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Painted Hills FEIS - MAY 2023 Painted Hills Development Final Environmental Impact Statement (FEIS) Spokane Valley, Washington May 2023 This page intentionally left blank. Painted Hills Residential Development | Spokane Valley, Washington Page i Final Environmental Impact Statement TABLE OF CONTENTS SECTION 1. INTRODUCTION ..................................................................................................................... 1 1.1 INTRODUCTION .................................................................................................................................... 1 1.2 BACKGROUND ...................................................................................................................................... 2 1.3 PUBLIC SCOPING PROCESS ................................................................................................................... 3 1.4 SCOPE OF THE FINAL ENVIRONMENTAL IMPACT STATEMENT ............................................................ 3 1.5 FINAL ENVIRONMENTAL IMPACT STATEMENT PUBLIC COMMENT ..................................................... 4 SECTION 2. FINAL ENVIRONMENTAL IMPACT STATEMENT ...................................................................... 6 FACT SHEET ................................................................................................................................................ 6 2.1 PURPOSE AND NEED ............................................................................................................................ 8 2.2 LAND DEVELOPMENT ALTERNATIVES .................................................................................................. 9 2.2.1 Alternatives Analysis in this FEIS .................................................................................................... 9 2.2.1.1 Alternative 1: No Action ...................................................................................................... 9 2.2.1.2 Alternative 2a: Planned Residential Development—High Infiltration ................................. 9 2.2.1.3 Alternative 2b: Planned Residential Development-- Low Infiltration ................................ 10 2.2.2 Alternatives Eliminated from Consideration....................................................................... 10 2.2.2.1 Low Impact Subdivision Alternative ......................................................................... 10 2.2.2.2 Standard Subdivision Alternative ............................................................................ 13 2.2.3 Mitigation Measures .................................................................................................................... 18 2.2.4 Permits and Approvals Required for Implementation ................................................................. 18 2.2.5 Relationship Between FEMA and Local Review Processes .......................................................... 19 SECTION 3. AFFECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES ................................... 22 3.1 NATURAL ENVIRONMENT (GROUND AND SURFACE WATER) ............................................................ 22 3.1.1 Affected Environment .................................................................................................................. 22 3.1.1.1 Existing Hydrologic Conditions .......................................................................................... 22 3.1.2 Environmental Consequences ..................................................................................................... 28 3.1.2.1 Alternative 1 – No Action .................................................................................................. 28 3.1.2.2 Alternative 2a – Planned Residential Development—High Infiltration ............................. 28 3.1.2.3 Alternative 2b – Planned Residential Development—Low Infiltration .............................. 29 3.1.3 Mitigation Measures .................................................................................................................... 30 3.1.3.1 Alternative 1 ...................................................................................................................... 30 3.1.3.2 Alternative 2a .................................................................................................................... 30 3.1.3.3 Alternative 2 ...................................................................................................................... 30 Painted Hills Residential Development | Spokane Valley, Washington Page ii Final Environmental Impact Statement 3.1.4 Cumulative Effects ....................................................................................................................... 30 3.2 BUILT ENVIRONMENT (LAND USE AND FLOOD HAZARD AREAS) ....................................................... 31 3.2.1 Affected Environment .................................................................................................................. 31 3.2.2 Environmental Consequences ..................................................................................................... 34 3.2.2.1 Alternative 1 – No Action .................................................................................................. 34 3.2.2.2 Alternative 2a – Planned Residential Development-High Infiltration ............................... 35 3.2.2.3 Alternative 2b – Planned Residential Development-Low Infiltration ...................... 47 3.2.3 Mitigation Measures .................................................................................................................... 48 3.2.4 Indirect Effects ............................................................................................................................. 50 3.2.5 Cumulative Effects ....................................................................................................................... 50 3.3 TRANSPORTATION .............................................................................................................................. 51 3.3.1 Affected Environment .................................................................................................................. 52 3.3.1.1 Study Area ......................................................................................................................... 52 3.3.1.2 Existing Conditions............................................................................................................. 54 3.3.2 Environmental Consequences ..................................................................................................... 56 3.3.2.1 Alternative 1 – No Action .................................................................................................. 56 3.3.2.2 Alternative 2a – Planned Residential Development High Infiltration Rate........................ 58 3.3.2.3 Alternative 2b – Planned Residential Development—Low Infiltration Scenario ............... 64 3.3.3 Mitigation Measures .................................................................................................................... 66 3.3.4 Cumulative Effects ....................................................................................................................... 68 3.4 ENVIRONMENTAL ELEMENTS NOT ANALYZED IN DETAIL .................................................................. 69 3.4.1 Air Quality .................................................................................................................................... 69 3.4.1.1 Affected Environment .............................................................................................. 69 3.4.1.2 Environmental Consequences .................................................................................. 70 3.4.1.3 Mitigation Measures ................................................................................................ 71 3.4.1.4 Cumulative Effects ................................................................................................... 72 3.4.2 Aesthetics .................................................................................................................................... 72 3.4.2.1 Affected Environment .............................................................................................. 72 3.4.2.2 Environmental Consequences ........................................................................................... 73 3.4.2.3 Mitigation Measures ................................................................................................ 73 3.4.2.2 Environmental Consequences .................................................................................. 77 3.4.2.3 Mitigation Measures ................................................................................................ 77 3.4.2.4 Cumulative Effects ................................................................................................... 78 3.4.3 Biological Resources .................................................................................................................... 78 Painted Hills Residential Development | Spokane Valley, Washington Page iii Final Environmental Impact Statement 3.4.3.1 Affected Environment .............................................................................................. 78 3.4.3.2 Environmental Consequences .................................................................................. 83 3.4.3.3 Mitigation Measures ................................................................................................ 84 3.4.3.4 Cumulative Effects ................................................................................................... 84 3.4.4 Environmental Health .................................................................................................................. 84 3.4.4.1 Affected Environment .............................................................................................. 84 3.4.4.2 Environmental Consequences .................................................................................. 85 3.4.4.3 Mitigation Measures ................................................................................................ 85 3.4.4.4 Cumulative Effects ................................................................................................... 85 3.4.5 Geology ........................................................................................................................................ 85 3.4.5.1 Affected Environment........................................................................................................ 85 3.4.5.2 Environmental Consequences .................................................................................. 86 3.4.5.3 Mitigation Measures ................................................................................................ 86 3.4.5.4 Cumulative Effects ................................................................................................... 87 3.4.6 Historic, Cultural, and Archaeological Resources ........................................................................ 87 3.4.6.1 Affected Environment .............................................................................................. 87 3.4.6.2 Environmental Consequences .................................................................................. 87 3.4.6.3 Mitigation Measures ................................................................................................ 88 3.4.6.4 Cumulative Effects ................................................................................................... 89 3.4.7 Noise ............................................................................................................................................ 89 3.4.7.1 Affected Environment .............................................................................................. 89 3.4.7.2 Environmental Consequences .................................................................................. 89 3.4.7.3 Mitigation Measures ................................................................................................ 90 3.4.7.4 Cumulative Effects ................................................................................................... 90 3.4.8 Public Services ............................................................................................................................. 90 3.4.8.1 Affected Environment .............................................................................................. 90 3.4.8.2 Environmental Consequences .................................................................................. 92 3.4.8.3 Mitigation Measures ................................................................................................ 98 3.4.8.4 Cumulative Effects ................................................................................................... 98 3.4.9 Recreation .................................................................................................................................... 98 3.4.9.1 Affected Environment .............................................................................................. 98 3.4.9.2 Environmental Consequences ................................................................................ 102 3.4.9.3 Mitigation Measures .............................................................................................. 102 3.4.9.4 Cumulative Effects ................................................................................................. 102 Painted Hills Residential Development | Spokane Valley, Washington Page iv Final Environmental Impact Statement ACRONYMS AND ABBREVIATIONS....................................................................................................... 104 LITERATURE CITED ............................................................................................................................... 106 APPENDIX A: SEPA CHECKLIST ..................................................................................................................I APPENDIX B: PUBLIC COMMENT INDEX ...................................................................................................II APPENDIX C: IMPACT COMPARISON TABLE – ALTERNATIVE 2A V. STANDARD SUBDIVISION ................ IV APPENDIX D: STANDARD SUBDIVISION ALTERNATIVE ENVIRONMENTAL REVIEW ................................ VI APPENDIX E: FLOOD CONVEYANCE SYSTEM ELEMENT FAILURE RISK AND IMPACT SUMMARY ........... VIII APPENDIX F: TRAFFIC IMPACT ANALYSIS ................................................................................................ X APPENDIX G: TRUCK HAUL MEMORANDUM ........................................................................................ XII APPENDIX H: BIOLOGICAL EVALUATION(PAINTED HILLS PRD & OFF-SITE) ........................................... XIV APPENDIX I: CULTURAL RESOURCES SURVEY – PAINTED HILL .............................................................. XVI APPENDIX J: CULTURAL RESOURCES SURVEY – GUSTIN PIPE OFF-SITE .............................................. XVIII APPENDIX K: FLOOD CONVEYANCE SYSTEM DIAGRAM ........................................................................ XX APPENDIX L: CERTIFICATE OF TRANSPORTATION CONCURRENCY ...................................................... XXII APPENDIX M: TECHNICAL MEMORANDUM REPORT – CHESTER CREEK ............................................. XXIV APPENDIX N: 100-YEAR FLOODPLAIN: CURRENT VS. HEADWORKS FAILURE SCENARIO ..................... XXVI APPENDIX O: DRAFT OPERATIONS AND MAINTENANCE MANUAL .................................................. XXVIII APPENDIX P: REVISED FLOOD CONTROL NARRATIVE .......................................................................... XXX Painted Hills Residential Development | Spokane Valley, Washington Page v Final Environmental Impact Statement TABLES Table 1-1: Painted Hills Site Tax Lots ...................................................................................................... 1 Table 2-1. Project Purpose and Need v. Low Impact Subdivision ......................................................... 11 Table 3-1: Transportation Impact Analysis Land Use Types (TIA Table 5) ............................................ 51 Table 3-2: Level of Service Descriptions ............................................................................................... 52 Table 3-3: Year 2015 Existing Intersections Levels of Service (Table 2 of TIA) ..................................... 55 Table 3-4: Background Projects and Vested AM & PM Trips Table 4 of TIA) ........................................ 56 Table 3-5: 2025 Levels of Service, without the Project, with the Background Projects (Table 7 of TIA) ................................................................................................................ 57 Table 3-6: Estimated Trip Generation – Alternative 2a ........................................................................ 58 Table 3-7: Year 2025 Levels of Service, with the Project, with the Background Projects (Table 19 of the TIA) ........................................................................................................ 59 Table 3-8: Alternative 2A and 2B ADT Comparison – PM Peak Hour Trips ........................................... 64 Table 3-9: Background Projects and Vested AM & PM Trips ................................................................ 69 Table 3-10: Alternative 2A. Estimated Potential Annual Levy Funds Generated at Buildout ............... 94 Table 3-11: Alternative 2b. Estimated Potential Annual Levy Funds Generated at Buildout ............... 97 FIGURES Figure 1-1: Vicinity Map .......................................................................................................................... 2 Figure 2-1 Low Impact Subdivision ....................................................................................................... 12 Figure 2-2 Standard Subdivision ........................................................................................................... 14 Figure 2-3 Alternative 2a Site Plan including Gustin Ditch Improvements ........................................... 15 Figure 2-4: Alternative 2b Site Plan including Gustin Ditch Improvements .......................................... 16 Figure 2-5: Alternatives 2a and 2b Comparison .................................................................................... 17 Figure 3-1: Chester Creek 1997 Flood Event – Aerial Photo ................................................................. 23 Figure 3-2: Flooding West of Chester Main Channel (Viewing Eastward on Thorpe) ........................... 23 Figure 3-3: Flooding East of Chester Main Channel (Viewing Westward on Thorpe) ........................... 24 Figure 3-4: Current Drainage Features ................................................................................................. 26 Figure 3-5: Spokane Valley - Rathdrum Prairie Sole-Source Aquifer .................................................... 27 Figure 3-6: Existing FEMA Mapped Floodplain Areas ........................................................................... 33 Figure 3-7: Proposed Drainage Features .............................................................................................. 37 Figure 3-8: Alternatives 2a and 2b – Existing & Future Floodplain Areas ............................................. 38 Painted Hills Residential Development | Spokane Valley, Washington Page vi Final Environmental Impact Statement Figure 3-9: Painted Hills Flood Management System Element Locations ............................................. 41 Figure 3-10: Study Area Intersections ................................................................................................... 74 Figure 3-11: View of the Site from S. Madison Road ............................................................................ 75 Figure 3-12: View of the Site from E. Thorpe Road............................................................................... 75 Figure 3-13: View of the Site from S. Dishman-Mica Road ................................................................... 76 Figure 3-14: Former Clubhouse and Associated Parking ...................................................................... 76 Figure 3-15: Priority Habitat & Species ................................................................................................. 82 Figure 3-16: Service District Boundaries ............................................................................................. 100 Figure 3-17: Public Recreation Opportunities ..................................................................................... 101 APPENDICES Appendix A ....................................................................................................................................... SEPA Checklist Appendix B .......................................................................................................................... Public Comment Index Appendix C ................................................... Impact Comparison Table – Alternative 2a v. Standard Subdivision Appendix D .................................................................... Standard Subdivision Alternative Environmental Review Appendix E ............................................... Flood Conveyance System Element Failure Risk and Impact Summary Appendix F .......................................................................................................................... Traffic Impact Analysis Appendix G ............................................................................................................. Truck Haul Plan Memorandum Appendix H .......................................................................... Biological Evaluation (Painted Hills PRD and Off-Site) Appendix I ...................................................................................... Cultural Resources Survey (Painted Hills PRD) Appendix J .................................................................................. Cultural Resources Survey (Gustin Pipe Off-Site) Appendix K .....................................................................................................Flood Conveyance System Diagram Appendix L ........................................................................................... Certificate of Transportation Concurrency Appendix M .............................................................................. Technical Memorandum Report – Chester Creek Appendix N ............................................................100-Year Floodplain: Current vs. Headworks Failure Scenario Appendix O ..................................................................................... DRAFT Operations and Maintenance Manual Appendix P .......................................................................................................... Revised Flood Control Narrative Painted Hills Residential Development | Spokane Valley, Washington Page vii Final Environmental Impact Statement This page intentionally left blank. Painted Hills Residential Development | Spokane Valley, Washington Page 1 Final Environmental Impact Statement SECTION 1. INTRODUCTION 1.1 INTRODUCTION The subject site of this Final Environmental Impact Statement (FEIS) is an approximately 99.3-acre former golf course located in the City of Spokane Valley (City), referred to herein as the “Painted Hills site.” The Painted Hills site can be generally described as within the southeast (SE) quadrant of Section 33, Township 25 North. Range 44 East, Willamette Meridian. (See Figure 1-1: Vicinity Map). The site is primarily vacant. Although no longer in operation and no longer maintained, the former golf course use is evident by the presence of former fairways, greens, and other golf course features. The former golf course driving range is now in operation as a commercial driving range that is expected to continue to operate until the City’s issuance of an approval on the Planned Residential Development (PRD) request. Table 1-1 identifies the tax lots that compose the subject site, along with the ownership and current zoning designation of the site. The golf course use terminated in 2013 prior to the site being purchased by the current owner. Table 1-1: Painted Hills Site Tax Lots Tax Lot Owner Zoning Size (Acres) 45334.0109 Black Realty, Inc. R3 0.87 45334.0108 Black Realty, Inc. R3 0.87 45334.0113 Black Realty, Inc. R3 0.27 45334.0110 Black Realty, Inc. R3 0.87 44041.9144 Black Realty, Inc. R3 8.24 45334.9135 Black Realty, Inc. R3 1.68 45334.0114 Black Realty, Inc. R3 0.60 45336.9191 Black Realty, Inc. R3 85.07 45334.0106 Black Realty, Inc. R3 0.87 TOTAL 99.34 In addition to improvements occurring on the tax lots identified in Table 1-1, the action alternatives considered in this EIS include improvements to a stormwater pond on tax lot 45343.9052, approximately 1,900 feet east of the northeast corner of the Painted Hills site and to an existing approximately 1,350-foot-long ditch located on tax lots 45344.9155 and 45344.9154. This off-site stormwater pond is referred to as “the triangle pond” due to its triangular shape. The ditch, referred to as the “Gustin Ditch” due to the historical ownership of the underlying parcel, conveys stormwater to the southeast corner of the pond. The project applicant is under contract to purchase the triangle pond property and will complete the purchase prior to construction. Access to the triangle pond will occur via East 40th Avenue, a public local access road. Easement rights to pipe and maintain the Gustin Ditch will be obtained prior to initiation of construction. Painted Hills Residential Development | Spokane Valley, Washington Page 2 Final Environmental Impact Statement 1.2 BACKGROUND On July 24, 2015, NAI Black, herein identified as the “applicant” submitted a PRD application request to the City to construct a new mixed-use development that would include single family residential estate lots, standard single-family lots, cottage or townhome units, multi-family units, commercial development, and open space on the 99.3-acre former golf course site. In its review of the application, the City determined that probable significant adverse impacts could result from stormwater and floodwater improvements and traffic generated by the project. The terms stormwater and floodwater are used to describe separate and distinct sources of water on the project site. The Federal Emergency Management Association (FEMA) defines a flood as complete or partial inundation of two or more acres of normally dry land or of two or more properties from overflow of inland or tidal waters, unusual and rapid accumulation, or runoff of surface waters from any source. The term floodwater in the FEIS refers to those waters originating from rapid accumulation or runoff of surface waters from any source, e.g., a storm event (25-year, 100-year, and 500-year storm event) and snowmelt. By comparison, stormwater is defined by the Environmental Protection Agency (EPA) as rainwater or melted snow that runs off streets, lawns, and other sites, due to impervious surfaces such as pavement and roofs which prevent precipitation from naturally soaking into the ground. Stormwater in the FEIS refers to surface water runoff originating from impervious surfaces within the Painted Hills PRD. Figure 1-1: Vicinity Map Painted Hills Residential Development | Spokane Valley, Washington Page 3 Final Environmental Impact Statement 1.3 PUBLIC SCOPING PROCESS On September 8, 2017, the City issued a determination of significance (DS) for the proposed action that identified that an EIS should be prepared to evaluate the effects of the project on the natural environment (ground and surface water), the built environment and transportation. Following the September 8, 2017, issuance of the DS, a public scoping period was held including a public scoping meeting on September 25, 2017. From this public scoping comment period, 251 comments were received. In the weeks following this meeting, it was determined that certain project modifications could be made that would improve the design of floodwater improvements and simplify the long-term management responsibility for these improvements. Between the Fall of 2017 and July 2018, the applicant refined the design of the PRD alternative (Alternative 2a in this FEIS document) and, on August 20, 2018, submitted a supplemental State Environmental Policy Act (SEPA) Checklist that described the refined project design and included additional environmental documentation regarding the environmental effects of the applicant’s proposed action (See Appendix A). After review of this supplemental SEPA Checklist, the City issued a revised DS, dated October 26, 2018. 124 public comments were received in response to the reissued DS. 1.4 SCOPE OF THE FINAL ENVIRONMENTAL IMPACT STATEMENT The DS stated that an EIS should be prepared for the revised project that addresses the natural environment (ground and surface water); built environment (land use, including relationship to land use plans regarding flood hazard areas); and transportation, including the importation of fill. The DS further stated that the alternatives to be analyzed in the EIS should include a “No Action” alternative, the applicant’s Preferred Alternative and an “Alternative 2 Alternative Configuration.” The DS stated that this Alternative 2 Alternative Configuration was intended to evaluate “other reasonable alternatives for achieving the proposal’s objective on the same site according to the existing development regulations.” As discussed further in this document, alternative configurations were considered for the project consistent with the DS. These alternative configurations included a “low impact alternative” that substantially avoided development within designated 100-year floodplain areas and a “standard subdivision” alternative that provided standard single family detached lots throughout the site. After considering these alternatives, it was determined that the low-impact alternative did not sufficiently meet the Purpose and Need for the project which, as a private development, includes the need for a reasonable economic return to the owner and project investors. Further, it was determined that the standard subdivision proposal resulted in marginally increased environmental effects and therefore did not sufficiently meet the criteria for a reasonable alternative consistent with WAC 197-11-440(5)(b). Consequently, these alternatives were eliminated from further consideration. A summary of these alternatives that were considered and subsequently eliminated from further consideration is included in Section 2.2 of the EIS. This document is focused on evaluating the environmental impacts of two alternatives for the Painted Hills site as noted below: Alternative 1 (No Action Alternative): This alternative assumes no development of the site. Alternative 2 (PRD): This alternative represents development of the site through a PRD as permitted under section 19.50 of the Spokane Valley Municipal Code (SVMC) and includes significant floodwater management improvements including a gallery of infiltration dry wells. Because a final design infiltration rate within the planned ponds/drywells will not be known until a drywell is installed per City Standard Plans and tested, the precise design infiltration rate cannot be determined at this time. As a consequence, the applicant has developed one action PRD alternative with two variations (Alternative 2a and Alternative 2b) for analysis in this document. Alternative 2a assumes high infiltration rates Painted Hills Residential Development | Spokane Valley, Washington Page 4 Final Environmental Impact Statement and therefore a smaller (1.4-acre) floodwater management facility and Alternative 2b assumes lower infiltration rates and therefore a larger (9.3-acre) floodwater management facility. After receiving additional public comments in response to the second DS issuance, the City determined that additional environmental elements would be addressed in the document but to a lesser degree than the primary environmental elements listed in the DS. Those additional elements are included in this document and include:  Air Quality  Aesthetics  Biological Resources  Environmental Health  Geology  Historic, Cultural and Archaeological Resources  Noise  Public Services  Recreation 1.5 DRAFT ENVIRONMENTAL IMPACT STATEMENT PUBLIC COMMENT AND EIS UPDATES On July 16, 2021, the City issued notice of the Draft Environmental Impact Statement (DEIS) for a 45-day public comment period. Following the close of the public comment period, the City held a virtual public meeting on September 8, 2021, to obtain further comment and to inform the public of the project and DEIS review status. In total, there were 218 written comments received on the DEIS during the public comment period. These comments are compiled in a matrix format included as Appendix B. The matrix in Appendix B includes direct responses from the EIS author and identifies DEIS sections that have been updated, where applicable. Upon review of comments received on the DEIS during the public comment process, it was determined that revisions to the EIS document were appropriate to provide the following general clarifications: Section 1.1, Introduction:  Updates have been made to clarify the ownership of the Triangle Pond and access to it. Section 3.1 , Natural Environment (Ground and Surface Water)  Updates have been made to clarify the relationship between the triangle pond infiltration and private wells adjacent to the triangle pond and the Painted Hills PRD site.  