. Natural drainage channels shall be preserved. C. Trees. Trees, including Heritage trees shall be addressed as required by the Landscaping Ordinance. Oak and maple groves over 5000 square feet in sized, shall be identified and avoided in the site design. Significant trees shall be replaced with locally hardy, low water demand 2” caliper trees. For each significant tree removed two replacement trees are required. Measures to protect existing trees shall be taken during construction. Unauthorized tree removal shall result in fines and a stoppage of City processing until the removals are replaced or a value, established by a working nursery or arborist (selected by the City) is estimated and a commensurate amount paid to the City. ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 23 D. Recorded Deed Restrictions. Where sensitive lands are identified and represent a hazard, a deed restriction shall be recorded, defining the sensitive land hazard, and locating it on the property for future owners to be aware. Existing Properties and Lots of record. The owner of an existing property or a lot of record legally created prior to the adoption of this chapter is not entitled to a building permit, unless that building permit fully complies with all requirements of this chapter, and all other applicable requirements. These requirements protect the public health, safety, and welfare of the community, and may prevent development on sensitive lands, especially steep slopes, areas with hazardous soils, and other sensitive lands features. 18.51.150 Warning And Disclaimer A. The Sensitive Lands ordinance codified in this chapter and Sensitive Lands hazard maps represent only those hazardous areas known to the City, and should not be construed to include all possible potential hazard areas. This ordinance and associated maps may be amended as new information becomes available pursuant to procedures set forth in this ordinance. The provisions of this chapter do not in any way assure or imply that areas outside its boundaries will be free from the possible adverse effects of geologic hazards. This chapter shall not create liability on the part of the City, any officer or employee thereof for any damages from geologic hazards that result from reliance on this chapter. Definitions "Limits of disturbance" means area(s) in which construction and development activity are to be contained, including development and construction of the principal building, accessory structures, recreation areas, utilities, services, driveways, septic tank drain fields and related system requirements, storm drainage, and other similar services or improvements. “Ridgeline” means an area of topographical change, running parallel to a slope and having at least a 20’ rise over a 60’ wide area on one side of the ridge and extending for at least 300’. "Stream, Ephemeral" means those channels, swales, gullies, or low areas that do not have flow year-round or are not shown on United States Geological Services (U.S.G.S.) topographic maps as perennial streams. These are generally channels that are tributary to perennial streams, other ephemeral streams, terminal low areas, ponds, or lakes. They are typically dry except during periods of snowmelt runoff or intense rainfall. (Contrast with “Stream, Perennial.”) "Stream, Perennial" means those streams, excluding ephemeral streams, or ditches and canals constructed for irrigation and drainage purposes, which flow year-round during years of normal rainfall, and that are identified on the appropriate United States Geological Services (U.S.G.S.) topographic maps as perennial streams. (Contrast with “Stream, Ephemeral.”) ---PAGE BREAK--- Millcreek Together Code Update I Chapter 18.51 Sensitive Lands Overlay (SLO) Zone I v5 24 "Stream corridor" The corridor defined by a perennial stream’s ordinary high water mark. "Wildland Urban Interface” means the line, area or zone where structures or other human development (including critical infrastructure that, if destroyed, would result in hardship to communities) meet or intermingle with undeveloped wildland or vegetative fuel.