Updates have been made to clarify the relationship between on-site development and Chester Creek base flows. Section 3.2, Built Environment (Land Use and Flood Hazard Areas):  Updates have been made to clarify long-term maintenance requirements and safety redundancies for on and off-site flood control components, including the triangle pond. Painted Hills Residential Development | Spokane Valley, Washington Page 5 Final Environmental Impact Statement  Updates have been made to clarify the sources of floodwater and implications of a flood conveyance failure event, primarily at the system headworks.  Updates have been made to clarify the vegetative conditions within the upstream Chester Creek Basin for context regarding the improbability of an obstruction at the trash racks.  Updates have been made to include calculations for estimated future replacement costs of the flood conveyance system.  Updates have been made to identify the design standards for stormwater management elements.  Updates have been made to address Chester Creek overflow impacts on hydrologic and hydraulic modeling. Section 3.3, Transportation:  Updates have been made to discuss analysis of cut-through traffic through the Midilome neighborhood.  Updates have been made to discuss construction-related and trip-generated traffic effects on pedestrian and cyclist safety.  Updates have been made to clarify access on Dishman-Mica Road for construction-related traffic and elaborate on the expected number of trips per day associated with fill activities under both alternatives  Updates have been made to add new mitigation measures, including those provided by the city that discuss updating the traffic study relative to procedural reviews.  Updates have been made to add mitigation measures, including a Rectangular Rapid Flashing Beacon (RRFB) crosswalk at the intersection of East 40th Avenue and South Pines/South Madison Road, installation of a two-way, left-turn on Dishman-Mica Road at the site entry, and the installation of northbound right-turn lane on Dishman-Mica Road at the site entry. Section 3.4, Environmental Elements Not Analyzed in Detail:  Updates have been made discussing the fish-bearing status of Chester Creek and implications on site development.  Updates have been made to discuss archaeological and biological surveys at the Triangle Pond property.  Updates have been made to clarify the means by which schools manage and maintain capacities in conjunction with growth.  Updates have been made to clarify the means by which utility providers manage and maintain capacities in conjunction with growth.  Updates have been made to clarify emergency evacuation routes during a wildfire. Please refer to Appendix B for a detailed list of comprehensive responses to public comments and the location of all revisions. SECTION 2. FINAL ENVIRONMENTAL IMPACT STATEMENT FACT SHEET Proposal/Title: Painted Hills Development Final Environmental Impact Statement Description of Proposal: Planned development of the former Painted Hills golf course site to include a mix of residential and commercial uses integrated with open space areas. Description of Alternatives: Two primary alternatives are analyzed: the No Action Alternative (Alternative 1) and the Planned Residential Development (PRD) Alternative, which includes two variations, a “High Infiltration Alternative” (Alternative 2a) and a “Low Infiltration Alternative” (Alternative 2b). Location: 99.3 acres located at Section 33, Township 25 North, Range 44 East, West Meridian (on-site) 14.86 acres located at Section 34,Township 25 North, Range 44 East, West Meridian (off-site) Project Proponent: Black Realty Inc. Tentative Date of Implementation: Summer 2023 Name and Address of Lead Agency and Contact: City of Spokane Valley, Contact: Lori Barlow Responsible Official: Chaz Bates, Planning Manager Required Local Approvals: Preliminary Plat/ Planned Residential Development (PRD) Transportation Concurrency Certificate Street Plan Approval, Right-of-Way (ROW) Permits (COSV) Sanitary Sewer Plan Approval (Spokane County) Water Plan Approval (Water District 3) Building Permits (COSV) Landscape Plans (COSV) Grading and Erosion Control Permit (COSV) Spokane Regional Clean Air Agency (SRCAA) & Washington Department of Ecology (WDOE) Air Quality Permits (as applicable) Painted Hills Residential Development | Spokane Valley, Washington Final Environmental Impact Statement Page 6 City Floodplain Development Permit & Land Disturbance Permit (COSV) Floodplain Development Permit & Land Disturbance Permit (Spokane County) Project Manager and Principal Contributors to Final EIS: City of Spokane Valley Contact: Lori Barlow, Senior Planner 11707 E. Sprague Avenue, Suite 106 Spokane Valley, WA 99206 (EIS Review and Approval) WEST Consultants, Inc. Contact: Ken Puhn, P.E. 2601 25th St SE #450 Salem, OR 97302 (Floodplain Impact Analysis) DOWL Contact: Read Stapleton, AICP 720 SW Washington Street; Suite 750 Portland, OR 97205 (EIS Preparation) Biology, Soil, & Water, Inc. Contact: Larry Dawes 3102 N. Girard Road Spokane Valley, WA 99212-1529 (Biological Resources) Whipple Consulting Engineers, Inc. Contact: Ben Goodmansen 21 S. Pines Spokane Valley, 99206 (Civil Engineering and Stormwater Hydrology) Date of Issuance of Final EIS: June 5, 2023 Location of Copies of Final EIS for Public Review: Notice of Availability and copies of the FEIS have been distributed to agencies, organizations, and individuals who commented or requested to receive notice. The FEIS is available for download and review on the city’s website: https://www.spokanevalley.org/paintedhillsfeis Hard Copies of the FEIS are also available for public review at the following location: Spokane Valley City Hall 10210 E Sprague Avenue Spokane Valley, WA 99206 Copies of the FEIS may be purchased for the cost of reproduction. Painted Hills Residential Development | Spokane Valley, Washington Final Environmental Impact Statement Page 7 Painted Hills Residential Development | Spokane Valley, Washington Page 8 Final Environmental Impact Statement 2.1 PURPOSE AND NEED The purpose of the proposed action is to relieve the under-supply of housing in the Spokane Valley area by implementing a mixed-use residential development that furthers the goals and policies of the City of Spokane Valley Comprehensive Plan and satisfies the owner’s investment return requirement. According to Rob Higgins Executive Vice President of the Spokane Association of Realtors, Spokane County has limited housing inventory. The current inventory as of November 2020 is 74 new construction single family residential properties, and 337 existing single-family residential properties, for a total of 411 properties currently on the market. This represents a supply of approximately one week of housing inventory. The City has long recognized the Painted Hills site as being subject to more intense development. The site is currently designated as Single Family Residential and zoned as R-3. The R-3 zone is the City’s “urban residential” category which allows a potential density of up to 6 units per acre and “provides flexibility and promotes reinvestment in existing single-family neighborhoods.” (SVMC 19.20.015(C). The City zoned the property R-3 to enable maximum residential buildout of the site while recognizing the potential limiting environmental factors. Consistent with the planning goals of the Growth Management Act (GMA) codified in Revised Code of Washington (RCW) 36.70A.020, development should be encouraged “in urban areas where adequate public facilities and services exist or can be provided in an efficient manner.” Local plans and policies implement the GMA and limit new urban development to areas within the Urban Growth Area (UGA) and constrain the supply of available land. Further, Spokane County is subject to explicit limitations on UGA expansions as stipulated in Section 10 of a 2016 Settlement Agreement with parties who appealed the county’s 2013 UGA expansion. Given the limited ability of Spokane County to expand UGAs and the fact that the proposed development site is one of the largest contiguously owned buildable tracts of residential land in Spokane Valley, the Painted Hills site represents a unique opportunity to provide needed housing supply. Because the UGA constrains potential development in other areas in the region and other environmental or infrastructure limiting factors may restrict developable sites within the UGA, there are few, if any, tracts within Spokane County that allow development to occur on the same scale as the Painted Hills site. The proposed action also satisfies the reasonable investment backed expectations of the applicant. The applicant acquired the property for the purpose of redevelopment after a long-tenured golf facility became financially unfeasible. The use of the planned residential overlay allows for the applicant to develop the site in the manner preferred by the City while providing for floodwater facilities that enhance the open space and recreational value of the project. The expense of the facilities required to develop the project are financially significant and can only be offset by the development of the proposed action at the scale provided for by the applicant. The contemplated land uses, and density of the proposed action are not subject to review because they fit within the adopted development regulations of the City [See RCW 36.70B.030(3)]. This FEIS has been prepared in accordance with the Washington SEPA (RCW 43.21C). This FEIS is not a decision document. The primary purpose of this FEIS is to disclose the potential environmental impacts of implementing the proposed action. Painted Hills Residential Development | Spokane Valley, Washington Page 9 Final Environmental Impact Statement 2.2 LAND DEVELOPMENT ALTERNATIVES This section describes and compares alternatives evaluated in this FEIS and alternatives that were considered for evaluation but ultimately eliminated. This FEIS analyzes a no-action alternative (Alternative 1) and one action PRD alternative with two variations (Alternatives 2a and 2b). Additional alternatives were initially considered for evaluation in this FEIS. These included a “Low Impact Standard Subdivision” alternative that avoided development within most of the 100-year floodplain areas within the site and a “Standard Residential Subdivision Alternative” with similar stormwater and floodwater management features as the PRD alternative. These alternatives and the reasons for their exclusion from more detailed analysis in this FEIS are discussed further below. This document includes a detailed discussion of impacts to environmental elements identified as a potential concern in the DS. The primary environmental categories analyzed in detail in this EIS include natural environment (ground and surface water); built environment (land use, including relationship to land use plans regarding flood hazard areas); and transportation. Secondary environmental elements that were not addressed in the DS are addressed in brief summaries in this document. These environmental elements include air quality, aesthetics, biological resources, environmental health, geology, historic, cultural, and archaeological resources, noise, public services, and recreation. 2.2.1 Alternatives Analysis in this FEIS The alternatives analyzed in this FEIS are described further below. 2.2.1.1 Alternative 1: No Action The No Action Alternative provides a baseline for comparing the effects of the action alternatives. The No Action Alternative assumes that no on-site or off-site improvements occur in conjunction with or as a result of a residential project on the Painted Hills site. 2.2.1.2 Alternative 2a: Planned Residential Development—High Infiltration Alternative 2a (see Figure 2-3) involves the redevelopment of the Painted Hills site into a PRD within the City. The project will consist of approximately 42 estate single family residential lots, 206 standard single-family residential lots, 52 cottage-style single family residential lots, 228 multi-family residential units, 52 mixed use multi-family residential units integrated with approximately 13,400 square feet of retail/commercial use, 9,000 square feet of future stand-alone retail commercial use and the preservation of the club house and associated parking as a commercial area. Additionally, the site will include greenspace totaling approximately 30 acres including a 10-acre park and wildlife travel corridor. A network of asphalt trails will also be provided. The Painted Hills project will include the construction of streets and sidewalks to access the lots, as well as water, sanitary sewer, and dry utility facilities to serve each lot. Off-site and on-site floodwater management infrastructure improvements will be made that will result in the removal of approximately 48 acres of the site from the FEMA one percent annual-chance-floodplain (100-year floodplain). Floodwater management improvements occurring on the site and on the site frontages will include the replacement of existing culverts under Thorpe Road with a box culvert structure, installation of a concrete lined channel to a pipe system leading to treatment and infiltration facilities; and routing and disposal of flood and seasonal flows that cross Madison Road into a new Painted Hills floodwater management system. Conceptual conveyance of floodwater is illustrated in Appendix K. In addition to on-site improvements, Alternative 2a includes replacing the Gustin Ditch northeast of the Painted Hills site with a 36-inch pipe. Additionally, the proposal includes triangle pond improvements that include Painted Hills Residential Development | Spokane Valley, Washington Page 10 Final Environmental Impact Statement deepening the pond’s detention basin and installing 18 drywells in the pond bottom to increase the pond’s capacity to infiltrate flows received from the Gustin Ditch under frozen ground conditions. These off-site improvements will eliminate 100-year and 500-year floodwater inflows onto the Painted Hills site from the east as modeled in the current FEMA floodplain insurance study. Further details regarding the design and impacts of the floodwater management improvements under the two PRD variations are provided in the individual environmental element sections of this EIS. Street frontage improvements along Dishman-Mica Road, Thorpe Road, and Madison Road will include curb, gutter, landscape planter strips and/or swales, and sidewalks and/or trails. It is expected that, upon the completion of site grading activities, a FEMA Letter of Map Revision (LOMR) will be completed that would also result in the removal of approximately 44 acres of off-site properties from the FEMA 100-year floodplain. Upon completion of the project, approximately 92 acres will be removed from the FEMA 100-year floodplain on the project site and on off-site properties. 2.2.1.3 Alternative 2b: Planned Residential Development-- Low Infiltration Alternative 2b (see Figure 2-4), like Alternative 2a, involves the redevelopment of the Painted Hills site golf course site as a PRD within the City. The primary difference between the two alternatives is that Alternative 2b significantly increases the size of the floodwater infiltration pond and drywell infiltration gallery at the northern limits of the site. The infiltration pond is larger in Alternative 2b to address recent (January 2020) infiltration testing that indicates slower infiltration might occur on the site when compared to infiltration testing conducted on the site in May of 2016. Therefore, the two variations of the PRD alternative (Alternatives 2a and 2b) provide an analysis of two floodwater storage scenarios on the site (a high infiltration rate scenario and a lower infiltration rate scenario) and the minor PRD refinements that occur on the site around the floodwater storage area. The Alternative 2b development plan consists of 48 estate single family residential lots, 224 standard single- family residential lots, 273 multi-family residential units, 52 mixed use multi-family residential units integrated with approximately 13,400 square feet of retail/commercial use, 9,000 square feet of future stand-alone retail commercial use and the preservation of the club house and associated parking as a commercial area. Additionally, the site will include open space areas totaling approximately 30 acres including a 10-acre park and wildlife travel corridor. The same off-site floodwater infrastructure improvements completed under Alternative 2a would also be constructed under Alternative 2b. Further details regarding the design and impacts of Alternative 2b are provided in the individual environmental element sections of this EIS. See Figure 2-5 for a comparison between Alternative 2a and Alternative 2b. 2.2.2 Alternatives Eliminated from Consideration Through the process of considering alternatives in addition to the applicant’s preferred alternative—PRD Alternatives 2a and 2b—the development team reviewed two other possible alternatives for evaluation in the FEIS. These alternatives are discussed further below. 2.2.2.1 Low Impact Subdivision Alternative In addition to the preferred alternative, the applicant considered a residential development on the site that would avoid development within nearly all mapped 100-year floodplain areas. This alternative is reflected in Figure 2-1. This Low Impact Subdivision Alternative would allow the development of approximately 205 small single family residential “cottage” lots with widths varying between 20 and 40 feet. After review, the applicant determined the alternative failed to meet the project purpose and need as required under WAC 197-11- 440(5)(b). Table 2-1 provides an analysis of the Low Impact Subdivision Alternative relative to the project purpose and need. Painted Hills Residential Development | Spokane Valley, Washington Page 11 Final Environmental Impact Statement Table 2-1. Project Purpose and Need v. Low Impact Subdivision Project Purpose and Need Elements Low Impact Subdivision Improve regional undersupply of housing and fulfill the City’s plan for residential development at urban densities of 6 units per acre. 205 residential units over the 99.3 acres site fails to realize the development potential on the site as designated by the City and as needed to fulfill a regional undersupply of housing. Development of the Low Impact Subdivision alternative would only achieve a gross density of approximately two units per acre, far below the plan-designated capacity of six units per acre. Therefore, this alternative fails to adequately address the housing need within Spokane Valley and the greater Spokane metropolitan area. Satisfy investment backed expectations of the applicant. The proposed project is a private development funded by private investment and, as such, requires that the developer can attain financial returns necessary to satisfy investor obligations and to fund necessary public infrastructure. These infrastructure investments include water, sanitary sewer, road, and stormwater improvements, including improvements to Thorpe Road water passages that regularly flood. The financial return gained from the development of 205 cottage lots is insufficient to satisfy these investment-backed expectations for the project. Painted Hills Residential Development | Spokane Valley, Washington Page 12 Final Environmental Impact Statement Figure 2-1 Low Impact Subdivision Painted Hills Residential Development | Spokane Valley, Washington Page 13 Final Environmental Impact Statement 2.2.2.2 Standard Subdivision Alternative The applicant also considered the development of the site as a standard subdivision. This alternative is illustrated on Figure 2-2 and would involve the same general improvements and fill requirements associated with Alternative 2a. Further, because it would be developed under the City’s standard subdivision requirements and not through a PRD, this alternative would not require setting aside 30 percent of the site for open space. The applicant conducted a thorough analysis of this alternative and concluded this alternative resulted in marginally greater environmental impacts when compared to Alternatives 2a and 2b. Consequently, the alternative failed to meet the standard under WAC 197-11-440(5)(b) which requires that reasonable alternatives should have a “lower environmental cost or decreased level of environmental degradation.” This alternative was therefore eliminated from further analysis in the FEIS. A summary comparison of the environmental impacts associated with the Standard Subdivision alternative is included in Appendix C and an unabridged version of the environmental analysis conducted for the standard subdivision is included as Appendix D. Painted Hills Residential Development | Spokane Valley, Washington Page 14 Final Environmental Impact Statement Figure 2-2 Standard Subdivision Painted Hills Residential Development | Spokane Valley, Washington Page 15 Final Environmental Impact Statement Figure 2-3 Alternative 2a Site Plan including Gustin Ditch Improvements Painted Hills Residential Development | Spokane Valley, Washington Page 16 Final Environmental Impact Statement Figure 2-4: Alternative 2b Site Plan including Gustin Ditch Improvements Painted Hills Residential Development | Spokane Valley, Washington Page 17 Final Environmental Impact Statement Figure 2-5: Alternatives 2a and 2b Comparison Painted Hills Residential Development | Spokane Valley, Washington Page 18 Final Environmental Impact Statement 2.2.3 Mitigation Measures Mitigation is intended to avoid or to minimize the potential environmental impacts related to the action alternatives that are proposed. The definition of mitigation under SEPA, that will be used for the purposes of this analysis can be found in WAC 197-11-768 and as noted below: “Mitigation” means: (1) Avoiding the impact altogether by not taking a certain action or parts of an action; (2) Minimizing impacts by limiting the degree or magnitude of the action and its implementation, by using appropriate technology, or by taking affirmative steps to avoid or reduce impacts; (3) Rectifying the impact by repairing, rehabilitating, or restoring the affected environment; (4) Reducing or eliminating the impact over time by preservation and maintenance operations during the life of the action; (5) Compensating for the impact by replacing, enhancing, or providing substitute resources or environments; and/or (6) Monitoring the impact and taking appropriate corrective measures. Mitigation measures are addressed in the environmental elements of Section 3. Affected Environment and Environmental Consequences. 2.2.4 Permits and Approvals Required for Implementation The following local, state, and federal permits will be required to implement the development under Alternative 2. Local Permits/Authorizations  Preliminary Plat/ PRD  Transportation Concurrency Certificate (Complete dated 2-23-17)  Street Plan Approval, ROW Permits (COSV)  Sanitary Sewer Plan Approval (Spokane County)  Water Plan Approval (Water District 3)  Building Permits (COSV)  Landscape Plans (COSV)  Grading and Erosion Control Permit (COSV)  Spokane Regional Clean Air Agency (SRCAA) & Washington Department of Ecology (WDOE) Air Quality Permits (as applicable)  City Floodplain Development Permit & Land Disturbance Permit (COSV)  Floodplain Development Permit & Land Disturbance Permit (Spokane County) State Permits/Authorizations  Construction Stormwater General Permit (CSWGP) Federal Permits/Authorizations  FEMA Conditional Letter of Map Revision (CLOMR) and Letter of Map Revision (LOMR) Painted Hills Residential Development | Spokane Valley, Washington Page 19 Final Environmental Impact Statement 2.2.5 Relationship Between FEMA and Local Review Processes In its review and consideration of this FEIS, the City has requested that the applicant provide a summary of the relationship between FEMA’s review process and the City’s review process and how the array of possible outcomes from FEMA’s review might affect the applicant’s project and the local review process. This section offers a brief discussion of these issues. First, because the installation of dry wells for infiltration testing requires SEPA review, the applicant must complete the EIS review process prior to installing the dry wells and conducting infiltration testing. Because the dry well testing is necessary to confirm the final flood conveyance system design, the applicant expects FEMA to complete its CLOMR review after the City completes the EIS review process and makes a final local decision on the PRD request. The applicant would then install the dry wells, and make any design refinements, if necessary. Final processing of the CLOMR requires the City and County floodplain administrators to sign the Community Acknowledgment Forms (CAF). The applicant anticipates that these local agencies will sign the CAFs after the installation of the dry wells and after the applicant’s design team makes any final system design refinements, following the EIS hearing. Through coordination between the project applicant, the City, and Spokane County, FEMA has agreed to conduct a preliminary review of the CLOMR request in advance of receiving the CAFs. FEMA review of the CLOMR application is in process and FEMA has provided initial comments to the applicant on May 24, 2022, and a second round of comments to the applicant on December 21, 2022. These comments request relatively minor revisions such as expanded responses and revisions to application materials. No modification of the flood conveyance system design is required as a result of these comments; however, the technical review process is not yet complete, and FEMA may provide additional comments that need to be addressed. Because it is expected that the CLOMR review and the City construction document review will be occurring at the same time, the applicant expects that any system design revisions requested/required by FEMA to ensure approval of the CLOMR will be integrated with revisions to the construction document package as necessary before the City issues final approval of the construction documents. If the CLOMR review results in changes to the PRD, such changes would require review and consideration by the City per the provisions of SVMC 19.50.070(B), which stipulate the process for review of changes to approved PRDs. Per SVMC 19.50.070.B(1), if such revisions are determined to affect “precise dimensions or siting of buildings, but which do not affect the basic character or arrangement of buildings approved in neither the final plan, the density of the development, nor the open space requirements” they can be approved by the city manager in conjunction with the building permit and without further land use review. SVMC 19.50.070.B(1) further stipulates that “dimensional adjustments shall not vary more than 10 percent from the original” in order for the changes to be allowed without a revision to the approved PRD. If FEMA’s CLOMR review requires modifications to the approved PRD in a manner that exceeds the thresholds of SVMC 19.50.070.B(1), then such changes are considered a “major adjustment.” In such an instance, the project revisions will require submittal of the adjustment for review by City staff and for final review and approval by the City hearing examiner. If this occurs, it is anticipated that the PRD revision process would proceed concurrent with FEMA’s review of the revised design. The process for addressing SEPA compliance for project changes after the issuance of a FEIS is addressed in WAC 197-11, Sections 600-640. The array of SEPA review possibilities for project changes could include: (A) no review necessary consistent with WAC 197-11-600(2); (B) an EIS addendum is prepared that finds that the revisions do not substantially change the analysis of significant impacts and alternatives per WAC 197-11- 600(4(c); or (C) a supplemental EIS is prepared documenting that substantial changes are proposed that will likely have significant adverse environmental impacts or new information is provided indicating a proposal's Painted Hills Residential Development | Spokane Valley, Washington Page 20 Final Environmental Impact Statement probable significant adverse environmental impacts per WAC 197-11-600(4)(d). Because the analysis provided in this FEIS contemplates and addresses the range of environmental effects that can be expected to result from the range of infiltration test results, it is anticipated that the SEPA review process necessary for any design refinements needed to address FEMA’s review would be conducted consistent with (A) above and WAC 197- 11-600(2). The FEMA map revision process concludes with a final LOMR. The LOMR process is completed upon the final installation of fill and flood conveyance improvements per the specifications of the CLOMR and after as-built conditions are provided to FEMA to certify that improvements have been installed consistent with the CLOMR request. Painted Hills Residential Development | Spokane Valley, Washington Page 21 Final Environmental Impact Statement This page intentionally left blank. Painted Hills Residential Development | Spokane Valley, Washington Page 22 Final Environmental Impact Statement SECTION 3. AFFECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES 3.1 NATURAL ENVIRONMENT (GROUND AND SURFACE WATER) The following section provides a description of the existing conditions of ground and surface waters within the project site and the potential for the project alternatives to affect ground and surface water quality. The ecological features of Chester Creek including habitat functions of the creek and the associated riparian buffer are described in Section 3.4.3.1 Biological Resources. 3.1.1 Affected Environment 3.1.1.1 Existing Hydrologic Conditions The Painted Hills site is in the Chester Creek basin in the southeastern portion of Water Resource Inventory Area (WRIA) 57. Chester Creek originates south of the project site in an area dominated by agricultural lands and rural home sites. The creek flows generally northward, crosses through the southwest corner of the Painted Hills site through a concrete box culvert and terminates in an infiltration basin located approximately four miles south of the Spokane River and northwest of the project site adjacent to Dishman-Mica Road (see Figure 3-4). Peak flooding in the Chester Creek basin typically occurs in winter, unlike the Spokane River system where flooding typically occurs in early spring. Warm winds and rain can melt snow rapidly, leading to low velocity short-duration runoff flooding during winter storms (Michael Baker Inc. 1990). During flood events, Chester Creek has been noted to overtop its banks south of the Painted Hills site and floodwater collects in topographically low areas east of the main channel (See Figure 3-1, Chester Creek 1997 Flood Event - Aerial Photo). Floodwater from south of Thorpe Road eventually reach the Painted Hills site through three 15-inch culverts located under Thorpe Road approximately 500 feet east of where the main channel of Chester Creek crosses Thorpe Road. Under higher flow conditions, water also flows over the road and onto the Painted Hills site at this same location as shown in Figures 3-1, 3-2, and 3-3. Painted Hills Residential Development | Spokane Valley, Washington Page 23 Final Environmental Impact Statement Figure 3-1: Chester Creek 1997 Flood Event – Aerial Photo1 Figure 3-2: Flooding West of Chester Creek Main Channel (Viewing Eastward on Thorpe)2 1 Photo source: WEST Consultants, Inc.; Originally provided by Spokane County. Photo date and flood event type unknown. 2 Photo taken by WCE on March 14, 2017. Painted Hills Residential Development | Spokane Valley, Washington Page 24 Final Environmental Impact Statement Figure 3-3: Flooding East of Chester Main Channel (Viewing Westward on Thorpe)3 Spokane Rathdrum Prairie Aquifer A portion of the Spokane Valley-Rathdrum Prairie Sole Source Aquifer, which is the primary water source for over 700,000 people in the Spokane region, underlies the Painted Hills site. The aquifer is a large underground formation consisting of gravels, cobbles, and boulders and is reported to store 10 trillion gallons of water (MacInnis et al 2009). The aquifer extends from western Idaho to the eastern area of Washington State. This underground formation extends south from near the Bonner County-Kootenai County line in Idaho west of Lake Pend Oreille. From there, it extends south toward Coeur d’Alene Lake and then west into Washington through the Spokane River Valley as shown in Figure 3-5. The aquifer follows the valley and terminates near the confluence of the Spokane and Little Spokane Rivers west of the City of Spokane. Water is contributed to the aquifer by adjacent lakes, streams, the Spokane River, and precipitation. This highly permeable area of deposits is covered in many locations by a relatively thin topsoil layer and is therefore susceptible to pollution. The Spokane Valley-Rathdrum Prairie Aquifer was designated a Sole Source Aquifer in 1978. On the Painted Hills site, the aquifer is overlain by a relatively slow-draining topsoil layer. Groundwater depths vary on the site. Multiple geotechnical borings have been conducted on the site by Inland Pacific Engineering Company (IPEC). Field investigations and borings have been taken in different locations and at different times of the year. Geotechnical borings were taken at multiple times between April and October 2014 at locations immediately adjacent to Chester Creek along the site. These borings revealed groundwater depths ranging from 7.5 to 18 feet, with shallower depths closer to Thorpe Road (IPEC, Feb 12, 2015 / Revised Aug 29, 2016). Borings taken up to a depth of 25 feet near the Chester Creek crossing of Dishman-Mica Road failed to reach the water table. Geotechnical borings taken in January 2015 reveal groundwater depths ranging from 11 to 47 3 Photo taken by WCE on February 17, 2017. Painted Hills Residential Development | Spokane Valley, Washington Page 25 Final Environmental Impact Statement feet throughout the south-central portion of the site (IPEC, July 23, 2016). Additional borings taken in March 2016 at the north end near the planned floodwater infiltration facility found depths of 71 feet and deeper. Therefore, the composite of investigations completed for the site indicate a moderately deep to very deep groundwater table profile across the site, with the deepest locations at the north end of the site near the location of the planned floodwater infiltration facility. It should be noted that multiple infiltration tests have been conducted on the Painted Hills site. These include both full-scale drywell tests and bore hole infiltration tests to determine the potential infiltration rates expected from the proposed drywell facilities. IPEC completed a full-scale drywell test on the Painted Hills site on May 6, 2016, and the results from this analysis were documented in an August 21, 2017 report. This test determined that each drywell should be assumed to have a design “outflow” rate of 1.05 cubic feet per second (cfs) after applying a safety factor of safety of 1.1. The interface surface is between the native soil and the drywell rock placed around each drywell. This calculation results in a design infiltration rate of 1.8 x 10-3 cfs/square foot. A full-scale drywell test, as conducted with the IPEC study, is considered the best method to determine the actual operation or outflow rate that a drywell would have. The installation method involves first excavating the native soil, then lining the area with a geofabric material, covering all exposed native material, installing drywell barrels and then backfilling the voids with drain rock. Once the drain rock is placed, geofabric is installed over the top of the drain rock up to the cone of the drywell and then backfilled. This method ensures the highest infiltration rates into the native soil material and best replicates the function of the proposed drywells. In a 2019 review of the Whipple Consulting Engineers (WCE) infiltration design for the preferred alternative, the City’s third-party engineering consultant, Stantec, recommended additional infiltration testing, within the site area where the proposed infiltration pond will be located. This was due to the fact that the full-scale drywell that was tested was 230 feet from the location of the drywell gallery in Alternative 2a to avoid impacts within the 100-year floodplain. In response to this request, the applicant hired Budinger & Associates, Inc. to perform additional infiltration testing within the location of the gravel/drywell gallery. Because the future drywell gallery is within the 100-year floodplain, the City determined that the installation of a drywell in this location would exceed minimum SEPA review thresholds. Therefore, a full-scale drywell test was not conducted in this location, as was done with the May 2016 IPEC test, and instead Budinger & Associates conducted infiltration testing using bore holes. The bore hole testing used an 8-inch diameter steel casing drilled down to a depth of 60 feet. For the infiltration test the bottom 30 feet of a bore hole was filled with pea gravel. The casing pipe was then lifted 30 feet exposing the pea gravel to the native soil. It has been noted by the engineers that this method introduces a layer of fine silty material against the casing pipe. With the removal of the casing pipe the layer of silty material remains between the interface of the native soil and the pea gravel and can inhibit infiltration. Once established the bore holes were filled with water and a constant hydraulic head was maintained. The measured water provided an outflow rate for the bore hole. An average of the observed rates from three bore hole tests resulted in an infiltration rate of 4.6296 x 10-6 cfs/square foot, which is less than the IPEC full scale drywell test. This result is documented in the June 1, 2020 Budinger report. While the results of the two infiltration tests vary considerably, WCE believes that the true design infiltration rate lies somewhere in between. As a result, the applicant has prepared two alternatives under the preferred development. Alternative 2a has been designed with floodwater management facilities assuming high infiltration rates per the May 2016 IPEC study and Alternative 2b was developed to reflect the much slower infiltration rates of the Budinger & Associates, Inc. study. These two variations of Alternative 2 are discussed in greater detail throughout this document. Painted Hills Residential Development | Spokane Valley, Washington Page 26 Final Environmental Impact Statement Figure 3-4: Current Drainage Features Painted Hills Residential Development | Spokane Valley, Washington Page 27 Final Environmental Impact Statement Figure 3-5: Spokane Valley - Rathdrum Prairie Sole-Source Aquifer Painted Hills Residential Development | Spokane Valley, Washington Page 28 Final Environmental Impact Statement 3.1.2 Environmental Consequences 3.1.2.1 Alternative 1 – No Action Under Alternative 1, there will be no physical improvements on-site or off-site that would affect floodwater flows or change ground conditions. Floodwaters that currently reach the Painted Hills site will continue to reach the site and will remain on site until they are able to infiltrate to the aquifer. Under Alternative 1, there would be no significant impact to the channel of Chester Creek. Floodwaters would continue to reach the Painted Hills site as they currently do and would remain onsite until they are able to infiltrate naturally to the underlying Spokane Valley-Rathdrum Prairie Aquifer. Because no change to ground conditions would occur, Alternative 1 would have no significant impact on the Spokane Rathdrum Prairie Aquifer. Under Alternative 1, there would be no significant impact on residential wells adjacent the Painted Hills site. The underlying Spokane Valley-Rathdrum Prairie Aquifer would continue, as it currently does, to supply the water for these wells. 3.1.2.2 Alternative 2a – Planned Residential Development—High Infiltration Under Alternative 2a, the widening of Thorpe Road to meet city road standards would require a 15-foot widening of the Chester Creek bridge. Additionally, a new box culvert would be installed at Thorpe Road, in the location where three 15-inch pipes currently convey floodwaters onto the Painted Hills site from the property to the south. Floodwater that enters the project site under this alternative would be collected in a series of pipes and swales and would infiltrate into the Spokane Valley-Rathdrum Prairie aquifer via an engineered infiltration basin. Although annual inflow volumes have not been determined, peak two-year storm event inflows from the Unnamed Tributary and the Golf Course Overflow Reach to the 68 drywells within the two facilities are estimated to be less than 13 cfs. These inflows are derived from mostly rural subbasins with low contaminant loads relative to developed areas with significant impervious surfaces from roofs, streets, and parking lots. For comparison, the highly developed 2.81 sq mi drainage area to the north contains 1,059 drywells that drain directly to the aquifer. This drainage area is estimated to have a peak two-year event inflow to the 1,059 drywells of approximately 167 cfs, which is 13 times greater than the estimated peak inflow from the two FEMA identified flooding sources. Therefore, floodwaters will continue to infiltrate on the site under typical conditions and no appreciable change in volumes of water that reach the aquifer via the Painted Hills site are anticipated to occur under Alternative 2a. This conclusion is supported by findings in a technical memorandum prepared by WEST Consultants March 12, 2008, and included with this FEIS as Appendix M. Under Alternative 2a, no significant impacts to the channel of Chester Creek from the widening of Thorpe Road are anticipated. If it is confirmed that the existing web girder bridge cannot be widened by adding a box culvert, Thorpe Road Bridge (SPOKV-4421) will be redesigned to satisfy the design elements and requirements outlined in the WSDOT Bridge Design Manual (LRFD) M23-50.20, dated September 2020. In this case, a new load rating for the bridge will be established. Under Alternative 2a, there would be no significant impact to the volume of the Spokane Valley-Rathdrum Prairie aquifer. Water that currently recharges the aquifer would continue to recharge the aquifer through permeable areas on-site including the infiltration pond installed in the northeast corner of the Painted Hills site and therefore no significant impacts to the existing groundwater levels are anticipated and as supported through findings in WEST’s technical memorandum (Appendix M). Groundwater mounding beneath infiltration structures such as the infiltration pond proposed under Alterative 2a can cause localized flooding in situations where there is a subsurface limiting layer at or just below the bottom of the structure. Based on the results of infiltration tests described in Section 3.1.1.1, soils underlying the Painted Hills site are alluvial soils with fine particles on top of coarse sands. These coarse sands are Painted Hills Residential Development | Spokane Valley, Washington Page 29 Final Environmental Impact Statement reported to extend 70 feet below the ground surface. Based on the presence of this deep deposit of permeable material, groundwater mounding beneath the proposed infiltration system is not anticipated. Under Alternative 2a, there would be no significant impact to residential wells. All existing residential wells are located at least 100 feet from the drywells proposed for the Triangle Pond. WAC 173-160-171 provides minimum setback distances ranging from 5 feet to 100 feet for wells from most potential contamination sources. The proposed drywells and infiltration basin would not generate contamination that could affect the quality of water in the residential wells and under the WAC the setback distance would be sufficient to protect the residential wells even if the drywells or infiltration basin were considered sources of contaminants. Under Alternative 2a and 2b, there would be no significant impact to water quality or quantity in the channel of Chester Creek from stormwater due to the fact that stormwater from all impervious surfaces associated with new development will be treated in accordance with the Spokane Regional Stormwater Manual (SRSM) and directed to the stormwater management system, which is separated from the floodwater management system and is not connected to Chester Creek. The proposed flood control components are designed to convey and infiltrate flood water during a 100-year flood event and would not restrict or draw down existing flows in Chester Creek. Stormwater runoff from impervious surfaces within the Painted Hills PRD site would be typical of the development types—commercial, multi-family and single family residential—occurring with the project. Stormwater from residential lots is anticipated to infiltrate on the lots, or flow from driveways to the public rights of way, where stormwater will be directed to roadside swales for treatment. Similarly, in the future multi-family and commercial areas, stormwater will be treated, detained, and infiltrated consistent with the Spokane Regional Stormwater Manual (SRSM). The two 48-inch pipes would end at a vertical headwall where the floodwater would be released onto a concrete pad and flow across a level spreader into a sloped, 269 cfs capacity biofiltration swale. Suspended solids in the floodwater would be filtered out by tall grasses planted in the biofiltration swale. At the end of the biofiltration swale, the water would enter a settling pond where additional suspended sediments would precipitate to the floor of the pond. Water would be retained in the settling pond until the pond depth exceeds 1 foot, at which point the water would flow through two 48-inch pipes into either a 1.4 or 9.3-acre infiltration pond that would be 2 feet below the elevation of the rock weir. The biofiltration swale, settling pond, and infiltration pond will be designed to meet standards of the SRSM and Ecology’s Stormwater Management Manual for Eastern Washington (SWMMEW). 3.1.2.3 Alternative 2b – Planned Residential Development—Low Infiltration Under Alternative 2b, as with Alternative 2a, the widening of Thorpe Road to meet city road standards would require a 15-foot widening of the Chester Creek bridge. Under Alternative 2b, stormwater quality and quantity impacts would be the same as those described for Alternative 2a. As described for Alternative 2a, under Alternative 2b, there would be no significant impacts to water quality and water quantity in the channel of Chester Creek from the widening of Thorpe Road; and there would be no significant impact to the Spokane Valley-Rathdrum Prairie aquifer. Water that currently recharges the aquifer would continue to recharge through the permeable floor of the infiltration basin proposed in the northeast corner of the Painted Hills site. As with Alternative 2a, it is not anticipated that Alternative 2b would significantly impact residential wells as WAC 173-160-171 provides minimum setback distances ranging from 5 feet to 100 feet for wells from most potential contamination sources. The proposed drywells and infiltration basin do not pose a significant risk to Painted Hills Residential Development | Spokane Valley, Washington Page 30 Final Environmental Impact Statement the quality of water in the Spokane Valley-Rathdrum Aquifer and, by association, the nearby residential wells due to the greater than 100-foot setback between the Painted Hills PRD and the nearest well. 3.1.3 Mitigation Measures 3.1.3.1 Alternative 1 There are no significant impacts with Alternative 1, therefore no mitigation measures would be required. 3.1.3.2 Alternative 2a Mitigation for Alternative 2a would consist of floodwater management methods that include the installation of grassed percolation areas, evaporation ponds, drywells, and gravel galleries depending upon soil types at the locations of the proposed facilities. Stormwater management methods from the Eastern Washington Low Impact Design (LID) manual or LID ponds may be used to minimize the extent of runoff from new on-site impervious surfaces created with the onsite development. 3.1.3.3 Alternative 2 Mitigation for Alternative 2b consists of the same floodwater management methods as those described for Alternative 2a above, except that under Alternative 2b, the permeable infiltration basin will be larger. 3.1.4 Cumulative Effects Because on-site and regional development would be required to employ floodwater quality and quantity management measures consistent with the SRSM, no cumulative effects are anticipated. Painted Hills Residential Development | Spokane Valley, Washington Page 31 Final Environmental Impact Statement 3.2 BUILT ENVIRONMENT (LAND USE AND FLOOD HAZARD AREAS) 3.2.1 Affected Environment Land Uses and Zoning The current land use of the Painted Hills site is a non-operating golf course. The former club house has been repurposed as a commercial restaurant. On February 5, 2021, the City approved a Conditional Use Permit (CUP) request (CUP-2020-0004) that allows for the re-utilization of the former Painted Hills golf course driving range as a commercial driving range use on the site. The driving range will not require any new improvements and will occupy an approximately 7.38-acre location within the Painted Hills site. The driving range will be located northeast of the existing restaurant building and customers of the driving range facility will park in the existing parking lot. The no action alternative assumes that the driving range will continue as a land use on the property. SEPA review for the driving range facility occurred in conjunction with the City’s review of CUP-2020-0004 and the City’s SEPA documentation for the driving range is incorporated by reference. Pursuant to Condition 7 of the CUP approval, the driving range approval will expire upon the City’s issuance of an approval on the PRD request filed under SUB-2015-0001/PRD-2015-0001.The current land uses adjacent to the Painted Hills site include a mix of dense single-family residential development on former agricultural land, remaining undeveloped small tracts of agricultural land, and forested land with varying densities of residential development. Land uses surrounding the project site include, north of the property line into the City, dense residential development. A church and residential development border the Painted Hills site at the northwest (NW) corner. A Central Valley School district campus including University High school, Chester Elementary School and Horizon Middle School is located northeast (NE) of the site. From the east property line (S. Madison Road) hay fields and pasture extend 250 to 500 feet toward the toe of the surrounding forested slopes. Low density rural residential development extends east up the forested hillsides. Commercial and single-family residential development extends south from Thorpe Road except for the Chester Creek drainage and associated flood plain areas which are mainly forested and small tract agriculture. Undeveloped forested hillsides extend about 1,200 feet east to the densely developed Ponderosa neighborhood. A mixture of commercial and residential land uses extends NW along Dishman-Mica Road. The current zoning classification of the Painted Hills site is R-3, Single Family Residential, and the Comprehensive Plan designation is Low Density Residential (LDR). Sources of Flooding Floodwater has been known to enter the Painted Hills site from two separate locations: 1) from a split flow path originating from the main channel of Chester Creek south of the Painted Hills site (known as the Golf Course Overflow Reach), and 2) from the hills to the east of Madison Road which borders the eastern boundary of the Painted Hills site. The effective FEMA Flood Insurance Study (FIS), as shown on Figure 3-6, indicates that floodwater could enter the Painted Hills site from a third location during the 1 percent annual-chance-flood event (100-year flood). Based on the FIS, floodwater originating from an unnamed tributary to Chester Creek near State Route (SR) 27 could potentially reach the Painted Hills site from the northeast. Additional details regarding these three sources of floodwater and how they flow onto the Painted Hills PRD site are provided below. Floodwater enters the Painted Hills site from the south when the main channel of Chester Creek overflows its banks approximately 3,000 feet upstream (south) of Thorpe Road. This floodwater flows north along a topographically low area east of the main channel of the creek and reaches the Painted Hills site through three 15-inch culverts located under Thorpe Road approximately 500 feet east of where the main channel of Chester Painted Hills Residential Development | Spokane Valley, Washington Page 32 Final Environmental Impact Statement Creek crosses Thorpe Road. Under higher flow conditions water also flows over the road and onto the project site at this same location. The floodwater originating from south of the Painted Hills site does not rejoin the mainstem of Chester Creek due to topography and the presence of a small on-site levee system located along the right bank of the main channel, as well as the Dishman-Mica Road embankment located north of the levee. Instead, the floodwater remains on the Painted Hills site until it infiltrates (WEST 2016). Runoff also reaches the project site from the east. Water from the hillside above and east of Madison Road flows to a flat area adjacent to the east side of Madison Road and is conveyed onto the project site through four 15-inch culverts (a fifth culvert exists but does not convey water onto the site because the outlet is buried), (Personal Communication with Ken Puhn, WEST Consultants 2018). The area east of Madison Road is included in the mapped FEMA 100-year floodplain as shown on Figure 3-6. There are no natural outlets for floodwater once it reaches the Painted Hills site. Once the site is inundated, water remains until it can infiltrate to the aquifer below. Depending upon the amount of floodwater present, the southern portion of the Painted Hills site can remain flooded for up to 40 days. (Biology, Soil & Water 2019) An unnamed tributary to Chester Creek near Highway 27 east of the Painted Hills site currently conveys stormwater flows towards the site via a 36-inch culvert and this culvert empties into a perched ditch that flows west across the Gustin property (Parcel Number 45344.9108). The floodwater flows through the ditch and into triangle pond located northeast of E 40th Avenue (Parcel Number 45343.9052). The existing ditch has been maintained over the years by the property owner to ensure that any floodwater that comes out of the culvert under Highway 27 will be conveyed to the existing triangle detention pond. This off-site area is included in the mapped FEMA 100-year floodplain. The south embankment of the perched ditch is considered by FEMA to be a levee that is not certified to contain the 100-year flood; therefore, the FEMA FIS also includes mapping that represents a failure of the south bank during which floodwaters flow south to a lower elevation and then flow west to the Painted Hills site, bypassing the triangle pond. Painted Hills Residential Development | Spokane Valley, Washington Page 33 Final Environmental Impact Statement Figure 3-6: Existing FEMA Mapped Floodplain Areas Painted Hills Residential Development | Spokane Valley, Washington Page 34 Final Environmental Impact Statement FEMA Floodplain Designation FEMA’s 100-year floodplain designation has both regulatory and financial implications for development on the Painted Hills site. From a regulatory perspective, any development within the 100-year floodplain in the City triggers review under SVMC Section 21.30 (Floodplain Regulations). For properties within unincorporated Spokane County, floodplain development triggers review under Spokane County Code (SCC) Section 3.20 (Flood Damage Protection). These regulations stipulate measures that must be taken in order to change site grades within a floodplain, including compensatory measures to mitigate potential off-site flooding if fill is proposed within a floodplain. The regulations also include floodproofing measures for new structures in the floodplain and other development standards. Adoption of these local standards is necessary for a community to participate in FEMA’s National Flood Insurance Program (NFIP) which enables a community to have access to flood insurance. If a property can successfully be removed from FEMA’s mapped 100-year floodplain through FEMA’s LOMR process, it can be relieved of both the regulatory burden of compliance with the local floodplain ordinance and also of the financial burden of the requirement to obtain flood insurance, which is a requirement of any Federal Housing Authority (FHA)-insured mortgage. Due to the lack of an outlet and the potential for floodwaters to enter the Painted Hills site from two separate locations, the Painted Hills site is designated by FEMA as a compensatory storage area in the 2010 Flood Insurance Study (FEMA 2010). Additionally, much of the Painted Hills site is included in the mapped FEMA 100- year floodplain. See Figure 3-6, Existing Mapped FEMA Floodplain Areas. The overall purpose of the “compensatory storage” designation is to ensure that development activities do not cause an adverse impact on flood elevations within the designated compensatory storage area, or upstream or downstream of the development. The designation is intended to ensure that there is no increase in the volume of water reaching the downstream sites due to reduced infiltration capacity or due to fill within the area that could cause an increase to flood elevations on neighboring properties. Under the compensatory storage area designation, any loss of flood storage capacity on the Painted Hills site due to placement of fill must be mitigated with an equivalent compensatory volume of storage or through a reduction in flows such that the net condition causes no adverse impact to the base flood or floodway elevations within the storage area. In addition, loss of infiltration capacity due to placement of fill or impervious surfaces must be mitigated to ensure that any decrease in infiltration capacity will cause no adverse impact to the base flood or floodway elevations within or upstream or downstream of the storage area. In summary, development activities within a compensatory storage area must be compensated or mitigated to ensure no adverse impacts to flood levels. 3.2.2 Environmental Consequences 3.2.2.1 Alternative 1 – No Action Under Alternative 1, there would be no modifications to the existing system of culverts and ditches that convey floodwater onto the Painted Hills site. There would be no change in the mapping of the 100-year floodplain on- site or off-site and the Painted Hills site would maintain its FEMA compensatory storage area designation. Under this alternative, when Chester Creek overtops its banks south of the Painted Hills site, floodwaters would potentially inundate the property south of Thorpe Road and flow under, and potentially over Thorpe Road to reach the Painted Hills site. Floodwater that reach the site from the south would reside on the Painted Hills site and on the property to the south, and naturally infiltrate to the Spokane Valley-Rathdrum Prairie aquifer. No significant impacts to land use or the extent of the 100-year floodplain are anticipated under Alternative 1 because no alterations would be implemented on or adjacent to the Painted Hills site. Therefore, all properties that are currently subject to the floodplain regulations and the NFIP would remain as currently mapped by FEMA. Painted Hills Residential Development | Spokane Valley, Washington Page 35 Final Environmental Impact Statement 3.2.2.2 Alternative 2a – Planned Residential Development-High Infiltration Sources of Floodwater Under Alternative 2a, the Chester Creek floodwaters will continue to reach the site and will be received and managed through a series of conveyance and recharge improvements. The potential impacts of floodwater from the unnamed tributary to Chester Creek NE of the Painted Hills site will be eliminated due to placement of the existing Gustin Ditch into a pipe that connects directly to the triangle pond detention basin where floodwaters will infiltrate. Floodplain Map Modifications and Floodwater Management Improvements Under Alternative 2a, the applicant proposes to address the FEMA requirements associated with the compensatory storage area designation through obtaining a CLOMR which will seek to remove most of the floodplain from the Painted Hills site based on the proposed flood conveyance facilities and fill. Under the CLOMR process FEMA evaluates the hydrologic or hydraulic characteristics of a flooding source on a site or sites and the result of modifications of the existing regulatory floodway, the effective Base Flood Elevations (BFEs), or the Special Flood Hazard Area (SFHA). The letter is a conditional authorization to amend the NFIP map. Once land modifications are completed, the applicant must request a LOMR to the Flood Insurance Rate Map (FIRM) to finalize the removal of specific areas from the 100-year floodplain designation. "As-built" certification and other data must be submitted to support the revision request. Under Alternatives 2a and 2b, the FEMA’s CLOMR/LOMR process would result in the removal of approximately 48 acres of FEMA-designated 100-year floodplain from the Painted Hills site, and another 44 acres of 100-year floodplain from off-site properties. (See Figure 3-8, Alternatives 2a and 2b - Existing and Future Floodplain Areas.) As noted on this figure, the entire off-site area immediately east of Madison Road currently designated as 100-year floodplain would lose its floodplain designation and the impact of the potential for ponding in that area from floodwaters would be effectively eliminated. Alternatives 2a and 2b would also remove the currently designated floodplain between the northeast corner of the Painted Hills site and SR 27, including the Gustin property. The 100-year floodplain will be removed from most of the site, with the exception of portions of the northwest corner. The proposed multifamily development is located adjacent to an area that will remain in the mapped flood hazard area. As currently designed, the access route to this multi-family is located in the flood hazard area. Final design of the northwestern corner of the PRD site will ensure an access route to the proposed multi-family development that is outside of the flood hazard area, consistent with fire and emergency service design standards. The intent of the floodwater conveyance system is to permanently remove most of the flood hazards that currently exist both on and in the vicinity of the Painted Hills site. The capacity and redundancies built into the proposed flood conveyance system will have the positive impact of preventing flooding. Concerns regarding the risk to health and human safety in the event of a failure of the flood conveyance system were raised by agency staff and public commenters. In consideration of this concern, the project design team critically reviewed the potential for failure of various elements of the system, in particular elements that are critical to the intake and outflow of floodwaters. Because the on-site flood conveyance has a singular intake for floodwaters at the headworks—as opposed to the broad infiltration basin with multiple drywells and outflow pathways—it was determined that the headworks represented the most critical element to flood mitigation and would create the greatest off-site impact if it were to fail. As a consequence, WEST performed modeling to evaluate the peripheral areas that would be subject to inundation to help determine the risk associated with a complete obstruction of the headworks. Painted Hills Residential Development | Spokane Valley, Washington Page 36 Final Environmental Impact Statement With its model, WEST compared flood inundation in a headworks failure scenario to the current 100-year floodplain to determine the extent to which off-site properties would be impacted under Alternatives 2a and 2b in the unlikely event that a total obstruction of the headworks occurs. As noted in Appendix N, off-site areas subject to inundation under a total headworks failure scenario are largely the same as areas subject to inundation in a No Build Scenario (Alternative 1). Under a complete headworks failure scenario, approximately 6.89 acres of off-site properties experience reduced flood risk compared to inundation represented in present day FEMA 100-year floodplain mapping. Comparatively, 1.09 acres of off-site property could potentially experience flooding that wouldn't otherwise see flooding under present 100-year flood conditions. Therefore, some increased flooding would occur beyond present day conditions in limited areas under a total headworks failure, but the majority of the area subject to inundation in a headworks failure scenario will be the same as present day 100-year flooding conditions. Redundant safety features and operations and maintenance of the flood conveyance system are therefore critical to minimize risk to off-site properties in the vicinity of the Painted Hills PRD. One potential adverse impact that could result from the removal of the FEMA floodplain designation from the Painted Hills site or off-site properties could be that the implementation of the flood conveyance system provides a sense of security to potential homebuyers, encouraging them to purchase a home on a site they believe to be safe from flooding. In the unlikely event that the flood conveyance infrastructure fails, these homeowners could be temporarily displaced until the system failure is remedied and flood damage is repaired. Potential points of failure associated with the proposed flood conveyance infrastructure and related impacts are discussed in detail later in this section. Under Alternative 2a, floodwaters would be controlled and managed, and compensatory storage requirements would be addressed on the Painted Hills site through a combination of enhanced conveyance facilities (culverts and pipes), infiltration galleries, and imported fill. Overflows from the Chester Creek channel on the south side of Thorpe Road would be conveyed north under the road through a new 30-foot long by 3-foot-deep box culvert with capacity to pass 500-year flood flows along the Golf Course Overflow Path without overtopping Thorpe Road. This new box culvert would replace the existing set of three, undersized 15-inch culverts. On the north side of the new box culvert, floodwater would enter an open channel that connects to a sloped headwall holding two 48-inch concrete pipes. These pipes would have capacity to convey flood volumes up to the 500-year flood. The two 48-inch pipes would extend north for approximately 2,100 feet along Madison Road and would intercept and convey water from four existing 18-inch culverts that convey water from the Madison Hills under Madison Road. These connections would allow the design flow rate of 15 cfs from the Madison Hills to be added to the 91 cfs, for a total design flow rate of 106 cfs (the 100-yr levee-failure scenario). Painted Hills Residential Development | Spokane Valley, Washington Page 37 Final Environmental Impact Statement Figure 3-7: Proposed Drainage Features Painted Hills Residential Development | Spokane Valley, Washington Page 38 Final Environmental Impact Statement Figure 3-8: Alternatives 2a and 2b – Existing & Future Floodplain Areas Painted Hills Residential Development | Spokane Valley, Washington Page 39 Final Environmental Impact Statement The two 48-inch pipes would end at a vertical headwall where the floodwater would be released onto a concrete pad and flow across a level spreader into a sloped, 269 cfs capacity biofiltration swale. Suspended solids in the floodwater would be filtered out by tall grasses planted in the biofiltration swale. At the end of the biofiltration swale, the water would enter a settling pond where additional suspended sediments would precipitate to the floor of the pond. Water would be retained in the settling pond until the pond depth exceeds 1 foot, at which point the water would flow through two 48-inch pipes into either a 1.4 or 9.3-acre infiltration pond that would be 2 feet below the elevation of the rock weir. The biofiltration swale, settling pond, and infiltration pond will be designed to meet standards of the SRSM and Ecology’s Stormwater Management Manual for Eastern Washington (SWMMEW). The floodwater infiltration system is designed to eliminate flooding impacts by ensuring that floodwater can infiltrate on-site under normal ground conditions as well as in situations where the ground is frozen and infiltration through the ground is not possible or is extremely limited. Under normal conditions, floodwater will have the opportunity to infiltrate through all permeable surfaces after exiting the two 48-inch pipes, including the biofiltration swale, the settling pond, the infiltration pond, and the gallery containing the dry wells. The infiltration pond has an outflow capacity of 730.43 cfs as provided in WCE’s flood control narrative (Appendix P). When the ground is frozen and infiltration through the ground surface is reduced and water levels within the infiltration basin rises by 1 foot in elevation, the water would crest over the rims of the 50 individual drywells and infiltrate into the native soils. The drywells would have a combined design capacity of 52.5 cfs, per the IPEC infiltration rate. Under Alternative 2a, the flood conveyance system has been designed to convey floodwater from a 100- year event in which a concurrent failure of the existing non-certified levee upstream of Thorpe Road occurs. Conveyance of floodwater during a 100-year storm in which the non-certified levee fails is feasible due to enlarged conveyance pipes, designed to include a “factor of safety” that assumes a greater capacity (145 cfs) than the modeled design storm (106 cfs) (WEST CLOMR, 2022). In addition to managing the impacts of floodwater from off-site that enters the Painted Hills site, Alternative 2a would also modify the Gustin Ditch located off-site to the northeast of the Painted Hills site, from an open ditch to a 36-inch pipe, to eliminate the potential for floodwater entering the site from sources to the east. The piping of the Gustin Ditch would remove the future possibility of the ditch flooding the lowlands to the south if the south embankment were to fail as depicted in the FEMA FIS. Alternative 2a would also deepen the triangle pond detention basin and install 18 new drywells in the pond bottom to increase the infiltration capacity of the pond and to further protect against potential flooding of the area west of SR 27 and east of the Painted Hills site. The implementation of Alternative 2a will require the flood hazard management system to remain in optimal condition in perpetuity. For conservative planning purposes, each element of the system has been designed to accommodate more floodwater than the design storm. The 48-inch pipes that convey Chester Creek overflow water to the infiltration basin at the north end of the site and the infiltration basin itself are of particular importance to the function of the overall floodwater conveyance system. To ensure that these conveyance pipes have sufficient capacity to convey floodwaters on the site, they have been designed to accommodate a “factor of safety” that assumes a greater capacity (145 cfs) than the modeled design/100-year storm (106 cfs). These pipes have been specified and designed to ensure a 100-year lifespan. The infiltration basin installed with both Alternatives 2a and 2b has been designed to infiltrate 290.76 acre-feet over a period of weeks, and the dry well galleries have been included in the design to effectively infiltrate the peak flow rate of the 100-year storm for when the infiltration capacity of the basin is compromised due to partially frozen ground conditions. The dry wells, which extend down to a depth of 12 feet below the finished ground surface have been designed with standpipes that will extend up to one foot above the pond surface to ensure that the inlets will be above any frozen surfaces and floodwaters will continue to infiltrate through the dry wells even in partially frozen ground condition situations. Painted Hills Residential Development | Spokane Valley, Washington Page 40 Final Environmental Impact Statement Individual elements of the proposed flood conveyance system have the potential to fail under extreme circumstances. However, if properly maintained, the likelihood of failure of any one element is small. Each element has been designed to withstand water volumes in excess of the 100-year storm and floodwater conveyance pipes have been sized to accommodate 1.3 and the ponds are sized at 3 times the quantity of water predicted to be produced by the 100-year design storm. While the likelihood of the flood conveyance system failing is very small, the following section describes possible system element failures, the location of potential failures, the range of severity of such failures, and the risks posed to the Painted Hills site and off-site properties from such failures. Extreme yet unlikely circumstances potentially leading to system failure include earthquakes, volcanic eruptions, extreme flood events (500-year or greater flood), intentional damage due to vandalism, and long- term failure to maintain system elements. The severity of the impacts resulting from system failure would depend upon the degree of failure. Minor malfunctions such as a leaking or partially blocked conveyance pipes would likely result in localized ponding or minor flooding in the immediate vicinity of the malfunction. Complete failure of one of the system elements, such as the headworks, during an extended, extreme flow event could result in major property damage and possibly human injury both on and off site. Appendix E includes a summary table that includes the flood conveyance system elements that, if compromised or failed, would have the potential to result in the flooding of peripheral areas. Figure 3-9 illustrates the locations of these flood conveyance system elements. Painted Hills Residential Development | Spokane Valley, Washington Page 41 Final Environmental Impact Statement Figure 3-9: Painted Hills Flood Conveyance System Element Locations Painted Hills Residential Development | Spokane Valley, Washington Page 42 Final Environmental Impact Statement Phasing Under Alternative 2a, the flood management improvements would be constructed in the first phase of Painted Hills development before any new residential or commercial development would be initiated. The first phase would include all improvements for managing floodwaters that enter the Painted Hills site from off-site sources. Specifically, it is expected that the following improvements would occur in Phase 1:  Excavate the park area and infiltration basin area and use the excavated material to fill against the existing levee adjacent to the Chester Creek channel. Fill will be placed by special inspection to the compaction requirements of the geotechnical engineer.  Excavate infiltration basin and place fabric, rock, and drywells  Form final contours of the park area, infiltration basin, settling pond, and bioswale. Seed and establish proposed grasses on the bottom of these features and on sloped surfaces.  Install a 30-foot by 45-foot and 3-foot-deep box culvert in Thorpe Road.  Form concrete open channel and headwall.  Install two (2) 48-inch pipes along the west side of Madison Road with manholes at connection points to 18-inch culverts that will receive stormwater flows from the east side of Madison Road. In addition to these improvements, it is anticipated that Phase 1 would include the clearing and grubbing of future Painted Hills site development areas, including the removal of the existing organic soil layer in the northeast corner of the site to expose the more-permeable gravel layer located immediately below it. The cleared soil will be stockpiled on site and erosion control measures would be implemented consistent with the local grading and National Pollutant Discharge Elimination System (NPDES) construction stormwater permitting requirements for the Painted Hills project. Under Alternative 2a, after the Painted Hills site has been cleared, the southern open space area would be excavated, creating a depression that would serve as a temporary repository to capture any floodwater that enters the Painted Hills site during this initial construction phase. Following the excavation of the southern open space depression, excavation of the infiltration basin on the north end of the Painted Hills site would be completed. The capacity of these two basins would be designed to capture and infiltrate a 100-year storm event. The material excavated to create the two basins would be evaluated for its suitability as fill material and if it is deemed suitable, would be placed along the existing on-site levee east of the main channel of Chester Creek to bolster the flood protection capacity of this existing non-certified levee and begin the overall filling of the Painted Hills site. Potential for Failure The implementation of Alternatives 2a and 2b will require the flood conveyance system to be maintained in perpetuity. For conservative planning purposes, each element of the system has been designed with a “factor of safety” that ensures marginal greater capacity than the design storm (e.g., 100-year storm) volumes. In addition to each element of the system being designed to accommodate more water than the design storm, each element of the system is designed to have redundant safety features in the event an element fails, thereby reducing the likelihood of complete system failure and risk to adjacent properties. A description of redundant safety features is provided below and supplemented by the conceptual flood conveyance system diagram included with this FEIS as Appendix K. The primary and most vulnerable aspect of the flood conveyance system is the headworks located north of Thorpe Road, through which floodwaters entering the site from under Thorpe Road reach the floodwater conveyance system, as shown in Appendix K. In a worst-case scenario, debris could collect and fully obstruct Painted Hills Residential Development | Spokane Valley, Washington Page 43 Final Environmental Impact Statement the headworks, preventing floodwaters from entering the flood conveyance system. The only known source of debris that could cause such a failure would be vegetative debris and the only known type of debris that would be expected to fully obstruct the headworks is large woody debris (e.g. fallen trees). To examine the potential for large woody debris to reach the headworks, it is important to review and consider the vegetative condition of the upland basin that contributes floodwaters to the site. In this case, vegetation in the upland basin is predominated by pasture grasses with noted absence of large trees that would be vulnerable to falling and being carried downstream via floodwaters. Thus, the basin that contributes floodwater to the site predominantly lacks the vegetative condition that would have the potential to send large woody debris to the headworks location. In addition, flood velocities and shallow flood depths that reach the site are not conducive to carrying large woody debris. Under the current HEC-RAS modeling, 100-year floods average 0.6 ft deep (max depth 0.9 ft) and average velocities of 1.4 feet per second (ft/s). Similar depths and velocities were observed under the HEC- RAS modeling for the 500-year flood event, with average depths of 0.6 ft (max average depth of 1.0 ft) and average velocities of 1.5 ft/s. Therefore, modeled depths and velocities under the 100-year and 500-year storm events lack the velocities and depth required to carry large woody debris capable of obstructing trash racks at the headworks. Flood waters could potentially transport some grass and sediment, both of which are able to flow through the angled trash racks and continue to the next element of the flood conveyance system without issue. Average flood depths and velocities under the 100-year and 500-year storm event are identified in Appendix N. Despite the general absence of floodwater volumes, velocities, and large woody debris necessary to create a failure event at the headworks, the PRD project has incorporated a secondary storage area that could receive floodwaters in the event of a headworks obstruction event. If such an event were to occur, floodwater would crest over the open channel wall and flow into the adjacent approximately 4-acre open space area within the PRD. This open space area will function as a secondary storage pond and temporary containment measure. The secondary storage area is overdesigned in the event of headworks failure. Specifically, the flood control narrative prepared by WCE on March 6th, 2019, provides the following analysis: “This 176,181 square foot secondary storage pond serves as a secondary measure of protection and a detention facility at the south end of the project in an area designated as future park space. Below the rim of the catch basin, the detention facility has a holding capacity of 178,699 cubic feet (cf) or 4.10-acre feet, at a final grade of five feet depth the detention facility has an ultimate holding capacity of 943,866 cf or 21.67-acre feet. As such, the area of the secondary storage park pond will be covered with grass turf and will function as park open space, with a gentle 3:1 slide slopes for easy access and maintenance.” A copy of the flood control narrative is included with the FEIS as Appendix P. Due to the prominence and visibility of the 4-acre open space area within the PRD, it is expected that overflows into this secondary storage area would be apparent to those living within the Painted Hills PRD and to the Homeowners Association representatives responsible for managing the maintenance of the system, triggering a maintenance crew to come to the site to remove any debris causing an obstruction. Therefore, the secondary storage park pond, while not designed for disposal of floodwater, will serve as a secondary containment area, detain floodwaters, and drain floodwater back into the flood conveyance system. In the event that a total obstruction of the headworks was not addressed by maintenance crews, floodwaters during 100-year and 500-year events would exceed the capacity of the secondary storage pond and would cause flooding on off-site properties, predominantly in the same areas that are subject to 100-year and 500-year inundation under the No Build alternative. WEST Consultants, the applicant’s flood and hydrology consultant, has modeled a total failure event at the headworks and the resulting inundation, included with this FEIS as Appendix N. During flood events floodwater will continue through the headworks and through dual 48-inch pipes to a grassy slope to filter sediment prior to entering the settling pond. To convey floodwater to infiltration basin, two (2) Painted Hills Residential Development | Spokane Valley, Washington Page 44 Final Environmental Impact Statement 48-inch culverts are located within a berm on the downstream side of the settling pond. Water in the infiltration basin will percolate to groundwater through the surface of the pond and/or through approximately 50 drywells which exist to ensure that water can continue to infiltrate even during frozen ground conditions. The discharge pond and drywells are designed to accommodate more flood water than a design storm. Offsite flood conveyance elements, including the triangle pond and Gustin Ditch, are designed to accommodate approximately 2.25 times the peak 100-year storm flows coming from the east before entering the project site. The triangle pond is planned to be regraded for tiered areas and elevations as follows: 17,060 square feet at an elevation of 1,990, 35,812 square feet at an elevation of 1,995, and 84,416 square feet at an elevation of 2,000. Additionally, the triangle pond will have 18 drywells consistent with the City of Spokane Valley Standard Plan S- 101 and Spokane County’s Regional Stormwater Manual (April 2008). Similar to the drywells within the on-site infiltration pond, the drywells within the triangle pond have been designed to allow floodwater infiltration during frozen ground conditions. In the event of complete failure of the on-site headworks during a design storm, floodwaters would generally remain within the current effective FEMA floodplain boundary, as shown in the headworks failure Appendix prepared by WEST Consultants (Appendix N). Thus, as illustrated in the figures presented in Appendix N, the flood conveyance system significantly reduces flooding risk in the area even in the event of a complete failure of the headworks. Given the absence of woody debris conditions in the upstream watershed, low flood volumes and shallow flood depths to carry large woody debris, the overdesign of each flood conveyance element and secondary safety features, catastrophic flood system failures are highly unlikely to occur, particularly with the implementation of regular maintenance consistent with the draft O&M manual for these facilities. If a total failure were to occur, the most likely location would be at the headworks as illustrated in Appendix K prepared by Whipple Consulting Engineers. As modeled by WEST Consultants and illustrated in the figures in Appendix N, off-site areas of 100- year flood inundation in a total headworks failure scenario closely correspond to existing 100-year flood inundation areas under current conditions. Flood Management Facilities and Maintenance Operations and maintenance activities of the flood conveyance system and structure of the HOA are the same under alternatives 2a and 2b. According to the manufacturers’ specifications, the anticipated useful life of the conveyance pipes and drywells is 100 years. Because the conveyance pipes will be mostly underground and will not be exposed to the effects of weathering, their useful life is likely greater than 100 years. HOA Structure and Responsibility In order to maintain common areas within the PRD site and on-site and off-site flood conveyance infrastructure, a Homeowner’s Association (HOA) will be established consisting of the owners of each residential, multi-family, and commercial lot within the Painted Hills PRD project. This HOA will be responsible for the continued operation and maintenance, including repair and replacement as needed, of these facilities. The HOA will require monthly contributions from all members. In addition to funding the regular and routine maintenance of all open space areas within the PRD, these monthly contributions will establish a reserve fund only allocated for the operation and maintenance of the flood conveyance system. In the event that flood conveyance infrastructure needs maintenance or repair on or before the PRD site is fully occupied and before full capitalization of the reserve fund is established, a maintenance bond will be in place by the developer of the site and that, upon full project buildout, the bond will be maintained annually by the HOA to supplement the reserve fund. The bond will be structured to allow the City and/or a future flood improvement district, if created, to access funds to perform operation and maintenance responsibilities on the flood control system if deemed necessary. Painted Hills Residential Development | Spokane Valley, Washington Page 45 Final Environmental Impact Statement The maintenance responsibilities of the apartment owner and HOA contractor will include the off-site improvements at the Gustin Ditch and triangle pond. The reserve fund will be used to fund services to maintain the on-site and off-site infrastructure. The HOA will maintain a contract with a licensed third-party vendor to conduct all system maintenance as stipulated by a final Operations and Maintenance (O&M) Manual, which will be required prior to the release of on-site and off-site construction approvals from the City and County. As the project develops and ownership of parcels is transferred from the developer to individual owners on the site, the developer will bear proportionate responsibility for maintaining the floodwater and stormwater management systems. The final O&M Manual will include a “Painted Hills Residential Development Flood Conveyance System & Plat Amenities Plan” that will provide detailed descriptions of how the facilities will be maintained and will include provisions for establishing and maintaining the reserve fund through regular HOA member deposits. The final O&M Manual will also stipulate that the HOA maintain a maintenance bond to ensure that resources are available in perpetuity for all system maintenance requirements that might exceed the reserve fund capacity. Future costs could include planned and unplanned operation and maintenance costs along with future replacement costs for the storm drainage facilities. A draft version of the O&M manual is included with the FEIS as Appendix O. The final O&M Manual will include a provision that requires the HOA to provide an annual report to the Spokane Valley Public Works Department describing the general status of the reserve fund account, and describing specific inspections, findings, and maintenance performed. Spokane County and the City and their authorized agents would be granted access rights for routine inspection and emergency repairs of the flood conveyance facilities but would not incur the responsibility to perform these functions at any time. At any point in the future, should the City or County wish to establish a flood control district that encompasses the PRD site, the PRD will enable this through the recording of “waivers of remonstrance” on the title of each lot within the PRD. These waivers of remonstrance will preclude objections from current and future owners of lots within the subdivision to the formation of the district. This would enable the City or County form a flood control district in an event in which the HOA is dissolved or deemed delinquent on monitoring, maintenance, and operation activities for the flood conveyance system. It is anticipated that the requirement for waivers of remonstrance to be recorded on the title of lots within the PRD will be a condition of approval of the City PRD application. Monitoring and maintenance activities of the Painted Hills PRD will be the responsibility of the Painted Hills PRD HOA or contracted entity. Monitoring and maintenance activities are listed as mitigation measures in Section 3.2.3 of the FEIS. Adequacy of the Reserve Fund Funding for the continued operations and maintenance of the flood conveyance system will be provided through a reserve fund, funded by monthly HOA dues. Under the CC&R provisions for the PRD, penalties will be imposed on owners within the PRD who fail to pay HOA dues. These penalties include the ability of the HOA to file liens on the properties and the ability of the City to withhold building or other requested permits for property owners on non-compliant properties. Until the HOA is fully subscribed by new owners within the PRD during project buildout, the project developer will be responsible for ensuring a minimum annual reserve fund balance. The minimum annual reserve balance will be established in the final O&M manual as a condition of approval and recorded in the final plat process in accordance with the city’s requirements. This is in addition to maintaining an initial performance bond to Painted Hills Residential Development | Spokane Valley, Washington Page 46 Final Environmental Impact Statement ensure the flood conveyance infrastructure is completed to the specifications and standards of the construction document set and CLOMR design package. The reserve fund for maintenance, repair and replacement of flood conveyance infrastructure will be based on estimated future replacement costs that are converted to annual costs (or deposits) per the following calculation as discussed in the draft O&M manual (Appendix O). The costs assume inflation and interest rates, which will be reviewed and adjusted on an annual basis consistent with current financial conditions. The funds anticipate that the first potential system repair would occur approximately 20 years from the day of establishment. The adequacy of the reserve fund, both in terms of future replacement costs and in terms of how much money needs to be deposited each year to maintain the system is provided in the draft O&M Manual (Appendix O), and follows the calculation method noted below: 1) Estimate the value that the item will have in the future when it is time to replace it using the following equation: FV=PV*(1+i1)n, where: FV = future value PV = present value i1 = inflation rate n = number of years to replacement 2) Estimate how much money will be needed to be deposited each year in the reserve fund in order to have enough money accumulated in time to pay for the replacement using the following equation. A=FV* i2 / [(1+ i2 )n -1], where: A = annual payment (or deposit) FV = future value (stee step one, above) i2 = interest rate n = number of years to replacement The following values are the results of the calculations which are shown on pages 14 through 17 of the draft O&M manual (Appendix O).  Annual Cost for regular operation and maintenance: $152,392  Annual cost for replacements: $76,979  Total annual costs: $229,370  Total monthly costs (=total annual costs/12 months): $19,114.18  Number of units (SF lots +MF lots) + (Commercial): 596 + (18,400 SF/100SF) = 615  Monthly cost per lot (=total monthly costs/ # lots): $31.08  Total annual cost per lot/unit: $372.96 Several enforcement mechanisms will be specified in the CC&R’s and on the finalized and recorded final plat to ensure fees are paid towards the reserve fund and the system is maintained is accordance with the City and County’s requirements. These enforcement mechanisms are anticipated to include but are not limited to late fees and citations imposed on delinquent/defaulting property owners, property liens, and a moratorium on any new development requests from such property owners reviewed through the HOA’s architectural review board and/or with the City and County Planning Department. The O&M manual and reserve fund calculations will be revised and updated as necessary or on an annual basis to account for actual expenses and changes in rates and/or inflation. The developer anticipates that the completion and recording of a final O&M manual will be a condition of approval prior to City and County approval of on-site and off-site infrastructure. The O&M manual would be finalized and recorded in the final plat process in accordance with the city’s requirements and pursuant the Code of Federal Regulations (CFR) Title 65.6 (a)(12). Painted Hills Residential Development | Spokane Valley, Washington Page 47 Final Environmental Impact Statement 3.2.2.3 Alternative 2b – Planned Residential Development-Low Infiltration Sources and Extent of Floodwater The sources and extent of floodwater that have been known to enter the project site in the past will be the same for Alternative 2b as Alternative 2a. Floodplain Map Modifications and Floodwater Management Improvements The floodplain map revision for on-site and off-site areas for Alternative 2b would be identical to Alternative 2a. Under Alternative 2b, the floodplain map revision process would eventually result in the removal of approximately 48 acres of FEMA-designated 100-year floodplain from the Painted Hills site, and another 44 acres of 100-year floodplain from off-site properties. As described previously, the 100-year flood hazard area designation will be removed from the majority of the site, with the exception of the portions of the northwest corner. The proposed multifamily development is located adjacent to an area that will remain in the mapped flood hazard area, and as currently designed the access route to this multi-family is located in an area that will continue to be designated as flood hazard area. Final design of the northwestern corner of the PRD site will include a safe access route to and from the proposed multi-family development. Under Alternative 2b, as with Alternative 2a floodwater impacts would be controlled and managed, and compensatory storage requirements would be addressed at Painted Hills on-site through a combination of enhanced conveyance facilities (culverts and pipes), infiltration galleries, and imported fill. The only difference between the floodwater management systems associated with Alternative 2a and Alternative 2b is that under Alternative 2b, in order to accommodate the lower infiltration capacity of the native soils, the infiltration pond would occupy 9.3 acres, which is 7.9 acres more than the Alternative 2a infiltration pond. A potential impact of removing Painted Hills on-site and off-site properties from the FEMA 100-year floodplain is that these properties would no longer carry the requirement for flood insurance. Therefore, homeowners within the Painted Hills site and off-site property owners could experience uninsured property damage if the flood conveyance system were to fail catastrophically. Proposed system design and operational and maintenance protections are discussed throughout this document to minimize the potential for such system failures. Phasing As described for Alternative 2a under Alternative 2b, the flood management improvements would be constructed in the Phase 1 of development. Phase 1 would include all improvements for managing floodwaters that enter the Painted Hills site from off-site sources. As described for Alternative 2a under Alterative 2b, it is expected that the following improvements would occur in Phase 1:  Excavate the infiltration basin area and use the excavated material to fill against the existing levee adjacent to the Chester Creek channel. Fill will be placed by special inspection to the compaction requirements of the geotechnical engineer.  Excavate infiltration basin and place fabric, rock, and drywells. Painted Hills Residential Development | Spokane Valley, Washington Page 48 Final Environmental Impact Statement  Form final contours of the park area, infiltration basin, settling pond, and bioswale. Seed and establish proposed grasses on the bottom of these features and on sloped surfaces.  Install a 30-foot by 45-foot by 3-foot-deep box culvert in Thorpe Road.  Form concrete open channel and headwall.  Install two (2) 48-inch pipes along the west side of Madison Road with manholes at connection points to 18-inch culverts that will receive stormwater flows coming from and the east side of Madison Road.  The Gustin Pipe and Triangle Pond construction as an offsite improvement will be constructed as a part of the first construction phase. If the construction of the flood conveyance system has to be phased over a winter season, and a flood occurs during construction, construction staging, and sequencing will provide conveyance pathways, storage and outflow opportunity for floodwaters in such an event. As the infiltration basin is located in the regional low point, whatever level of flood event occurs will continue to gravity flow to the excavated pond. The floodwaters would travel as they currently do or within portions of the completed construction. It is not anticipated that construction activities will redirect floodwater where it has not been currently mapped. Further, FEMA floodplain mapping will not be revised, pursuant to a final map revision (LOMR), until all system infrastructure and grading is in place and this condition has been documented and certified as an as-built condition by FEMA. Flood Conveyance Facilities and Maintenance The flood conveyance facilities, the system maintenance requirements, and potential impacts associated with Alternative 2b would be identical to those for Alternative 2a. 3.2.3 Mitigation Measures Under Alternatives 2a and 2b, the following mitigation measures will be required to control potential impacts from floodwaters on the built environment.  An HOA would be established for the purpose of managing a short- and long-term maintenance program for open spaces and infrastructure throughout the Painted Hills project, including the on-site and off-site flood and stormwater infrastructure.  An initial settlement amount will be deposited to establish the reserve fund and provide one year of maintenance for the flood conveyance system during Phase I construction. Following the completion of Phase I construction and all system infrastructure necessary to secure the final FEMA map revision, ownership and maintenance responsibility for flood system infrastructure will be transferred to the HOA. An O&M Manual will be established for the HOA and will govern the management and maintenance of all stormwater and floodwater management facilities. This O&M Manual will provide detailed maintenance requirements for all critical storm and flood water infrastructure elements, which include: o Vegetation and erosion control maintenance of all on-site open space areas o Catch basins and stormwater manholes throughout the project o Cross culverts (18-inch) and flap gates from Madison Road o Bio-infiltration swale Painted Hills Residential Development | Spokane Valley, Washington Page 49 Final Environmental Impact Statement o Roadside swales o Settling pond o Infiltration pond and drywells o Access roads and parking pads (to allow for the parking of maintenance vehicles) o 36-inch storm pipe within the Gustin Ditch (off-site improvement) o Triangle pond improvements including drywells and gravel access maintenance road  The HOA will review and revise the reserve fund calculations established in the O&M manual if/as necessary once the actual cost of operation and maintenance items are contracted in accordance with the city’s requirements and pursuant the Code of Federal Regulations (CFR) Title 65.6 (a)(12).  The HOA will be responsible for securing a “contracted entity” (CE) for long-term maintenance of critical infrastructure. Responsibilities of the CE will include: o Annually inspecting the pipe openings on each end to ensure there is no blockage or damage to the ends. o Every three years or after substantial runoff, performing a Telescoping Video (TV) inspection of the pipe looking for blockages, damage, etc. Visual inspection can be made at pipe manhole locations by authorized maintenance personnel. o Removing sediment build-up from the 48-inch pipes installed with the project. o Repairing any sections of damaged pipe. o Visually inspecting the concrete channel, headwalls, and trash racks for damage or corrosion that would compromise the trash rack integrity twice per year. o In August or September of each year, prior to each rainy season, inspect each trash rack to ensure that there is no debris present and, if so, clear the debris. o Following large storm events or rapid snow melt events perform a visual inspection and remove any deleterious debris and trash.  A HOA Reserve Fund for the repair and maintenance of critical floodwater management infrastructure will be established and maintained in perpetuity to ensure the long-term viability and capacity of the HOA to maintain the critical flood infrastructure. The required maintenance and replacement items for floodwater infrastructure will be included in a final O&M Manual adopted prior to City approval of the final plat. A performance surety bond will be required by the City during the construction of the facility to ensure its completion.  A maintenance bond will be secured by the HOA and maintained in perpetuity to ensure the long-term financial capacity of the HOA to maintain and repair various flood system improvements. The bond will be structured to allow the City and/or a future flood improvement district, if created, to access funds to perform operation and maintenance responsibilities on the flood control system if deemed necessary.  Proposed flood conveyance infrastructure is designed to allow access to all residential development in the event of a 100-year flood. Painted Hills Residential Development | Spokane Valley, Washington Page 50 Final Environmental Impact Statement  A waiver of remonstrance will be recorded on all lots within the PRD. This waiver will require all owners of lots within the PRD to sign and acknowledge the ability of the City, County or other governmental agency to form a flood control district at any time that would assume ownership, maintenance and repair responsibility from the HOA for the on-site and off-site flood conveyance infrastructure associated with the PRD. Further, the waiver would waive the ability of that owner to protest to the formation of such a district. Lastly, it would acknowledge that, as a part of the flood district formation, HOA reserve funds intended for flood conveyance system maintenance will be made available to the flood control district to the extent allowed under local, state and federal laws. City acceptance of the waiver of remonstrance language will be a requirement before a final plat is recorded.  An advisory note informing buyers of flood risk should the flood conveyance system fail will be added as a note to the final plat document. 3.2.4 Indirect Effects Potential indirect effects could result from the removal of the 100-year floodplain designation from approximately 44 acres of off-site properties. By reducing regulatory and financial barriers to development of these off-site properties, Alternatives 2a and 2b could indirectly enhance and facilitate the development of these off-site properties, which are predominantly zoned for low density residential use by the City and County. Environmental impacts of those off-site developments would be addressed through individual local regulatory and SEPA reviews. 3.2.5 Cumulative Effects No cumulative effects are anticipated when considering the proposed action alternatives and other activities in the project vicinity. Painted Hills Residential Development | Spokane Valley, Washington Page 51 Final Environmental Impact Statement 3.3 TRANSPORTATION A traffic impact analysis (TIA) was completed on September 14, 2016, by WCE for the Painted Hills PRD project. The TIA is incorporated into this FEIS by reference and includes detailed information regarding existing (2015) and future (2025) traffic conditions surrounding the Painted Hills site. A copy of the TIA is included with this FEIS as Appendix F. Future traffic conditions were reported both with and without implementation of the Painted Hills PRD project to determine the extent to which the PRD project may contribute to level-of-service (LOS) deficiencies on the local transportation network. The TIA uses trip generation estimates for the Painted Hills project based on specific land use code categories per 1,000 square feet of floor area (KSF) from the Institute of Transportation Engineers (ITE) Trip Generation Manual, 9th Edition. From those estimates, the TIA evaluates how study intersections perform under current and future conditions relative to city-adopted LOS standards. The land uses designated for the project in the TIA and the corresponding ITE codes are provided in Table 3-1. Table 3-1: Transportation Impact Analysis Land Use Types (TIA Table 5) Description Number of Units / KSF ITE Land Use Code Cottage Style Single Family Lots 52 Units Residential Townhouses — 230 Single Family Residential 206 Units Single Family Residential — 210 Single Family Residential Estate Type 42 Units Single Family Residential — 210 Apartments 228 Units Apartments — 220 Apartments (mixed use) (North) 52 units Apartments — 220 Commercial Development (North) 13.4 KSF Shopping Center — 820 Commercial Development (South) 9.0 KSF Shopping Center — 820 Existing Restaurant (South) 4.0 KSF Quality Restaurant — 931 To supplement the 2016 TIA, WCE prepared a letter, dated November 13, 2018, addressed to Ray Wright at the City, which concludes that the traffic volumes recorded for the Painted Hills PRD in the 2016 TIA remain reasonably accurate (with a variation of approximately one percent or less in volume) based on recent traffic counts collected. Therefore, the findings from the 2016 TIA continue to present a reasonable assessment of the expected impacts of the Painted Hills PRD on the surrounding road network. A summary of the 2016 TIA findings is described further below. The standards below are established by the City consistent with Chapter 5 of the Spokane Valley Comprehensive Plan and Chapter 3 of the Spokane Valley Street Standards. LOS designations provide a means for evaluating operational performance of intersections. As identified in Figure 29 of the Spokane Valley Comprehensive Plan, LOS designations are described as noted in Table 3-2. Painted Hills Residential Development | Spokane Valley, Washington Page 52 Final Environmental Impact Statement Table 3-2: Level of Service Descriptions Level of Service Description A Free-flowing conditions B Stable operating conditions C Stable operating conditions, but individual motorists are affected by the interaction with other motorists D High density of motorists, but stable flow E Near-capacity operations with speeds reduced to a low but uniform speed F Over capacity with long delays As noted on page 5-85 of the Spokane Valley Comprehensive Plan, the City requires the following minimum LOS within the City:  A minimum of LOS D is required for major arterial corridors.  A minimum of LOS D is required for signalized intersections not on major arterial corridors.  A minimum of LOS E is required for unsignalized intersections (LOS F is acceptable if the peak hour traffic signal warrant is not met). 3.3.1 Affected Environment 3.3.1.1 Study Area The overall transportation network in the vicinity of the Painted Hills site consists of a state route, urban principal arterials, collectors, and local access roads as described below. Dishman-Mica Road extends south and southeast from Sprague Avenue to SR 27, for approximately 7.4 miles. Dishman-Mica Road is a northwest/southeast two-way, two-and five-lane minor-principal arterial. Dishman- Mica Road is an arterial that serves the residential neighborhoods extending from Sprague Avenue to Bowdish Road. Dishman-Mica Road intersects with 8th Avenue, 16th Avenue, 32nd Avenue, University/Schafer Road and Bowdish Road with small commercial uses located at or near the intersections of 16th Avenue, University Road and Bowdish Road. Dishman-Mica Road then winds through a rural area before intersecting with SR 27. Within the study area the posted speed limit on Dishman-Mica Road is 45 miles per hour (MPH). University Road is a north/south, two-way minor arterial, ranging from two to five lanes, that serves a large residential area south of Interstate 90. It runs south from Nora Avenue and crosses several major arterials until it intersects with Dishman-Mica Road. University Road, between Mission Avenue and Sprague Avenue, is a three-lane roadway. From Sprague Avenue to 4th Avenue, it transitions to a five-lane roadway. South of 4th Avenue to Dishman-Mica Road, it reduces to a four-lane roadway and continues to Dishman-Mica Road where the roadway transitions into Schafer Road. University Road is posted at a 35 miles per hour (MPH) speed limit within the study area. The University Road section includes bike lanes from 16th Avenue to Mission Avenue, and sidewalks from Dishman-Mica Road to Mission Avenue. Schafer Road is a north/south, two-way, two-lane, collector that serves a large residential area south of Dishman-Mica Road. Schafer Road runs south from Dishman-Mica Road to 44th Avenue. Schafer Road, between Dishman-Mica Road and 44th Avenue, is a two-lane roadway with shoulders, but no sidewalk or bike lanes. Schafer Road is posted at 35 MPH within the study area. Painted Hills Residential Development | Spokane Valley, Washington Page 53 Final Environmental Impact Statement Bowdish Road is a north/south, two-way, two-lane, minor arterial serving a large residential area south of Interstate 90. Bowdish Road runs south from Mission Avenue and crosses several major arterials until it intersects with Sands Road. Bowdish Road, between Mission Avenue and Dishman-Mica Road, is a two-lane roadway. South of Dishman-Mica Road, Bowdish Road crosses the Union Pacific Railway and becomes a local access roadway. Sands Road branches off Bowdish Road and continues to 44th Avenue. Bowdish Road is posted at 25 MPH on the local access portion, and is posted on the minor arterial as 35 MPH. SR 27 is a north/south, two-way State Highway ranging from two to five lanes. SR 27 extends south from Spokane Valley to Pullman, Washington and serves the many small farming communities of the Palouse. Within the City, SR 27 follows the Pines Road alignment between Trent Avenue and 16th Avenue. South of 16th Avenue, SR 27 shifts to the Blake Road alignment and serves the surrounding urban residential uses and a small cluster of commercial uses at the intersection of SR 27 and 32nd Avenue. From Trent Avenue to 16th Avenue, the posted speed limit is 35 MPH. From 16th Avenue to the 41st Avenue alignment, the posted speed limit is 45 MPH. Beyond 41st Avenue, SR 27 generally has a speed limit of 55 MPH. 16th Avenue is an east/west, two-way, two- and three-lane minor arterial that extends east from Bluff Drive (west of Dishman-Mica Road) through the City to Shamrock Street (South of Shelley Lake). 16th Avenue generally serves residential land uses as well as commercial land uses located at the intersections of arterials. The posted speed limit on 16th Avenue is 35 MPH with the exception of the University Elementary, McDonald Elementary, and Evergreen Jr. High School zones where the posted speed limit is 20 MPH with beacons. The 16th Avenue Road section from Dishman-Mica Road to Sullivan Road includes sidewalks and bike lanes. 32nd Avenue is an east/west, two-way principle arterial ranging from two to four lanes. 32nd Avenue extends east from Dishman-Mica Road to Sullivan Road and serves mostly urban residential uses, but also provides access for commercial uses and University High School. The posted speed limit is 35 MPH with the exception of University High School zone where the speed limit is 20 MPH when children are present. The 32nd Avenue Road section has sidewalks from Dishman-Mica Road to SR 27, and bike lanes from University Road to SR 27. Additional sidewalks and bike lanes are present from Evergreen Road to Best Road. Pines Road is a north/south two-way, two-, three-, and five-lane state route and collector that extends south from Trent Avenue to 40th Avenue. From 16th Avenue to 32nd Avenue, Pines Road is a proposed collector. From 32nd Avenue to 40th Avenue, Pines Road is a collector. Pines Road serves residential uses and a commercial land use located on the northwest corner of Pines Road and 32nd Avenue. The speed limit on Pines Road is 35 MPH, with the exception of the South Pines Elementary school zone, where the speed limit is 20 MPH with flashing beacons. The Pines Road roadway section includes sidewalks along its entire length and includes bike lanes from 22nd Avenue to 32nd Avenue. Evergreen Road is a north/south, two-way urban principle arterial ranging from two to six lanes. Evergreen Road extends south from Indiana Avenue to 32nd Avenue and intersects with eight other minor and major arterials in the City. From Indiana Avenue to Interstate 90, Evergreen Road has six lanes. From Interstate 90 to 4th Avenue, Evergreen Road is a five-lane road. From 4th Avenue to 16th Avenue, Evergreen is a three-lane road. From 16th Avenue to 32nd Avenue, Evergreen Road is a two-lane roadway. The area surrounding Evergreen Road is generally single-family residential uses and small pockets of commercial uses located at or near the arterial intersections. The posted speed limit on Evergreen Road is 35 MPH. Evergreen Road includes sidewalk from 32nd Avenue to 24th Avenue and from 16th to Indiana. Evergreen Road has a bike lane from 32nd Avenue to Sprague Avenue. Sullivan Road is a north/south, two-way, two-, three- and five-lane urban principal arterial that extends south from Wellesley Avenue to just beyond 32nd Avenue. Sullivan Road serves East Valley High School and Central Valley High School, residential, and commercial uses. The posted speed limit is 35 MPH. The Sullivan Road roadway section includes sidewalks and bike lanes from 16th Avenue to 32nd Avenue, and sidewalks from 16th Avenue to Wellesley Avenue. Painted Hills Residential Development | Spokane Valley, Washington Page 54 Final Environmental Impact Statement Madison Road is a north/south, two-way, two-lane collector road that extends south from the intersection of Pines Road and 40th Avenue, which is northeast of the site, through Thorpe Road, until eventually changing into Mohawk Drive. Madison Road is posted at 35 MPH and provides access to residential roads on its east and west side. Madison Road has no sidewalks or bike lanes. Thorpe Road is an east/west, two-way, two-lane collector that extends east from Dishman-Mica Road to Madison Road. Thorpe Road generally serves commercial land uses. The posted speed limit on Thorpe Road is 35 MPH. 3.3.1.2 Existing Conditions Consistent with City procedures, the scope of the TIA as determined after meetings with Public Works staff, the Washington Department of Transportation (WSDOT), Spokane County transportation staff and after the public scoping process, the applicant studied both AM and PM peak hour operations. The AM peak hour data was generally collected between 7:00 AM and 9:00 AM, and PM peak hour data was collected between 4:00 PM and 6:00 PM. For the TIA, the following intersections were studied for level of service performance. See Figure 3-9 for a map illustrating the Traffic Study Intersections relative to the Painted Hills site.  32nd Avenue & University Road  Dishman-Mica Road & University/Schafer Road  32nd Avenue & Bowdish Road  Dishman-Mica Road & Bowdish  Dishman-Mica Road & Apartment. Access (Proposed)  Dishman-Mica Road & Sundown Drive (Proposed)  Dishman-Mica Road & S. Commercial. Access (Proposed)  Dishman-Mica Road & Thorpe Road  Thorpe Road & Commercial. Access (Proposed)  16th Avenue & Pines Road  16th Avenue & SR 27  32nd Avenue & Pines Road  Madison Road & Painted Hills Avenue (Proposed)  Madison Road & 41st Avenue (Proposed)  Madison Road & 43rd Avenue (Proposed)  Madison Road & 44th Avenue (Proposed)  Madison Road & Thorpe Road  32nd Avenue & SR 27 Painted Hills Residential Development | Spokane Valley, Washington Page 55 Final Environmental Impact Statement  32nd Avenue & Evergreen Road  32nd Avenue & Sullivan Road Using methods from the 2010 Highway Capacity Manual as implemented in Synchro, version 9 – Build 902, the TIA reported existing operational conditions as noted in Table 3-3. Because some of the study intersections do not yet exist and would be constructed as a part of the Painted Hills PRD project, those intersections are not included in Table 3-3. Table 3-3: Year 2015 Existing Intersections Levels of Service (Table 2 of TIA) INTERSECTION (S) signalized (U) unsignalized AM Peak Hour PM Peak Hour Delay (sec) LOS Delay (sec) LOS 32nd Avenue & University Road S 11.5 B 11.4 B Dishman-Mica Road &University/Schafer Road S 15.7 B 16.5 B 32nd Avenue & Bowdish Road S 13.1 B 11.7 B Dishman-Mica Road & Bowdish Road S 12.0 B 11.1 B Dishman-Mica Road & Thorpe Road U 10.7 B 10.4 B 16th Avenue & Pines Road U 20.2 C 32.4 D 16th Avenue & SR 27 S 27.7 C 25.5 C 32nd Avenue & Pines Road S 23.5 C 17.7 B Madison Road & Thorpe Road U 11.0 B 9.5 A 32nd Avenue & SR 27 S 19.6 B 23.0 C 32nd Avenue & Evergreen Road U 10.6 B 17.7 C 32nd Avenue & Sullivan Road U 11.1 B 12.1 B In addition to assessing potential project effects on the capacity of critical intersections in the vicinity, WCE’s 2016 TIA also evaluated the extent to which traffic utilizes the Midilome East neighborhood as a cut-through route between East 32nd Avenue and South Madison Road, via South Woodland Drive and East 40th Avenue. For this cut-through analysis, WCE completed traffic counts during the AM and PM Peak hour on South Woodlawn Drive to identify total volumes and used video to identify vehicles that entered and exited the neighborhood without originating or stopping at a residence. The study found that there were five cut-through trips in the AM peak hour and seven cut-through trips in the PM peak hour. WCE has theorized that cut-through traffic was likely an attempt by drivers to avoid congestion at the intersection of East 32nd Avenue and South Pines Road. Spokane County has recognized the need for additional east-west connectivity in this area and as identified on the Arterial Road Plan (Figure 9) within the County’s Transportation Element of the Comprehensive Plan, a new arterial route is proposed within the East 40th Avenue alignment between South Pines Road and SR-27 and this improvement is identified for completion on the County’s six-year Transportation Improvement Program. Half-street improvements for East 40th Avenue have already been completed west of SR-27 for an approximately 1,060 lineal foot segment of the road constructed as a part of a new subdivision. It is anticipated that additional segments of the road will be Painted Hills Residential Development | Spokane Valley, Washington Page 56 Final Environmental Impact Statement completed between South Pines Road and SR-27 as properties along this alignment develop, if not constructed before by the county. When the county initiates completion of this segment of East 40th Avenue, the HOA will be required to cooperate with the County with the provision of right of way through the triangle pond property. It is expected that the completion of East 40th Avenue by the County and property owners adjacent to the triangle pond will improve regional mobility in a manner that will encourage drivers to use primary county arterials rather than use S. Woodlawn Drive in the Midilome East neighborhood. 3.3.2 Environmental Consequences 3.3.2.1 Alternative 1 – No Action Trip Generation Impacts As a part of the 2016 TIA, WCE evaluated traffic operations at the study intersections in the year 2025 without implementation of the Painted Hills PRD project. This 2025 no-build scenario reflects the anticipated conditions that would occur under Alternative 1. In order to approximate traffic volumes under Alternative 1, WCE assumed that regional traffic volumes would grow over the 10-year evaluation period (from 2015 to 2025) at a rate of 1.1 percent per year. In addition to this general 1.1 percent growth factor, the TIA also incorporated traffic volumes from other development projects that had not been built but had been approved by the City and Spokane County for development. These approved and vested projects, and their associated traffic volumes are identified in Table 3-4. Table 3-4: Background Projects and Vested AM & PM Trips (Table 4 of TIA) Background Project Remaining Lots/ units AM Peak. Hour Trips PM Peak Hour Trips Total In Out Total In Out Paxton Addition 13 lots 10 3 7 13 8 9 The Creek at Chester 44 lots 33 9 24 44 29 15 Pine Valley Ranch Apts. 132 units 69 14 55 90 59 31 Elk Ridge Heights 78 lots 59 15 44 79 51 28 Total Vested - 171 41 130 226 147 83 As noted in Table 3-5, acceptable LOS were projected for all study intersections in the year 2025 for Alternative 1, except the intersection of 16th Avenue and Pines Road. At this intersection, the southbound approach experienced delays that exceeded the City’s LOS threshold for the PM peak hour. However, it is anticipated that paired signalized intersections will be installed at this location that will improve conditions to an LOS C in this location. No other system deficiencies were identified under Alternative 1. Painted Hills Residential Development | Spokane Valley, Washington Page 57 Final Environmental Impact Statement Table 3-5: 2025 Levels of Service, without the Project, with the Background Projects (Table 7 of TIA) INTERSECTION (S) signalized (U) unsignalized AM Peak Hour PM Peak Hour Delay (sec) LOS Delay (sec) LOS 32nd Avenue & University Road S 12.2 B 11.9 B Dishman-Mica Road & University/Schafer Road S 16.4 B 17.2 B 32nd Avenue & Bowdish Road S 15.2 B 13.5 B Dishman-Mica Road & Bowdish Road S 12.8 B 11.8 B Dishman-Mica Road & Thorpe Road U 11.3 B 10.9 B 16th Avenue & Pines Road  Paired Signalized Intersections U (S) 26.2 (30.5) D (C) 66.4 (33.7) F (C) 16th Avenue & SR 27  Paired Signalized Intersections S 33.6 (42.3) C (D) 30.3 (28.4) C (C) 32nd Avenue & Pines Road S 27.0 C 21.9 C Madison Road & Thorpe Road U 12.1 B 9.9 A 32nd Avenue & SR 27 S 22.3 C 28.2 C 32nd Avenue & Evergreen Road U 11.2 B 23.6 C 32nd Avenue & Sullivan Road U 12.0 B 13.2 B In conjunction with the CUP-2020-0004 request for the commercial driving range, a trip generation and distribution letter were submitted that documented that the proposed driving range will generate approximately 219 average daily trips, with an average of nine PM peak hour trips per day. Because Condition 7 of the CUP approval for the driving range requires the closure of the driving range upon issuance of construction approvals associated with the PRD (SUB-2015-0001/PRD-2015-0001), the driving range trips would be eliminated from the system before any PRD-generated trips would occur. However, if the PRD were not implemented, it is assumed that the driving range trips would continue on the system. Construction-Related Project Impacts As no construction would occur under Alternative 1, there would be no construction-related traffic impacts that could result from this alternative. Safety Impacts As no action would occur under Alternative 1, there would be no safety-related traffic impacts that could result from this alternative. Painted Hills Residential Development | Spokane Valley, Washington Page 58 Final Environmental Impact Statement 3.3.2.2 Alternative 2a – Planned Residential Development High Infiltration Rate Trip Generation Impacts The TIA analyzes the ability of the study area intersections to meet adopted LOS standards in the year 2025 after incorporating the background growth rate, background projects, and the anticipated Painted Hills PRD project trips, including the conversion of the clubhouse into a 4,000 square feet (SF) restaurant facility. It is anticipated that Alternative 2a would generate new trip volumes as noted in Table 3-6, which is a copy of Table 14 from the TIA. It should be noted that, while the 4,000 SF restaurant trips were forecasted in the 2016 TIA, the restaurant use has now occupied the clubhouse structure and is in operation (WCE, 2016). Under Alternative 2a, new trips generated on the transportation system are shown in the Table 3-6. Table 3-6: Estimated Trip Generation – Alternative 2a Land Use Code (LUC) AM Peak Hour Trips PM Peak Hour Trips Vol. per LUC Directional Distribution Vol. per LUC Directional Distribution In Out In Out LUC #230 Townhouses (Cottage Style) (Table 6) 23 4 19 28 19 9 LUC #210 Single Family Residential (SFR) (Table 7) 155 39 116 201 127 74 LUC #210 SFR (Estate Lots) (Table 8) 32 8 24 42 26 16 LUC #220 Apartment (Table 9) 117 23 94 138 90 48 LUC #220 Apartment (mixed use) (Table 10) 27 5 22 32 20 12 LUC #820 Shopping Center (Table 11) 13 8 5 40 20 20 LUC #820 Shopping Center (Table 12) 9 6 3 34 16 18 LUC #931 Quality Restaurant (Table 13) 4 2 2 30 20 10 Total 380 95 285 545 338 207 Average Daily Trip Ends (ADT) Land Use Code (LUC) Rate ADT LUC #230 Townhouses (Cottage Style) (Table 6) - 303 LUC #210 Single Family Residential (Table 7) - 1,962 LUC #210 SFR (Estate Lots) (Table 8) - 400 LUC #220 Apartment (Table 9) - 1,517 LUC #220 Apartment (mixed use) (Table 10) - 346 LUC #820 Shopping Center (Table 11) - 573 LUC #820 Shopping Center (Table 12) 385 LUC #931 Quality Restaurant (Table 13) 360 Total - 5,846 Painted Hills Residential Development | Spokane Valley, Washington Page 59 Final Environmental Impact Statement Due to the mixed-use nature of Alternative 2a, a trip internalization factor is applied to the trip generation rates of the residential uses that would occur under this alternative. That internalization factor applies a reduction or discount factor on the typical generation rate for the residential uses to address the fact that some of the retail and service needs of the residents of the Painted Hills PRD project will be satisfied by the 22,400 SF of commercial space located within the project. This internalization factor varies by residential use type but ranges between approximately 2.4 and 3.0 percent of the PM peak hour trip generation for the residential uses. Based on these assumptions and application of the ITE manual, Alternative 2 is estimated to generate vehicular trips consistent with the figures represented in Table 3-6. As shown above, Alternative 2a is anticipated to generate 380 new AM peak hour trips, with 95 new trips entering the Painted Hills site, and 285 new trips exiting the site via the eight access opportunities previously noted. In the PM peak hour, the Painted Hills PRD project is anticipated to generate 545 new trips, with 338 new trips entering the site, and 207 new trips existing the site. When adding the trips generated from Alternative 2a to the local road system, considering background traffic volumes and vested project trips, the TIA determined that all intersections can meet City-adopted LOS standards, except for the intersection of 16th Avenue and Pines Road, which also failed to meet LOS standards in Alternative 1—No Build. Alternative 2a extends the delay experienced at this intersection from 66.4 seconds during the PM peak hour under background conditions to 99.2 seconds. These results are noted in Table 3-7. Therefore, the addition of trips from Alternative 2a does not create any new LOS failures but does result in additional delays at the intersection of 16th Avenue and Pines Road. Table 3-7: Year 2025 Levels of Service, with the Project, with the Background Projects (Table 19 of the TIA) INTERSECTION (S) signalized (U) unsignalized AM Peak Hour PM Peak Hour Delay (sec) LOS Delay (sec) LOS 32nd Avenue & University Road S 12.4 B 12.4 B Dishman-Mica Road & University/Schafer Road S 16.9 B 18.3 B 32nd Avenue & Bowdish Road S 15.6 B 14.7 B Dishman-Mica Road & Bowdish Road S 15.7 B 13.3 B Dishman-Mica Road & Apt. Access U 13.2 B 10.4 B Dishman-Mica Road & Sundown Drive U 12.6 B 10.8 B Dishman- Mica Road & S. Comm. Access U 11.5 B 11.3 B Dishman-Mica Road & Thorpe Road U 11.9 B 11.9 B Thorpe Road & Comm. Access U 9.0 A 9.1 A 16th Avenue & Pines Road • Paired Signalized Intersections U (S) 27.3 (31.1) D (C) 99.2 (34.8) F (C) 16th Avenue & SR 27 • Paired Signalized Intersections S 35.9 (44.6) D (D) 31.3 (28.6) C (C) Painted Hills Residential Development | Spokane Valley, Washington Page 60 Final Environmental Impact Statement 32nd Avenue & Pines Road • NB Right Turn S 32.3 (27.6) C (C) 26.0 (24.7) C (C) Madison Road & Painted Hills Avenue U 11.1 B 10.8 B Madison Road & 41' Avenue U 10.7 B 10.5 B Madison Road & 43rd Avenue U 10.5 B 10.2 B Madison Road & 44th Avenue U 9.7 A 9.6 A Madison Road & Thorpe Road U 12.4 B 10.4 B 32nd Avenue & SR 27 S 23.2 C 29.8 C 32nd Avenue & Evergreen Road U 11.6 B 26.1 D 32nd Avenue & Sullivan Road U 12.3 B 13.5 B In addition to the LOS failure at the intersection of 16th and Pines Road, the TIA found that there are three instances in the 2025 forecast in which the stacking queues at intersections exceed allowable City standards. These are described in detail on Page 54 of the 2016 TIA and are as follows: 16th Avenue & SR 27  The eastbound through approach is expected to go from a queue length of 586 feet to 645 feet, an increase of 59 feet. This reported queue exceeds the available space by 526 feet.  The westbound through approach is expected to go from a queue length of 310 feet to 319 feet, an increase of 9 feet. This reported queue exceeds the available space by 149 feet. 32nd Avenue & Pines Road  The eastbound through approach is expected to go from a queue length of 562 feet to 708 feet, an increase of 146 feet. This reported queue exceeds the available space by 218 feet. 32nd Avenue & SR 27  The westbound through approach is expected to go from a queue length of 470 feet to 497 feet, an increase of 27 feet. This reported queue exceeds the available space by 305 feet.  The westbound left turn approach is expected to go from a queue length of 246 feet to 238 feet, a decrease of 8 feet. This reported queue exceeds the available space by 88 feet. Extension of East 40th Avenue  Spokane County identifies the extension of East 40th Avenue between South Pines Road and Highway 27 as a future urban arterial route in Figure 6 of the Comprehensive Plan’s Transportation Element and “Program Item 36” in the County’s 2023-2028 Six-Year Transportation Improvement Plan. The extension of 40th is expected to dissuade cut-through traffic by providing a more direct east/west route with less traffic control measures comparative to the neighborhood. Section 3.3.2.2 of the FEIS has been updated to address extension of East 40th Avenue. Painted Hills Residential Development | Spokane Valley, Washington Page 61 Final Environmental Impact Statement  The PRD applicant will be purchasing the triangle pond property which the HOA will ultimately own and manage. When the county initiates right of way acquisition for East 40th Avenue the HOA will participate in the necessary dedication of right of way to engage the completion of the improvement between SR-27 and South Pines Road. As noted on Page 72 of the TIA, the study also considered traffic operations in the year 2030, which was considered “buildout plus 5 years” at the time of the study. The TIA included the following findings regarding traffic operations in 2030 resulting from the Painted Hills PRD project, including background growth and vested projects.  There is a LOS deficiency identified at the intersection of 16th Avenue & Pines Road, as the southbound approach is estimated to have 133.7 seconds of average delay.  The LOS deficiency identified at the intersection of 16th Avenue & Pines Road, originally caused by the background trips, and worsened by the Painted Hills PRD project, can be brought back to an acceptable LOS by signalizing the intersection and pairing the signal timing with the signal at the intersection of 16th Avenue & SR 27.  There are five future queue deficiencies at three intersections with two of those intersections operating at acceptable LOS. These deficiencies were the result of the background growth rate and the background projects as identified within this study and are only incrementally worsened or kept the same by this project. A review of the City of Spokane Valley Transportation Improvement Plan (TIP), shows that there are no public improvement projects identified to mitigate the discrepancies at the following intersections and movements: o 16th Avenue & SR 27, Eastbound Thru, Westbound Thru o 32nd Avenue & Pines Road, Eastbound Thru  32nd Avenue & SR 27, WB Thru, Westbound Left Turn Construction-Related Project Impacts It is anticipated that the Painted Hills PRD project will result in construction-related traffic associated with site grading and site development activities. These impacts are discussed in memoranda prepared by WCE dated November 13, 2018; and February 15, 2021. As noted in the memos, it is anticipated that mass grading activities for Alternative 2a will require the placement and compaction of 328,289 cubic yards (CY) of material. This material will need to be imported to the site as “loose” dirt which will require compaction on the site. WCE estimates that, due to a 15 percent shrink/swell factor, the required loose fill import volume is approximately 377,532 CY. It is assumed that site grading will occur over an approximately four-year period and that the material will be delivered via dump trucks that carry a volume of approximately 30 CY. Based on these assumptions, it is estimated that approximately 12,584 dump trucks will be required to fill the site over a four-year period. This equates to 25,168 truck trips to and from the site. Below is a more detailed analysis of potential impacts related to importing of the fill material. Painted Hills Residential Development | Spokane Valley, Washington Page 62 Final Environmental Impact Statement Truck Volumes, Traffic Operations and Phasing Dump truck trips to the site could occur at any time throughout the year during the initial mass grading period of the project, which is assumed to occur over an approximately four year period at the onset of the project.4 During this period, fill material could be accepted year round and stockpiled when/as necessary Assuming a Monday to Friday work schedule and five working days per week spread over 260 working days per year, if truck trips were to occur consistently over this four-year period approximately 12 trucks per day would arrive at the site or approximately 24 truck trips per day. If truck trips to the site were significantly curtailed or limited during the cold weather months, then a more conservative annual work window of between April 1st and November 15th could be considered when estimating truck volumes. In this scenario, an approximately 31-week annual mass grading period could occur with approximately 155 business days. In that scenario, it is estimated that the project fill activities will result in approximately 20.3 trucks per day/40.6 truck trips per day during the initial four-year annual work window. Consequently, it can be reasonably deducted that truck volumes over the initial fill period for the project would be between approximately 11.24 and 22.3 trucks per day and between approximately 22.47 and 40.59 truck trips per day. The haul route for these dump trucks will be via Dishman-Mica Road, a Principal Arterial that experiences a total Average Daily Traffic (ADT) of approximately 22,700 trips near Appleway Avenue and 4,800 ADT near Thorpe Road. Therefore, the dump truck-related trips are estimated to represent less than one percent of the ADT of this facility on average. Dishman-Mica Road has been designated by the City as a Principal Arterial. If the mass grading schedule for the project were prolonged beyond the estimated four-year window, the approximate number of truck trips per day would decrease respective to the mass grading time period. It is anticipated that truck deliveries would occur between 7 AM and 6 PM, Monday through Friday, consistent with the City’s Truck Haul Plan requirements. The increased truck traffic would impact non-construction related users of the local roadway system. Potential impacts to local users would include traffic delays due to additional truck traffic on the roads, and inconvenience and potential danger caused by fugitive dust and spilled fill materials on the roadways. In addition, additional traffic could result in damage to existing roadway infrastructure including pavement surfaces, signs, and guardrails. Per the City of Spokane Valley Haul plan requirements item #5, any damage to the public roadway or roadway elements is the responsibility of the contractor. Safety Truck trips will enter and exit the Painted Hills site through controlled accesses from Dishman-Mica Road. These accesses will be designed with stabilized entrances to reduce the potential for dirt and construction debris to occur on the road that could pose a hazard to motorists and bicyclists. Access points on Dishman- Mica Road will be designed to ensure safe sight distances per the American Association of State Highway and Transportation Officials (AASHTO) and local standards to ensure that turning movements into and out of the site will have adequate vision clearance. 4 The first year improvements will include the establishment of stormwater / floodwater conveyance and management facilities to ensure that stormwater and floodwater are managed and recharge on site. The four- year initial rough grading period is different than the full buildout period of the project, which is estimated occur over a period of 10-years, including the final construction of buildings on the site. Painted Hills Residential Development | Spokane Valley, Washington Page 63 Final Environmental Impact Statement The additional truck traffic could pose potential safety risks to local users of the roadway system due to potential delays caused by trucks waiting to turn into the site and turning movements into and out of the site. A dedicated two-way left turn lane on Dishman-Mica Road and a northbound right-turn lane would be constructed as well to provide vehicular refuges for vehicles turning into the site. To mitigate for any potential safety impacts caused by vehicular movements into and out of the site at the Dishman-Mica Road access, it is recommended that these new vehicular lanes are constructed prior to the initiation of mass grading activities on the site. The provision of these turn lanes at the initiation of the project and prior to mass grading activities will help to direct trucks off of the primary through travel lanes to improve motorist and bicycle safety. The Painted Hills site boundary along South Madison Road ends approximately 300 feet south of the existing sidewalk on South Madison Road at 40th Avenue, leaving a potential pedestrian gap in that location. The applicant intends to address this connection by extending a paved pedestrian path within the South Madison Road right of way to ensure a continuous pedestrian connection on the west side of South Madison Road between East Thorpe and East 40th Avenue. Public comments received from neighbors in the Midilome neighborhood northeast of the site have focused on existing speeding and vehicles that cut-through the neighborhood as a short cut between Madison Road and East 32nd Avenue. This issue was studied by WCE in their 2016 traffic study, which found that there were five cut-through trips in the AM peak hour and seven cut-through trips in the PM peak hour on South Woodlawn Drive. WCE theorizes that the cut-through traffic is likely an attempt by drivers to avoid congestion at the intersection of E. 32nd Avenue and S. Pines Road. The TIA revealed that this intersection would have a queuing deficiency in the Eastbound right turn movement in the future under the No Action scenario (Alternative 1). The failure was based upon existing and projected background traffic and not by Painted Hills-generated traffic. In Alternatives 2a and 2b vehicles originating from the Painted Hills PRD are not expected to significantly increase traffic flow along S. Woodlawn Drive as a dedicated right turn lane has been recommended for completion with the project and will improve LOS at the intersection for north bound traffic. Reference to the Midilome East study can be located in the TIA, under the Appendix titled “Woodlawn Drive Tube Counts” on page 364. Further, future completion of East 40th Avenue, a proposed county arterial in the Transportation Element of the Spokane County Comprehensive Plan will provide additional east-west connectivity in the region and will encourage motorists to use primary arterials to travel between South Pines Road and SR-27, rather travel through the Midilome East neighborhood via South Woodlawn Drive. It should also be noted the Spokane County Arterial Road Plan identifies that a new arterial will be constructed in the alignment of East 40th Avenue between Madison Road and SR-27. When this road is completed, it is expected that a reduction in any cut-through traffic experienced in the Midilome neighborhood would occur as the new arterial will provide a more efficient path for east-west traffic in the project vicinity. Public Comments received from neighbors have focused on pedestrian and cyclist safety concerns posed both during construction and upon full build out. The issues identified in public comments include general vehicular traffic volume concerns and concerns regarding speeding on South Pines/South Madison, Woodland Drive in the Midilome East neighborhood, Thorpe Road, and East 32nd Avenue. The issue of vehicular speed was not studied in WCE’s 2016 traffic study as speeds are controlled by the City and County and considered a local law enforcement issue rather than a transportation concurrency issue. Public comments received that identified general safety concerns noted that additional traffic resulting from the Painted Hills PRD would pose a safety concern for pedestrians, specifically school-age children walking to Horizon Middle School and Chester Elementary School. As noted in earlier paragraphs of this section, the applicant intends to provide a continuous pedestrian walkway around and through the entire Painted Hills PRD site and a crosswalk at the intersection of East 40th Avenue and South Pines Road/South Madison Road that will include a flashing beacon warning system to alert motorists to stop for pedestrians crossing the street. The addition of the cross walk adjacent to Horizon Middle School will encourage pedestrian safety and will supplement other potential measures, such as school zone speed limits, school zone signage, and cross walk attendants. It is anticipated a condition of approval would be imposed on the PRD by the City that stipulates the installation of the crossing and flashing beacon. Painted Hills Residential Development | Spokane Valley, Washington Page 64 Final Environmental Impact Statement 3.3.2.3 Alternative 2b – Planned Residential Development—Low Infiltration Scenario Trip Generation Impacts The total traffic generation resulting from the land uses of Alternative 2b is nearly identical to Alternative 2a, with a slight overall decrease in the number of trips. Table 3-8 illustrates the land use differences between Alternative 2a and Alternative 2b. As a result, the trip generation impacts for Alternative 2b are assumed to be identical to Alternative 2a. Table 3-8: Alternative 2A and 2B ADT Comparison – PM Peak Hour Trips5 Land Use Alternative 2a Alternative 2b Net Difference Units / ksf PM Peak Hr Trips Units / ksf PM Peak Hr Trips Cottages 52 52 0 0 -52 SFR – Standard 206 201 224 217 +16 SFR – Estate 42 42 48 48 +6 MFR 228 138 273 174 +36 MFR–Mixed Use 52 32 52 32 0 Commercial N 13.4 26 13.4 26 0 Commercial S 9 34 9 34 0 Commercial S 4 30 4 30 0 Total 555 531 -24 Construction Related Impacts Alternative 2b is anticipated to result in construction-related traffic associated with site grading and a substantial amount of fill material to bring development areas above the 100-year base flood elevation. These impacts are also discussed in a memorandum prepared by WCE dated November 13, 2018; and February 15, 2021. As noted in the memorandum, like Alternative 2a, Alternative 2b would require a substantial amount of compacted fill material to bring development areas above the 100-year base flood elevation, however, Alternative 2b would generate significantly fewer construction-related trips than Alternative 2a. Alternative 2b would require less imported compacted fill than Alternative 2a because material excavated to create the larger Alternative 2b infiltration pond (due to greater floodplain storage volume required on the site) would be used elsewhere instead of importing fill. Specifically, Alternative 2b would require approximately 104,630 CY of imported fill material on the site compared to 328,289 CY of imported fill material for Alternative 2a. Because the total net fill volume for Alternative 2b is only approximately 31 percent of the total net fill volume anticipated with Alternative 2a, it is estimated that approximately 7,846 total dump truck round trips will occur. As with Alternative 2a, the haul route truck trips under Alternative 2b will be via Dishman-Mica Road, designated by the City as a Principal Arterial. 5 Note: All trip generation rates included in this table are from the Institute of Transportation Engineers (ITE) Trip Generation Manual, 9th edition, the manual in place on February 23, 2017, when the traffic concurrency approval for the PRD Alternative 2a was issued by the City. The ITE 10th edition has reduced the trip generation rate for multi-family residential from 0.65 to 0.45 PM peak hour trips per unit. This is the only ITE manual change for planned uses within the PRD. Painted Hills Residential Development | Spokane Valley, Washington Page 65 Final Environmental Impact Statement Below is a more detailed analysis of potential impacts related to importing of the fill material. Truck Volumes, Traffic Operations and Phasing Like Alternative 2a, dump truck trips to the site could occur at any time throughout the year during the initial mass grading period of the project, which is assumed to occur over an approximately four-year period at the onset of the project. During this period, fill material could be accepted year-round and stockpiled when necessary. However, as compared to Alternative 2a, the number of truck trips is less. If truck trips were to occur consistently during workdays over this four-year period, under Alternative 2b, approximately 3.9 trucks per day would arrive at the site or approximately 7.8 truck round trips per day, assuming 260 workdays per year. If truck trips to the site were significantly curtailed or limited during the cold weather months, then a more conservative annual work window of between April 1 to November 15th time frame could be considered when estimating truck volumes. In this scenario, an approximately 31-week annual mass grading period could occur with approximately 155 workdays. In this scenario, the estimated number of trips per day in each of the first four years of development is approximately 6.3 trucks per day or 12.6 truck round trips per day. As with Alternative 2a, the haul route for these dump trucks will be via Dishman-Mica Road, a Principal Arterial that experiences a total ADT of approximately 22,700 trips near Appleway Avenue and 4,800 ADT near Thorpe Road. Therefore, the dump truck-related trips are estimated to be less than one percent of the ADT of this facility on average. If the mass grading schedule for the project were prolonged beyond the estimated four-year window, the approximate number of truck trips per day would decrease respective to the mass grading time period. As with Alternative 2a, truck trips would occur generally between 7 AM to 6 PM, consistent with the City of Spokane Valley truck haul plan requirements. Safety As with Alternative 2a, truck trips will enter and exit the Painted Hills site through controlled accesses from Dishman-Mica Road. These accesses will be designed with stabilized rock entrances to reduce the potential for dirt and construction debris to occur on the road that could pose as a hazard to motorists, bicyclists, and pedestrians. Access points on Dishman-Mica Road will be designed to ensure safe sight distances per the AASHTO and local standards to ensure that turning movements into and out of the site will have adequate vision clearance. The additional truck traffic could pose potential safety risks to local users of the roadway system due to potential delays caused by trucks waiting to turn into the site and turning movements into and out of the site. A dedicated two-way left turn lane on Dishman-Mica Road and a northbound right-turn lane would be constructed as well to provide vehicular refuges for vehicles turning into the site. To mitigate for any potential safety impacts caused by vehicular movements into and out of the site at the Dishman-Mica Road access, it is recommended that these new vehicular lanes are constructed prior to the initiation of mass grading activities on the site. Public comments received from neighbors in the Midilome neighborhood northeast of the site have focused on existing speeding and vehicles that cut-through the neighborhood as a short cut between Madison Road and East 32nd Avenue. This issue was studied by WCE in their 2016 traffic study, which found that there were five cut-through trips in the AM peak hour and seven cut-through trips in the PM peak hour on South Woodlawn Drive. WCE theorizes that the cut-through traffic is likely an attempt by drivers to avoid congestion at the intersection of E. 32nd Avenue and S. Pines Road. The TIA revealed that this intersection would have a queuing deficiency in the Eastbound right turn movement in the future under the No Action scenario (Alternative 1). Painted Hills Residential Development | Spokane Valley, Washington Page 66 Final Environmental Impact Statement The failure was based upon existing and projected background traffic and not by Painted Hills-generated traffic. In Alternatives 2a and 2b, vehicles originating from the Painted Hills PRD are not expected to significantly increase traffic flow along S. Woodlawn Drive as a dedicated right turn lane has been recommended for completion with the project at S Pines Road and E 32nd Avenue that will improve LOS at the intersection for north bound traffic and therefore encourage vehicles to remain on the local arterial system rather than cut through the Midilome East neighborhood. Reference to the Midilome East study can be located in the TIA, under the Appendix titled “Woodlawn Drive Tube Counts” on page 364. It should also be noted the Spokane County Arterial Road Plan identifies that a new arterial will be constructed in the alignment of East 40th Avenue between Madison Road and SR-27. When this road is completed, a significant reduction of any cut-through traffic experienced in the Midilome neighborhood is likely to occur as the new arterial will provide a more efficient path for east-west traffic in the project vicinity. As with Alternative 2a, pedestrian circulation around the perimeter of the site will be provided by a continuous pedestrian walkway, designed consistent with the City of Spokane development standards. Traffic design techniques and traffic calming measures to protect pedestrians and slow traffic are both addressed through the crosswalk, which the applicant plans to construct at the intersection of East 40th Avenue and South Pines Road/South Madison Road. 3.3.3 Mitigation Measures Alternative 1 No mitigation would be required under Alternative 1, as no action would occur on the site. However, it is assumed that existing background conditions on the site would result in a LOS failure at 16th Avenue and Pines Road that would require the city or others to signalize the intersection and pair the signal timing with the signal at 16th Avenue and SR 27. Alternative 2a Consistent with the mitigation measures identified in the TIA and those listed in the City’s Traffic Concurrency Conditions of Approval for PRD-2015-0001, it is anticipated that the following mitigation measures would be implemented in conjunction with the construction of Alternative 2a. A copy of the Certificate of Transportation Concurrency is included with the FEIS as Appendix L.  All improvements will conform to City of Spokane Valley Standards.  The project may have up to two new commercial driveway approaches on Dishman-Mica Road along the frontage of the project. Conditions 2a. and 2b. below are based on the current design of the Project and may be subject to review and revision if conditions change in the future. o The northernmost commercial driveway approach shall access the apartments only and shall be restricted to right-in/right-out by means of a raised median along Dishman-Mica Road or via a pork chop island within the driveway. The design of the median or pork chop shall be approved by the City. o The southernmost commercial driveway approach shall access the northern commercial site only along Dishman-Mica and may be a full movement driveway with a two-way left-turn lane along Dishman-Mica for left-turn access.  Frontage improvements are required for Madison Road, Thorpe Road, and Dishman-Mica Road prior to the final approval of the first phase of the Project. Dishman-Mica Road is designated as minor arterial. Thorpe Road and Madison Road are designated as collector arterials. Painted Hills Residential Development | Spokane Valley, Washington Page 67 Final Environmental Impact Statement  The entire Project shall be accessed by one new public local access street that intersects Dishman- Mica Road and two new public local access streets that intersect Madison Road. In addition, two new gated private streets are permitted on Madison Road.  The Project shall construct southbound left-turn lanes on a) Dishman-Mica Road at the intersection with the new public local access street and at b) the intersection of Dishman-Mica Road and Thorpe Road concurrently with the construction of the new public local access street. The two southbound left-turn lanes shall provide a minimum of 150 feet of queue storage and shall have the required gap and taper lengths per WSDOT standards.  The project will construct a new flashing beacon and cross walk at the intersection of East 40th Avenue and South Madison/South Pines to facilitate safe pedestrian and cyclist access adjacent Horizon Middle School. At any time, the City may make modifications to this intersection if it determines that such modifications are necessary for the health, safety, and welfare of the traveling public.  The HOA will cooperate with the County to ensure right of way is provided at the triangle pond if/as necessary for the completion NE 40th Avenue between SR-27 and South Pines Road.  The existing commercial site located on the southwest corner of the Project site will continue to be accessed by a single full movement approach on Thorpe Road. At any time, the City may make modifications to this intersection if it determines that such modifications are necessary for the health, safety, and welfare of the traveling public.  The TIA identified the need for improvements at the 32nd/Pines intersection. The TIA acknowledges that the Project contributes to the need for improvements at this intersection. As identified, the Developer shall construct a northbound right-turn lane on Pines Road prior to the City’s issuance of a certificate of occupancy for the 400th unit of the Project. The storage length for the dedicated right- turn only lane shall be determined at the time of development. The Developer shall furnish the City an intersection plan substantially similar to that required by WSDOT Standards for final approval prior to construction.  The TIA identified the need for improvements at the 16th Avenue/Pines/SR 27 intersections. The TIA acknowledges that the Project contributes to the need for improvements at these intersections. As identified, additional traffic capacity is needed which requires a new southbound right-turn only lane on Pines Road and a new traffic signal at 16th and Pines. The Developer shall furnish these improvements prior to the City’s issuance of a certificate of occupancy for the 200th unit. The Developer shall furnish the City an intersection plan similar to that required by WSDOT and Traffic Signal Plans for final approval prior to construction.  The City may determine to seek funding and/or complete traffic improvements at the Pines/32nd or the 16th/Pines/SR-27 intersections. If the City determines to pursue funding or complete improvements prior to the Developer completing the improvements identified in Conditions 7 and 8 above, in compliance with RCW 82.020.20, the Developer shall enter into a voluntary mitigation agreement with a proportionate contribution toward the City’s improvements. It should be noted that, since the time of the issuance of the Traffic Concurrency Conditions of Approval noted above, the local agencies and WSDOT have established that the preferred improvement to address capacity issues at the 16th Avenue/Pines/SR 27 intersection is a five-leg intersection. It is anticipated a condition of approval would be imposed on the PRD by the City that stipulates pro-rata contribution towards this improvement in lieu of completing a capacity improvement. Painted Hills Residential Development | Spokane Valley, Washington Page 68 Final Environmental Impact Statement In addition to the measures noted above, the following additional mitigation measures will be required with project implementation.  Prior to the initiation of mass-grading activities associated with the project, the applicant will install a two-way left turn lane on Dishman-Mica Road and a right-turn northbound lane on Dishman-Mica Road at the proposed new entry road into the PRD.  Bicycle and pedestrian facilities per the City of Spokane Valley Bicycle and Pedestrian Master Plan will be completed along the site frontages, including a continuous five-foot-wide pedestrian walkway around and throughout the Painted Hills PRD site.  A final haul route plan approved by the City will be developed and managed to ensure that truck trips to and from the site during construction use Dishman-Mica Road for site access over the duration of site construction. This plan should include a section devoted to pre- and post-construction inspections of the facility to determine any pavement failures that can be attributed to the construction trips. A draft of this Truck Haul Memorandum is provided as Appendix G.  Stabilized construction entrances will be provided to minimize the potential for dirt and debris to be carried onto the road by exiting construction vehicles.  The applicant shall install an approximately 300-foot-long paved pedestrian connection on the west side of South Madison Road adjacent to the approximately 2-acre Water District #16 property. This connection will ensure a continuous pedestrian walkway on the west side of South Madison Road between East Thorpe Road and East 40th Avenue.  After completion of the initial grading and the issuance of the letter of map revision (LOMR) and issuance of the first phase Final Plat and prior to the issuance of the building permit that would exceed 100 cumulative trips, the Applicant will complete an update to the approved Traffic Impact Analysis (TIA) based on a revised build-out year and horizon year. The TIA update shall include updated turning movement counts and an update to the trips from the vested projects identified in the approved TIA as well as updated mitigation to account for changing construction costs and mitigation projects.  The approved TIA identifies a build-out year of 2025 after 7-8 years of phased construction and a planning horizon year of 2030. However, as described in this EIS, the time period for importing fill and constructing the project is at least 14 years (four years for importing fill and ten years for phased construction of the project). The traffic review should be updated to account for the inconsistency in the EIS between the original identified build-out year of 2025 and the time period estimated for project completion. Such update should include an additional horizon year analysis as determined by fill and construction parameters as well as FEMA coordination, which is estimated at 2042 or beyond. Alternative 2b It is anticipated that the mitigation measures required with the implementation of Alternative 2b would be the same as those listed in Alternative 2a above. 3.3.4 Cumulative Effects Vested and unbuilt projects were considered in the background traffic volumes that were incorporated into the TIA, thereby addressing the potential cumulative transportation effects of the action alternatives when concerned with other on-going developments. The other regional projects that were considered in the TIA and their associated traffic volumes are noted in Table 3-9. Painted Hills Residential Development | Spokane Valley, Washington Page 69 Final Environmental Impact Statement Table 3-9: Background Projects and Vested AM & PM Trips Background Project Remaining Lots/ units AM Peak. Hour Trips PM Peak Hour Trips Total In Out Total In Out Paxton Addition 13 lots 10 3 7 13 8 9 The Creek at Chester 44 lots 33 9 24 44 29 15 Pine Valley Ranch Apts. 132 units 69 14 55 90 59 31 Elk Ridge Heights 78 lots 59 15 44 79 51 28 Total Vested - 171 41 130 226 147 83 In a similar fashion, applicants for new development proposed after the City issued its certificate of concurrency for the Painted Hills PRD, are required to consider Painted Hills-generated trips as background volumes in their traffic analysis and City concurrency requests. This system ensures that in instances such as the Painted Hills project, in which a delay in application processing occurs, that continuous re-evaluations of traffic impacts are not required. 3.4 ENVIRONMENTAL ELEMENTS NOT ANALYZED IN DETAIL 3.4.1 Air Quality 3.4.1.1 Affected Environment Air quality can directly affect human health with cardiovascular and other health complications resulting from exposure to air pollutants. These can include human-generated pollutants (carbon monoxide, carbon dioxide[CO2], and lead, from automobiles and industrial sources); naturally generated pollutants (fine particulate matter in forest fire smoke), or a combination of both. Dust and non-toxic nuisance odors are also a component of air quality. The U.S. Environmental Protection Agency (EPA) sets National Ambient Air Quality Standards (NAAQS) for six criteria pollutants known to impact human health. The six criteria pollutants include carbon monoxide (CO), particulate matter (PM), ozone (O3), sulfur dioxide (SO2), lead (Pb), and nitrogen oxide (NOx). In the past, Spokane has been in nonattainment for both CO and Particulate Matter (PM10). In the Spokane region currently, there are two pollutants of primary concern, fine particulate matter (PM2.5) and ground-level ozone6. While industry contributes about 20 percent of the PM2.5 and ground-level ozone air pollution, most of the pollution in the Spokane area results from transportation (vehicle emissions) and home heating. Ground-level ozone is not emitted directly into the air like other pollutants but is produced when NOx formed by combustion processes, and volatile organic compounds (VOCs) from many sources, combine. These ozone- producing pollutants come from local sources, such as cars, trucks, industrial boilers, power plants, paints, solvents, and other commercial and consumer products. According to the SRCAA, during the winter months wood heating is the largest source of fine particle pollution (SRCAA 2019). Stable weather patterns typical of the winter in Spokane Valley trap smoke near the ground, intensifying the problem. SRCAA may restrict outdoor burning during periods of poor air quality. In addition, local fire officials issue outdoor burn restrictions during fire safety season. 6 https://www.spokanecleanair.org/air-quality Painted Hills Residential Development | Spokane Valley, Washington Page 70 Final Environmental Impact Statement Air quality in the Spokane region generally becomes worse during the winter heating season due to the presence of fine particles from wood fires and during the hot, summer months in which ozone levels increase and (in recent years) regional forest fires occur. The Spokane area is not currently in non-attainment for ozone, PM2.5 or PM10; however, over the past 10 years ozone concentrations have approached non-attainment levels7. Spokane Clean Air began monitoring for PM2.5 in 1999, shortly after the PM2.5 health-based standard was established by EPA8. The health-based standard for PM2.5 has been exceeded during the winter months due to wood stove smoke in 9 of the past 19 years, including 2013, 2014, 2015, and 2017. The health-based standard for PM2.5 has been exceeded in July, August, and/or September due to forest fire smoke in 2014, 2015, 2017 (16 days), and 2018 (13 days) (SRCAA, 2017, 2019). In recognition of the effect of wood heating on air quality, Washington State has several laws addressing wood stoves including:  RCW 70.94.450, which establishes the policy of the state to control, reduce, and prevent air pollution caused by wood stove emissions; encourages Ecology to educate the public about the effects of wood stove emissions and other heating alternatives; and promotes the desirability of achieving better emission performance and heating efficiency from wood stoves.  RCW 70.94.455, which establishes standards for solid fuel burning devices and provides for the state building code to require an adequate source of heat other than wood stoves in all new and substantially remodeled residential and commercial construction.  RCW 70.94.473, which provides that, during an air pollution episode, alternatives to wood burning will be used in buildings with alternative sources of heat, and for those without alternatives, only certified wood stoves can be used. The City of Spokane Valley Municipal Code (Section 7.05.040 Nuisances Prohibited) requires the control of dust that could potentially cause a nuisance to City residents. Under the current vegetated, undeveloped conditions, minimal air pollutants are generated from the site. 3.4.1.2 Environmental Consequences 3.4.1.2.1 Alternative 1 – No Action Under Alternative 1, no changes to current air quality conditions are anticipated. The existing on-site vegetation would continue to function as a carbon “sink” rather than a source of atmospheric carbon. 3.4.1.2.2 Alternative 2a – Planned Residential Development—High Infiltration Under Alternative 2a, impacts to air quality would occur both during construction and during the operational lifetime of the project following construction. 7 https://www.spokanecleanair.org/documents/our_air/Ozone%20Trends%20Chart%20Jun%202017.jpg 8 The PM2.5 health-based standard is 35 micrograms per cubic meter of air (equivalent to 100 on the AQI) averaged over 24 hours, midnight to midnight. Prior to 1999, monitoring was done for smoke and dust particles combined (PM10- Particulate Matter 10 microns in diameter and smaller). Particulate matter (PM) has been measured by Spokane Clean Air since health-based air quality standards were established in 1971. The first standard was for Total Suspended Particulates, then revised in 1987 to Particulate Matter 10 microns and smaller (PM10). In 1997, EPA established an additional standard for Fine Particles (PM2.5). Painted Hills Residential Development | Spokane Valley, Washington Page 71 Final Environmental Impact Statement During construction, there would be tailpipe emissions from on-site construction equipment, and construction- related on-road vehicles including dump trucks, delivery trucks, and the personal vehicles belonging to construction workers. These tailpipe emissions will add VOCs, NOx, CO, CO2, and ground-level ozone to the air. During construction, some fugitive dust could be expected, although wind-erosion control prevention measures will be implemented to minimize these effects. In addition, some construction elements, such as asphalt paving operations may cause odors detectible to some people away from the project site. The effect of such odors would be short-term. Once the project has been constructed, the additional approximately 300 single family residential units, 280 multi-family units, and 26,400 SF of commercial use would generate air emissions that could include carbon dioxide, CO, NOx, and VOCs. Sources of these emissions could include natural gas and electricity-powered home appliances and space-heating systems, gasoline or electricity-powered yard maintenance equipment, gasoline or electricity-powered vehicles generated by the project. Additionally, wood stoves, if used within the project site, could also be a source of fine particulate (PM2.5) emissions. It is unlikely these emissions would cause ambient concentrations to exceed the NAAQS for NOx, CO, SO2, and Pb because historically these pollutants have not approached non-attainment levels in the Spokane area. Emissions associated with the project could potentially result in ozone and PM 2.5 concentrations that exceed NAAQS because the area has had concentrations of ozone that approach non-attainment concentrations for the past 10 years and has exceeded the health-based standard for PM 2.5 for 9 of the past 19 years, including 2017 and 2018. The emissions associated with a residential development would be consistent with the planned intent of the project site, which is designated for residential development by the City and for urban development within the Spokane County UGA. 3.4.1.2.3 Alternative 2b – Planned Residential Development—Low Infiltration Impacts to air quality under Alternative 2b will be similar to those described for Alternative 2a with the following exceptions:  Alternative 2b provides 18 more single-family residences than Alternative 2a, and the additional single-family residences may result in the production of slightly more fine particulates from wood burning stoves than under Alternative 2a.  Construction-related impacts to air quality will likely be less with Alternative 2b due to the reduced amount of imported fill material required and the fewer number of truck trips to and from the site. 3.4.1.3 Mitigation Measures Construction: During construction, the following best management practices will be followed to ensure that air quality effects are minimized to the extent possible:  Well-maintained construction equipment and trucks will be used to reduce emissions; vehicles and equipment will be fitted with emission-controlling components such as air filters and catalytic convertors.  Prolonged periods of idling vehicles and other engine-powered equipment will be avoided.  During construction, areas of exposed soils will be regularly sprayed with water or other dust suppressants. Painted Hills Residential Development | Spokane Valley, Washington Page 72 Final Environmental Impact Statement  Cleared area that will be exposed for prolonged periods will be paved, planted with a vegetation ground cover, or covered with gravel.  Loads in trucks will be covered to ensure that dust and soil does not fly off and pollute the air.  A program and schedule for road sweeping will be submitted concurrent with submittal of an application for the first phase or sub-phase of development.  Woody vegetation cleared from the site will not be burned but will instead be ground or chipped on- site or hauled to an off-site location. Operations: The following measures could reduce air quality effects associated with either Alternative 2a or 2b:  Implementation and enforcement of Spokane Clean Air burn bans/restrictions by the HOA to minimize the length and intensity of poor air quality conditions during the winter months.  Incorporation of open spaces, such as in Alternatives 2a and 2b, and retention of vegetation and planting of trees within the project can help mitigate atmospheric carbon indirectly generated as a result of the project.  Revegetation of open space areas and other areas of the site disturbed by construction, and the planting of street trees. 3.4.1.4 Cumulative Effects Local air quality, which is already compromised at times during the winter months in most years due to current levels of wood smoke-generated pollution would likely be further diminished for potentially longer periods of time during the winter months due to the added emissions from the project. The incremental air quality impacts of the project are consistent with the anticipated implementation of the City’s comprehensive plan, which designates the site for residential development. 3.4.2 Aesthetics 3.4.2.1 Affected Environment The Painted Hills site, which was previously a golf course, is currently a vacant field with scattered trees associated with the former golf course. The former golf course clubhouse located at the southwest corner of the site remains and is currently operated as a restaurant with associated parking. Vegetation on the site is primarily field grasses with intermittent deciduous and evergreen trees that line the former fairway areas. Uses surrounding the site include:  Low density residences located to the east and on the east side of South Madison Road;  A single-family residential subdivision located adjacent to the northern limits of the site;  A convent, the “Carmel of the Holy Trinity”, located adjacent to the northwest boundary of the property; Painted Hills Residential Development | Spokane Valley, Washington Page 73 Final Environmental Impact Statement  A church, owned by the Chester Community Church, also adjacent to the northwest limits of the site; and  Vacant land, zoned Corridor Mixed Use, located west of the site on the opposite side of South Dishman-Mica Road. In addition to the views from these surrounding properties, the site can be viewed by passing motorists from the surrounding roads: South Madison Road (Figure 3-10), East Thorpe Road (Figure 3-11) and South Dishman- Mica Road (Figures 3-12 and 3-13). The site is not designated as a scenic resource and there are no scenic by- ways or other scenic areas designated on or adjacent to the site. There are currently no sources of noise or light on the site, except for the commercial use of the former clubhouse and the parking lot area (Figure 3-14), which includes overhead parking lot lighting. 3.4.2.2 Environmental Consequences 3.4.2.1.1 Alternative 1 – No Action No aesthetic impacts are anticipated to result from the No Action alternative. In this scenario, site conditions would remain in their state. 3.4.2.1.2 Alternative 2a – High Infiltration Scenario Under Alternative 2a, large portions of the site would be converted from ungroomed prairie into single-family residences, commercial retail development, apartments, landscaped open space areas. Due to the nature of the proposal as a PRD, the project is required to provide a minimum of 30 percent of the site in public open spaces. 3.4.2.1.2 Alternative 2b – Low Infiltration Scenario Under Alternative 2b, the project would be developed as a PRD and the minimum 30 percent open space requirement would still apply. Development impacts would be similar to Alternative 2a as areas of the site would be converted from ungroomed prairie into single-family residences, commercial retail development, apartments, and open space areas. 3.4.2.3 Mitigation Measures Under the build alternatives 2a and 2b, project compliance with the City’s landscaping and open space standards in conjunction with site development will ensure that the aesthetic impacts of the project are addressed. Painted Hills Residential Development | Spokane Valley, Washington Page 74 Final Environmental Impact Statement Figure 3-10: Study Area Intersections Painted Hills Residential Development | Spokane Valley, Washington Page 75 Final Environmental Impact Statement Figure 3-11: View of the Site from S. Madison Road Figure 3-12: View of the Site from E. Thorpe Road Painted Hills Residential Development | Spokane Valley, Washington Page 76 Final Environmental Impact Statement Figure 3-13: View of the Site from S. Dishman-Mica Road Figure 3-14: Former Clubhouse and Associated Parking Painted Hills Residential Development | Spokane Valley, Washington Page 77 Final Environmental Impact Statement 3.4.2.2 Environmental Consequences 3.4.2.2.1 Alternative 1 – No Action Because Alternative 1 would not result in any changes to the site, no aesthetic impacts are expected to result from this alternative. 3.4.2.2.2 Alternative 2a – Planned Residential Development—High Infiltration Development of the site under Alternative 2a would convert most of the central, east, and northwest areas of the site into a mixed-use community. Remaining undeveloped areas of the property would be retained as community open space. Under the City’s development standards for the R-3 zone, the maximum height of a residence is 35 feet. It is anticipated that new homes within the community would adhere to this maximum height standard. Open space areas would be landscaped and would include community amenities such as trails, benches, playground equipment, and other features. Streetlights conforming to the City’s public works standards would be incorporated into the development along perimeter public routes and new local roads. Parking lot lighting in the commercial area at the southwest corner of the site would be designed to meet City requirements. No aesthetic impacts are anticipated from off-site stormwater infrastructure improvements because these improvements will be at or below the existing ground surface and are not anticipated to result in any significant change in the character of these affected areas. During the initial public review of the PRD application, representatives of the Carmel of the Holy Trinity convent reviewed and commented on the application. As noted in their November 15, 2018 letter addressed to the City, convent representatives indicated a concern regarding a potential “influx of noise, traffic and other disturbances that are likely to arise both during construction of the project and upon its completion.” As noted in the November 15, 2018 letter, the project applicant has met with representatives of the convent to come to an agreement regarding specific measures that will be implemented to minimize and reduce aesthetic impacts of the project on this neighboring property. 3.4.2.2.3 Alternative 2b – Planned Residential Development—Low Infiltration As described for Alternative 2a, under Alternative 2b, most of the central, east, and northwest areas of the site would be converted into a mixed-use community. Remaining undeveloped areas of the property would be retained as community open space. As with Alternative 2a, under Alternative 2b, building heights, and streetlighting site would be designed to meet City requirements, and no aesthetic impacts are anticipated from off-site stormwater infrastructure improvements. 3.4.2.3 Mitigation Measures Alternative 1 No mitigation measures would be necessary under the no action alternative. Alternatives 2a and 2b  Streetlights and parking lot light fixtures would incorporate shields to ensure compliance with City foot-candle lighting requirements, mounting heights, and wattage.  Mitigation measures would be implemented consistent with those listed in the November 15, 2018, letter received from the Carmel of the Holy Trinity convent. Painted Hills Residential Development | Spokane Valley, Washington Page 78 Final Environmental Impact Statement 3.4.2.4 Cumulative Effects City and County development standards governing screening, setbacks, landscaping, light, glare, building height, and other provisions are expected to adequately address the aesthetic effects of individual development projects. Therefore, no significant cumulative aesthetic effects are expected to result when considering the action alternatives in conjunction with other potential development in the project vicinity. 3.4.3 Biological Resources 3.4.3.1 Affected Environment The affected biological environment of the Painted Hills site is defined in the February 28, 2019 Biological Evaluation (BE), Critical Areas Report and Habitat Management Plan, prepared by Biology, Soil & Water, Inc. (Biology, Soil, and Water Inc. 2019), and in a letter from Biology, Soil & Water, Inc. Dated June 5, 2022. The BE study area evaluated the biological resources within a half mile radius of the Painted Hills site and the potential impacts from Alternatives 2a and 2b. The June 2022 letter described conditions at the Triangle Pond and Gustin Ditch. As identified in the BE, the subject property is located within the Chester Creek valley with forested foothills on the east and west sides of the valley. The BE describes the habitats within the study area as a “mosaic of urban developed, fragments of conifer forest, and small tract agriculture.” As described in the BE, undeveloped forested hillsides extend about 1,200 feet east of the densely developed Ponderosa neighborhood. The BE notes that “large mammals that are willing to cross highways and residential developments interspersed with open farmland will find connectivity to a few hundred acres of wooded and sparsely populated foothills extending south and west from the Painted Hills site to Dishman Hills.” When the Painted Hills site operated as a golf course, the entire property was planted in non-native turf grasses with sparse conifer and deciduous trees lining some of the fairways. The turf grass was maintained by treatment with herbicides and regular mowing and maintenance of the golf course grounds. These practices virtually eliminated the native herbaceous plant community. Since the golf course operations and maintenance have ceased, noxious weeds have invaded the site. Honey willows were planted below the Ordinary High-Water Mark (OHWM) of Chester Creek whose channel was historically dredged and maintained for flood conveyance. The banks of the channel are covered with Reed canary grass. Outside the OHWM of the stream channel where the vegetation was not mowed or maintained, the vegetative community is dominated by Reed canary grass, teasel, tansy, thistle, wormwood, and lettuce. The creek is separated from the Painted Hills PRD site by a levee and the embankment of Dishman-Mica Road. The outer edges of the Triangle Pond are characterized by a narrow band of Ponderosa pine, snowberry and rose. Cheatgrass, bulbous bluegrass, and wormwood dominate the pond bottom. Vegetation on the banks and on the ditch bottom of the Gustin Ditch consists entirely of weedy upland plant species. Threatened or Endangered Species As identified in the BE, listed threatened and endangered species that occur in Spokane County include the Yellow-billed Cuckoo (Coccyzus americanus), Canada Lynx (Lynx canadensis), Bull trout (Salvelinus confluentus), Water Howellia (Howellia auqatilis) and Spalding’s Silene (Silene spaldingii). The BE presented the following findings regarding the potential presence of these species on the site:  Yellow-billed Cuckoo (Coccyzus americanus): These birds nest in areas with at least 25 acres of contiguous riparian woodland. Because the largest area of this habitat type on the site is less than one tenth of the minimum size suitable for the Yellow-billed Cuckoo, the BE concluded that there is no suitable habitat for the yellow billed cuckoo existing on the site. Painted Hills Residential Development | Spokane Valley, Washington Page 79 Final Environmental Impact Statement  Bull Trout (Salvelinus confluentus): Waterfalls and dams prevent the upstream and downstream migration of bull trout into the Spokane River and its tributaries in the vicinity of the Painted Hills site. There is no known population of bull trout in the project area; therefore, no Bull Trout habitat exists.  Canada lynx (Lynx canadensis): Typical lynx habitat is dense coniferous forest areas with sapling/pole thickets, rock outcrops, and wetlands at elevations of around 4,000 to 4,500 feet. The Painted Hills site is at an elevation of approximately 2,015 feet. Lynx dens typically occur in mature old growth stands with substantial deadfall and in areas where they can predate on snowshoe hare. No lynx on the site were observed in the field visits to the site and the Painted Hills site does not provide lynx habitat conditions.  Spalding’s catchfly (Silene spaldingii): Spalding’s catchfly is a plant species that is listed by the U.S. Fish and Wildlife Service (USFWS) as threatened in Washington State. Field studies conducted in support of the BE for the project failed to identify the presence of this plant on the site and the BE notes that “previous years of cultivation, followed by the planting of turf grasses, years of mowing and herbicide applications” have likely impacted the ability of the plant to grow on the site.  Water Howellia (Howellia aquatilis): Howellia is an aquatic plant that is often found in seasonal wetlands, ponds, and lakes. No evidence of this plant was observed through field visits conducted to support the preparation of the BE. Species of Concern The project BE also evaluated the presence of USFWS-listed species of concern on the site and evaluated the site for the presence and/or habitat of the following species that are listed in Spokane County.  Bald Eagle (Haliaeetus leucocephalus): The BE found that bald eagles do not routinely forage in the Action Area and no nest sites were observed on the Painted Hills site.  Western Burrowing Owl (Athene cunicularia): No historical observations have occurred in the project vicinity and no individuals, nests, or other signs were observed during the site survey.  California Floater (Anodonta californiensis): This is a freshwater mussel and there are no instances on the site.  Ferruginous Hawk (Buteo regalis): This raptor nests on rocky ledges or high ground vantage points and would not occur on the site.  Giant Columbia Spire snail (Fluminicola Columbiana): This species occurs in cold, unpolluted medium to large streams, which do not occur within the project area.  Loggerhead Shrike (Lanius ludovicianus): This robin-sized gray, black and white bird prefers nesting in big sagebrush and antelope bitterbrush. The BE determined that development at the Painted Hills site would not have an effect on this species.  Longeared Myotis (Myotis evotis): This species of vesper bat is sometimes found in crevices in small basalt rock formations. This species often roosts in Ponderosa pine trees over 30 centimeters (cm) in diameter and over 12 meters high. The BE identified that no significant effect would occur to this species.  Northern Goshawk (Accipiter gentilis): Goshawks select relatively closed canopy coniferous/boreal forest habitat for nesting. Therefore, the Painted Hills site does not provide nesting goshawk habitat. Painted Hills Residential Development | Spokane Valley, Washington Page 80 Final Environmental Impact Statement  Olivesided Flycatcher (Contopus cooperi): This species is found in boreal and western coniferous forests and the Painted Hill site does not provide this habitat.  Pallid Townsend’s Bigeared Bat (Corynorhinus townsendii pallescens): This species is found in eastside mixed conifer forest, shrub-steppe areas and riparian-wetland areas. In Washington, old buildings, silos, concrete bunkers, barns, caves, and mines are common roost structures. The Painted Hills site does not provide this habitat.  Peregrine Falcon (Falco peregrinus): Two subspecies of peregrine falcons occur in Washington state at present, Falco peregrinus pealei (Peale’s peregrine falcon) and Falco peregrinus anatum (Continental peregrine falcon). Peale's peregrine falcon is a coastal subspecies and are not found in eastern Washington. Therefore, the BE evaluated the potential presence of Continental peregrine falcon on the site. Historic use of Dichlorodiphenyltrichloroethane, more commonly known as “DDT”, throughout eastern Washington eliminated this subspecies from former breeding sites in eastern Washington. Since the ban of the use of DDT in 1972, attempts have been made to re-establish the Continental peregrine falcon in eastern Washington and captive-reared young birds have been released at several sites in Spokane County. The process of re-introducing falcons into the wild is called "hacking". Washington Department of Fish and Wildlife (WDFW) does not currently use any hack sites in the vicinity that could be impacted by the project. Further, because Peregrine falcons nest on cliffs or even man-made structures such as buildings or bridges, the Painted Hills site does not provide nesting habitat.  Redband Trout (Oncorhynchus mykiss): Chester Creek does not provide cool water habitat required by redband trout.  Sagebrush Lizard (Sceloporus graciosus): As suggested by its name, the Sagebrush lizard occupies habitats where sagebrush is prevalent, and the Painted Hills site does not provide such habitat.  Westslope Cutthroat trout (Oncorhynchus clarki lewisi): Chester Creek does not provide cool water habitat required by Westslope cutthroat trout.  Palouse Goldenweed (Haplopappus liatriformis): The Palouse goldenweed is a perennial grassland forb found in the Palouse bioregion of Idaho and southeastern Washington and does not occur on the Painted Hills site. WDFW Priority Species  White-tailed deer (Odocoileus virginianus): As illustrated on Figure 3-15, the Painted Hills site is not mapped by WDFW as White-tailed deer habitat, which is mapped to occur on wooded lands to the east and south. However, deer use the site as they do with all undeveloped parcels in the area.  Elk (Cervus canadensis): The Painted Hill site falls within the northern extent of the mapped Elk Habitat polygon in the Spokane Valley. The site does not provide cover or refugia required by elk and is therefore not elk habitat, but elk moving through the general area between Mica Peak and Dishman Hills could potentially cross the Painted Hills site to travel between these habitats. However, there is no documented record of regular use of the site by elk.  Gray Wolf (Canis lupus): The Painted Hills site is mapped as Gray wolf habitat and it is possible that wolves could travel through the site in search of prey. Because of the presence of small, domesticated mammals in the residential areas proximal to the site, the wolves could present a hazard to these neighboring residences. On May 5, 2011, wolves were delisted from the federally endangered species list in the eastern one-third of Washington state. Painted Hills Residential Development | Spokane Valley, Washington Page 81 Final Environmental Impact Statement Wetlands National Wetland Inventory (NWI) maps indicate the possible presence of two wetlands on the Painted Hills site. Field studies evaluated these sites and included seasonal hydrologic monitoring at test pits in these locations. The results of the on-site evaluation concluded that, although seasonal high-water conditions occur in the winter when snow or frozen ground conditions occur, wetland hydrologic conditions do not occur during the growing season and these sites therefore did not meet the hydrologic conditions necessary for these areas to be considered jurisdictional wetlands. This determination was verified by the Washington Department of Ecology (DOE), who conducted a field visit on June 8, 2016. Chester Creek and Riparian Areas Chester Creek infiltrates into the soil at its terminus northwest of the PRD site and is therefore hydrologically isolated from surface waters outside its watershed. The upper portions of the Chester Creek watershed are dominated by forests, pastures, row crops. Urbanization and livestock grazing in the lower portions of the watershed have severely restricted the historic floodplain of the creek. Summer baseflows in the creek are primarily maintained by groundwater inflows which typically remain consistently cool. There are anecdotal reports of fish occurrences in Chester Creek. Little submerged aquatic vegetation occurs in the creek. The Washington Department of Natural Resources (DNR) Water Type Map defines Chester Creek as a Type F waterway—a stream used by fish or that could potentially be used by fish. Chapter 21.40 of the City of Spokane Valley Municipal Code designates Chester Creek, as a Type F stream with a width of greater than 15 feet at bankfull stage, requiring a standard riparian buffer or “riparian management zone” of 100 feet. Biology, Soil & Water, Inc. (2019) delineated the Chester Creek OHWM in the field on March 31, 2015, to establish the extent of this buffer. Threatened or Endangered Species (Chester Creek) As identified in the BE, listed threatened and endangered species that occur in Spokane County include the Yellow-billed Cuckoo (Coccyzus americanus), Canada Lynx (Lynx canadensis), Bull trout (Salvelinus confluentus), Water Howellia (Howellia auqatilis) and Spalding’s Silene (Silene spaldingii). Specific to Chester Creek, the BE presented the following findings regarding the potential presence of these species on the site:  Bull Trout (Salvelinus confluentus): Waterfalls and dams prevent the upstream and downstream migration of bull trout into the Spokane River and its tributaries in the vicinity of the Painted Hills site. There is no known population of bull trout in the project area; therefore, no Bull Trout habitat exists.  Water Howellia (Howellia aquatilis): Howellia is an aquatic plant that is often found in seasonal wetlands, ponds, and lakes. No evidence of this plant was observed through field visits conducted to support the preparation of the BE. Species of Concern (Chester Creek) Specific to Chester Creek, the BE presented the following findings regarding the potential presence of these species of concern on the site:  California Floater (Anodonta californiensis): This is a freshwater mussel and there are no instances on the site.  Giant Columbia Spire snail (Fluminicola Columbiana): This species occurs in cold, unpolluted medium to large streams, which do not occur within the project area.  Redband Trout (Oncorhynchus mykiss): Chester Creek does not provide cool water habitat required by redband trout. Painted Hills Residential Development | Spokane Valley, Washington Page 82 Final Environmental Impact Statement  Westslope Cutthroat trout (Oncorhynchus clarki lewisi): Chester Creek does not provide cool water habitat required by Westslope cutthroat trout. Figure 3-15: Priority Habitat & Species Painted Hills Residential Development | Spokane Valley, Washington Page 83 Final Environmental Impact Statement 3.4.3.2 Environmental Consequences Calculation of the extent of impacts to the Chester Creek riparian buffer was completed in 2019 and was based on the proposed lot configuration that was presented as Alternative 2 in the 2019 FEIS submittal. As described in Section 2.2 Land Development Alternatives, the 2019 Alternative 2 has been replaced by Alternatives 2a and 2b in this current SEPA documentation. The extent of permanent impacts to the riparian buffer resulting from Alternatives 2a or 2b would be less than those calculated for the 2019 Alternative 2. Once an alternative is selected, the exact extent of riparian buffer impact and required mitigation would be calculated for that alternative prior to the submittal of permit documents to the City. 3.4.3.2.1 Alternative 1 – No Action Under Alternative 1, there would be no physical changes to the site. Vegetation established and maintained under the former golf course use would continue to exist on the site but would not receive the extent of maintenance that occurred under golf course operation. Existing built features on the site, including the restaurant, maintenance building, former cart paths, and two cart path bridges would continue to occupy the regulated riparian buffer of Chester Creek. No other impacts to biological resources are anticipated to occur under Alternative 1. 3.4.3.2.2 Alternative 2a – Planned Residential Development—High Infiltration Under Alternative 2a, portions of the existing cart path that currently occupy the regulated riparian buffer would be demolished, removed from the buffer area, and revegetated, resulting in an increase in the areal extent of vegetated riparian buffer. New permanent riparian buffer impacts would occur as a result of a planned expansion of the restaurant parking area and for the required expansion of Thorpe Road. These improvements would result in approximately 4,000 SF and 1,400 SF of permanent buffer loss, respectively. Permanent impacts to the riparian buffer would be allowed under the SVMC through a combination of buffer averaging and buffer reduction. All impacts to riparian buffers due either to permanent removal or through buffer averaging would be mitigated at ratios either equal to or greater than what is required in the SV critical areas ordinance to ensure that these impacts do not result in a reduction in the ecological function and values of the riparian area. Alternative 2a is not expected to negatively impact the Chester Creek channel. The widening of the Thorpe Road bridge over Chester Creek under Alternative 2a would result in additional shading of the creek channel, potentially reducing summer stream temperatures. Stormwater generated on the PRD site will be collected and treated in the stormwater management system and will not discharge directly to Chester Creek and therefore will not significantly impact water quality. As described above, neither the Triangle Pond nor the Gustin Ditch provide unique or important habitat for fish, wildlife, or native plants. The project-generated site disturbance from installation of drywells in the bottom of the Triangle Pond, and the piping of the Gustin Ditch under Alternative 2a are not expected to negatively impact biological resources. Chester Creek Base Flows and Fish Habitat Chester Creek has not been reported to support special status fish or protected plant species according to the Biological Evaluation (BE) for the Painted Hills PRD and Triangle Pond/Gustin Ditch site prepared by Larry Dawes in November 2021. The BE report concludes that there are no listed species present in the vicinity of the project site and that waterfalls and dams prevent the upstream and downstream migration of fish into the Spokane River and its tributaries in the vicinity of the Painted Hills PRD site. Potential risks to Chester Creek and fish habitat could include scouring in the event of a 100-year flood event or contaminations resulting from stormwater runoff. Painted Hills Residential Development | Spokane Valley, Washington Page 84 Final Environmental Impact Statement Under Alternative 2a, no significant negative impact on Chester Creek or fish habitat is anticipated due to riparian corridor mitigation/buffer enhancements and erosion control measures implemented in conjunction with construction. Buffer enhancement along the southern shore of Chester Creek will include the planting of native vegetation that will provide multiple benefits, including shading the creek, improving biodiversity, and reduce the potential for scouring and erosion along the creek. The flood conveyance system is designed to contain and convey floodwaters that overtop the banks of Chester Creek south of the Painted Hills site. Therefore, the flood conveyance improvements would not impact the fish-bearing capacity and habitat of Chester Creek. Additional information regarding the design of the flood conveyance system can be located in Section 3.2 of this FEIS. 3.4.3.2.3 Alternative 2b – Planned Residential Development—Low Infiltration Impacts to riparian buffers under Alternative 2b would be the same as those described under Alternative 2a and would be mitigated as described for Alternative 2a. 3.4.3.3 Mitigation Measures  Impacts to City-regulated riparian buffers will be mitigated to ensure no net loss of overall buffer area consistent with the applicable City critical areas ordinance.  Water quality will be protected in Chester Creek during construction through the implementation of standard construction stormwater best management practices.  Protected buffer areas that are inadvertently disturbed during construction will be replanted with native riparian vegetation.  Permanent signage will be placed along the limits of the riparian buffer indicating that the area is not to be disturbed. 3.4.3.4 Cumulative Effects No cumulative effects on biological resources are expected to result from the project. 3.4.4 Environmental Health 3.4.4.1 Affected Environment Because the site has primarily been used as open space as a golf course, the site does not have a known history that would indicate the presence of environmental health hazards. Further, no evidence exists of environmental health risks on the site. Ecology’s online “What’s in My Neighborhood” mapping tool indicates that there are no designated clean-up sites on the site or in the immediate vicinity of the project (DOE, 2018).9 The nearest site is approximately 1.5 miles to the north. Further, the Ecology Spills Map does not indicate any history of hazardous spills on the site.10 Lastly, the U.S. Department of Health & Human Services TOXMAP Environmental Health Maps (2018) doesn’t show any other toxic chemicals in the area and indicates that the nearest landfill to the site is approximately 2.25-miles to the southeast. 9 https://fortress.wa.gov/ecy/neighborhood/ 10 https://fortress.wa.gov/ecy/coastalatlas/storymaps/spills/spills_sm.html Painted Hills Residential Development | Spokane Valley, Washington Page 85 Final Environmental Impact Statement Site surveys have not revealed any past septic fields on the property. There is one known well on the site. Well logs from the Washington State Department of Conservation and Development indicate that this well was dug in 1950. It is expected that this well will be decommissioned and capped with future site development. 3.4.4.2 Environmental Consequences 3.4.4.2.1 Alternative 1 – No Action The No Action alternative is not anticipated to have any environmental health impacts as no changes would occur. 3.4.4.2.2 Alternative 2a – Planned Residential Development—High Infiltration Alternative 2a would have the potential to cause environmental health effects due to the following:  Dust and construction equipment emissions during site construction.  Noise from construction equipment. 3.4.4.2.3 Alternative 2b – Planned Residential Development—Low Infiltration Similar to Alternative 2a, Alternative 2b would have the potential to generate environmental health effects from dust and construction equipment emissions and from construction noise. 3.4.4.3 Mitigation Measures It is anticipated that environmental health effects from Alternatives 2a and 2b would be mitigated through the following measures:  Site construction will be conducted consistent with SVMC Section 7.05.040 (Nuisances Prohibited) which includes limits on smoke, soot, toxic substances, noise, and other public health hazards.  Site construction will abide by the maximum allowable levels for environmental noise related to site construction as governed by Washington Administrative Code (WAC) Section 173-60. 3.4.4.4 Cumulative Effects No cumulative effects on environmental health are anticipated to result from the project. 3.4.5 Geology 3.4.5.1 Affected Environment The Painted Hills site is generally flat, sloping less than one percent from south to north with some localized short, steeper slopes associated with remnant golf course features including tee boxes, greens, and road embankments. The majority of the site is mapped by the Natural Resources Conservation Service (NRCS) as Narcisse silt loam, zero to three percent slopes, prime farmland. The edges of the site are mapped as Hardesty ashy silt loam, zero to three percent slopes, prime farmland; Urban land-Springdale, disturbed complex zero to three percent slopes; Endoaquolis and Fluvaquents, zero to three percent slopes, prime farmland if drained; and Phoebe shay sandy loam, zero to three percent slopes, prime farmland if irrigated. Across most of the project site beneath the topsoil, there is a layer of somewhat poorly drained alluvial soils, and below this layer are glacially deposited sands and gravels. There is no known history of unstable soils on the site or within the immediate vicinity. Painted Hills Residential Development | Spokane Valley, Washington Page 86 Final Environmental Impact Statement 3.4.5.2 Environmental Consequences 3.4.5.2.1 Alternative 1 – No Action No significant impacts to surface soils are proposed under Alternative 1. 3.4.5.2.2 Alternative 2a – Planned Residential Development—High Infiltration Under Alternative 2a, the native soils will be covered by imported fill and developed for residential or residential and commercial uses. The property will be graded to create the streets, drainage ponds/swales, building pads, parking lots, and park features. Grading may require up to 377,532 CY of imported material after accounting for a 15 percent shrink factor. This material will come from the nearest source approved per City and County standards and brought to the site following City guidelines. Approximately 30 percent of the site would be covered with impervious surfaces after completion of the project. Due to the placement of fill and the site development features proposed under Alternative 2a, the opportunity for surface water and precipitation to recharge the underlying aquifer will be limited to the proposed infiltration basin, roadside swales, and dry wells. Some erosion from wind and minor erosion from rain could occur on-site during construction. Because of the flatness of the site, the potential for erosion caused by surface water is limited and would be localized to the area of work. 3.4.5.2.3 Alternative 2b – Planned Residential Development—Low Infiltration As described for Alternative 2a, site grading activities associated with Alternative 2b would cover most of the site with imported fill. The property would be graded to create the streets, drainage ponds/swales, and areas future residences. Alternative 2b is expected to require the import of approximately 117,697 CY of “loose” fill material prior to compaction on the site. Approximately 25 percent of the site would be covered with impervious surfaces after completion of the project. As described for Alternative 2a, due to the placement of fill and site development features under Alternative 2b, the opportunity for surface water and precipitation to recharge the underlying aquifer will be limited to the proposed infiltration basin, roadside swales, and dry wells. Some erosion from wind and minor erosion from rain could occur on-site during construction. Because of the flatness of the site, the potential for surface water erosion is limited and would be localized to the area of work. 3.4.5.3 Mitigation Measures The following mitigation measures will be implemented to reduce or control erosion under the two action alternatives, Alternatives 2 and 3.  Measures as required by the SRCAA and WDOE permits would be followed.  An erosion control plan that complies with the Eastern Washington Stormwater Management Manual (EWSWMM) and SRSM would be developed for the project and will be implanted during construction. Painted Hills Residential Development | Spokane Valley, Washington Page 87 Final Environmental Impact Statement  Erosion control measures to be implemented during construction may include using silt fences, wattles, sediment basins, inlet protection, watering and hydro-seeding as allowed/required by the SRSM and the EWSWMM.  Following construction, soils would be stabilized by paving, building, and landscaping/vegetation. 3.4.5.4 Cumulative Effects Alternatives 2a and 2b are not expected to result in cumulative effects to surface geology, as there are no known on-going or concurrent projects that, when considered in conjunction with the action alternatives, could generate cumulate effects. 3.4.6 Historic, Cultural, and Archaeological Resources 3.4.6.1 Affected Environment The affected environment of the Painted Hills site is described in detail in an April 2018 Cultural Resource Survey, prepared by Plateau Archaeological Investigations, LLC (PAI) and incorporated into this FEIS by reference (PAI, 2018). As described in the study, PAI conducted an intensive pedestrian survey over the Painted Hills site and supplemented that with desktop research. Upon completion of the study, PAI concluded that development of the Painted Hills PRD project (Alternatives 2a and 2b) “will result in No Historic Properties Affected, and no further archaeological investigations are recommended prior to, or during, execution of this project.” Although this survey revealed no indication that cultural or historic materials would be encountered during construction, PAI recommended that all ground-disturbing activities associated with the project be conducted under the guidance of an Inadvertent Discovery Plan (IDP) due to interest expressed in the project by the Spokane Tribe of Indians. The IDP is included with the cultural resources survey, which is included with this FEIS as Appendix I. 3.4.6.2 Environmental Consequences 3.4.6.2.1 Alternative 1 – No Action No potential impacts to historic, cultural, or archaeological resources would result from Alternative 1 as no site disturbance would occur. 3.4.1.2.2 Alternative 2a--Planned Residential Development—High Infiltration As noted in the cultural resource survey, subsurface probing on the Painted Hills site revealed irregular sediments that “generally did not fit those predicted by the NRCS model” due to the extensive landscaping and site grading that occurred with the construction of the Painted Hills Golf Course. Due to the site disturbance that has occurred on the site and the lack of evidence of any Native American or historic-era cultural materials or features, no significant impacts are anticipated to result from the construction activities associated with Alternative 2a. However, site construction activities will occur under the guidance of an IDP as outlined in the Cultural Resources Survey included in Appendix I of the Cultural Resources Survey to ensure that any potential inadvertent discovery is promptly addressed. A March 2022 supplemental report prepared by Plateau Archaeological Investigations LLC is included in Appendix J. As noted in that report, no archaeological resources were found within the area of potential effects associated with the off-site improvements proposed at the Gustin Ditch and the Triangle Pond. Therefore, no impacts to archaeological resources are anticipated on off-site areas under Alternative 2a. Painted Hills Residential Development | Spokane Valley, Washington Page 88 Final Environmental Impact Statement 3.4.6.2.3 Alternative 2b – Planned Residential Development—Low Infiltration As described for Alternative 2a, areas of site disturbance for Alternative 2b would occur within the same site limits as those evaluated in the cultural resources survey. As a consequence, no significant impacts to Native American or historic-era cultural materials would be expected to result from Alternative 2b. However, site construction activities would occur under the guidance of an IDP as outlined in the Cultural Resources Survey in Appendix I to ensure that any potential inadvertent discovery is promptly addressed. A March 2022 supplemental report prepared by Plateau Archaeological Investigations LLC is included in Appendix J. As noted in that report, no archaeological resources were found within the area of potential effects associated with the off-site improvements proposed at the Gustin Ditch and the Triangle Pond. Therefore, no impacts to archaeological resources are anticipated on off-site areas under Alternative 2b. 3.4.6.3 Mitigation Measures On-site and off-site ground disturbance activities would follow the IDP included in the April 2018 Cultural Resource Survey document. This IDP includes the following measures:  If ground-disturbing activities reveal potential Native American or historic-era cultural materials or features, a professional archaeologist will be contacted immediately. The archaeologist will meet the Secretary of the Interior’s standards for a professional archaeologist as defined at 36 CFR 61 (See Appendix I). Construction within 200 feet (60 meters) of the discovery will stop, and the area will be secured to protect the find from additional damage. The archaeologist will document the find, prepare a brief written statement, and take photographs of the find for submission to the lead agency and the State Historic Preservation Officer (SHPO) at the Department of Archaeology and Historic Preservation (DAHP). The find will also be reported to the Tribal Historic Preservation Officer (THPO) of the Spokane Tribe of Indians. It is the responsibility of the lead agency, Washington State Department of Archaeology and Historic Preservation, to contact the affected Tribes. This consultation process will take place even if the pre-contact or historic-era cultural materials appear to have lost their depositional integrity. Work within 200 feet (60 meters) of the find will not resume until a plan for management or preservation of the materials has been approved. Following the project, the archaeologist will provide a report detailing the procedures and results of the investigation.  During the investigation, the archaeologist will observe rules of safety and will comply with any safety requirements of the excavation contractor and project engineers. Entry into any excavation will only be done under the direct supervision and approval of the construction foreman (or his or her agent) and verification that entry and exit is safe.  If a burial, human remains, suspected human remains, funerary objects, sacred objects, or items of cultural patrimony are encountered during any aspect of this project, operations will cease in accordance with the RCW Chapters 27.44, 68.50, and 68.60. All work within 200 feet (60 meters) of the find will cease, the area around the discovery will be secured, and any requirements of the lead agency shall be followed. Work within 200 feet (60 meters) of the find will not resume until a plan for management or preservation of the materials has been agreed upon by all parties. o If the lead agency does not explicitly state procedures, the Spokane Valley Police Department, the Spokane County Medical Examiner, and the SHPO at the DAHP will be notified in the most expeditious manner possible. The find will also be reported to the THPO of the Spokane Tribe of Indians. Reporting is to be done by the lead agency (DAHP), or a federal or state funding or permitting agency. The find will be treated with dignity. People who have contact with the find will not take photographs, contact the press, call 911, or discuss the find with the public in any manner. The find will be covered, and the location kept secure. Painted Hills Residential Development | Spokane Valley, Washington Page 89 Final Environmental Impact Statement o The coroner and law enforcement agency with jurisdiction will evaluate the find to determine whether it is a crime scene or a burial. If human remains are determined to be associated with an archaeological site (burial), and if there is any question of the cultural affiliation of the burial, or whether the burial is prehistoric, the DAHP and any affected tribes will be notified to assist in the determination prior to beginning any extensive excavations. 3.4.6.4 Cumulative Effects No on-going or future activities are expected to occur on-site that would result in cumulative effects when considered in conjunction with any of the project alternatives. 3.4.7 Noise 3.4.7.1 Affected Environment Noise levels in the project area are relatively low, as would be expected in a low-density semi-rural setting. Noise in the area is typically generated by vehicular traffic on the surrounding roads, and residential equipment such as lawn mowers and chain saws. Noise from recreational vehicles and snowmobiles, in season, may also be present. The proposed project is subject to State of Washington and City of Spokane Valley noise standards and regulations. State of Washington noise regulations are found in WAC 173-60. Traffic traveling on public roadways is exempt from the State of Washington’s maximum allowable noise levels, as is construction noise that occurs between the hours of 7:00 a.m. and 10:00 p.m. Section 7.05.40 K. of the SVMC provides thresholds and standards for controlling the nuisance impacts of noise within the community. This section includes exemptions regardless of time of day for normal use of public rights-of-way, sounds created by motor vehicles when regulated by Chapter 173-62 WAC (noise emission standards for new motor vehicles and noise emission standards for the operation of motor vehicles on public highways), sounds created by surface carriers engaged in commerce or passenger travel by railroad, and sounds created by safety and protective devices where noise suppression would defeat the intent of the device or is not economically feasible. In addition, sounds originating from temporary construction sites as a result of construction activity are exempt from the provisions of SVMC 7.05.040(K)(1) between the hours of 7:00 a.m. and 10:00 p.m., or when conducted beyond 1,000 feet of any residence where human beings reside and sleep at any hour: 3.4.7.2 Environmental Consequences 3.4.7.2.1 Alternative 1 – No Action Under Alternative 1 noise levels on and near the project site would remain at current low levels typical of rural residential areas. 3.4.7.2.2 Alternative 2a – Planned Residential Development—High Infiltration Under Alternative 2a, noise levels would increase beyond current noise levels both during the construction phase and indefinitely once the project construction is completed. During the construction phase noise from construction, land clearing, fill delivery, and placement equipment as well as structure construction would increase for the short term. Following completion of construction, noise would be generated by residential traffic and other residential sources including yard maintenance equipment, domestic pets, occupants, and park use for the long term. Painted Hills Residential Development | Spokane Valley, Washington Page 90 Final Environmental Impact Statement The increase in population under Alternative 2a would likely lead to noise levels that are higher than current levels. It is unlikely that the increase would be measurable, but it may be perceived by residents in terms of the frequency to which they experience noise disturbance. 3.4.7.2.3 Alternative 2b– Planned Residential Development—Low Infiltration Under Alternative 2b, noise levels would increase beyond current noise levels both during the construction phase and indefinitely once the project construction is completed, to approximately the same degree as described for Alternative 2a. 3.4.7.3 Mitigation Measures Under either Alternative 2a or 2b, construction will be limited to times prescribed in City code. 3.4.7.4 Cumulative Effects There are no known off-site sources of noise that could present cumulative effects when considered in conjunction with the action alternatives. 3.4.8 Public Services The location of service districts, including schools, irrigation, water currently serving the project vicinity are identified on Figure 3-15 Service District Boundaries. 3.4.8.1 Affected Environment Schools The Painted Hills PRD Site is located in the Central Valley School District (CVSD) which currently has a population of over 14,000 students. According to the CVSD webpage, enrollment is projected to increase by over 3,000 students by 2029. The nearest schools in proximity to the project site are Horizon Middle School, Chester Elementary School and University High School, which are located together on an approximately 75-acre campus immediately northeast of the Painted Hills site on the east side of South Pines Road and between East 32nd Avenue and East 40th Avenue. The Painted Hills Site currently contains no residences and therefore has no direct impact on school capacity in the CVSD. The funding of public K-12 schools in Washington State comes from a variety of sources including retail sales tax, business and occupation tax, property taxes and other sources distributed by the state to local school districts. In addition, local school districts have the ability to supplement funding for maintenance and operations and capital improvements through local levies and bonds. School districts also have the ability under the Growth Management Act and pursuant to RCW 82.02.050(4) and RCW 82.02.090(7) to establish a capital facilities plan that can be integrated into the county’s comprehensive plan and serve as the basis for the collection of school impact fees. As acknowledged in Spokane County’s January 2020 Capital Facilities Plan, “Since capital facilities plans are not mandatory for special districts under GMA, Spokane County has no way of compelling a school district to prepare a plan unless they want a school impact fee.” To this date, CVSD has elected not to pursue school impact fees on new residential development as allowed under state law and has instead opted to pursue bond funding for capital improvements when necessary. As reported by the Spokane County Assessor’s office, in 2021 CVSD obtained $29,211,000 from an enrichment levy and $17,130,000 from a bond levy for new improvements. These revenues were based on an assessment of $2.32 per $1,000 of assessed property value for the enrichment levy and $1.36 per $1,000 of assessed property value for the bond levy. Painted Hills Residential Development | Spokane Valley, Washington Page 91 Final Environmental Impact Statement According to the Spokane County tax records, the approximately 84-acre parcel within the Painted Hills Site in which single family and multi-family residences would be located, Parcel 45336.9192, is currently classified by the county appraiser as a recreational use, due to its historic golf course use and on-going use as a golf driving range. The total taxable market value for this parcel in 2021 was $1,827,910 and the total annual tax assessment for this parcel was $21,102.73. Based on the current CVSD enrichment levy rate of $2.32 per $1,000 of taxable value and the CVSD bond levy rate of $1.36 per $1,000 of taxable value, the 84-acre site that comprised a majority of the project site will contribute $4,241 in enrichment levy revenue and $2,486 in bond levy revenue towards the CVSD levies in 2022. Fire The Painted Hills PRD site is located in the Spokane Valley Fire District, approximately 0.6 miles from Spokane Valley Fire Department Station 9. Access to the site by emergency vehicles is provided from multiple avenues including S Madison Road, SE 32nd Avenue to S. Bowdish Road and S Dishman Mica Road. Spokane Valley Fire District operates under a Maintenance and Operation (M&O) levy. Public Safety The Painted Hills PRD site is provided emergency medical services by the Spokane Valley Fire District. Emergency medical services are anticipated to transport patients to the nearest hospital, Multicare Valley Hospital, approximately 4.2 miles from the project site. The City of Spokane contracts with the Spokane County Sheriff’s office to provide public safety services. The Spokane County Sheriff’s department operations and facilities are funded by taxes levied on properties within the district. Therefore, district resources grow as assessed values within the district grow. Water Water service is provided by Spokane County Water District #3. Existing water lines run throughout the developed portions of the Painted Hills PRD site. Water lines on Thorpe Road are eight-inch steel and 20-inch ductile iron lines. Water lines on Madison are 10-inch and 18-inch ductile iron lines. Waterlines along Dishman- Mica are 12-inch steel lines. Water service is funded by connection fees, monthly base charges, and consumption charges per cubic foot. Therefore, funding for services is anticipated to be commensurate with development. Sanitary Sewer Sanitary sewer service to the site is provided by Spokane County Environmental Services. A sewer main is located along the western property line fronting Dishman Mica Road. A pump station identified as Midilome #5 is located in the northwestern corner of the property. Sanitary sewer lines range from 10 to 12 inches on Thorpe, and 24 inches on Dishman-Mica. Additional sewer lines of varying sizes are available north of the site, as identified on the existing conditions plat. Sanitary sewer utilities are funded by monthly rates and connection fees. Funding for services is anticipated to be commensurate with development. Painted Hills Residential Development | Spokane Valley, Washington Page 92 Final Environmental Impact Statement Energy Electrical utilities will be provided to the Painted Hills PRD site by Inland Power Company. According to a map received from Inland power, existing utility lines run throughout the developed portions of the Painted Hills PRD site. Existing electrical lines include 3-phase overhead power on Dishman-Mica and Thorpe Road, and 3- phase underground power along the northern property line and Madison Road to a point of termination on Parcel 45343.9059. The Painted Hills PRD site has several existing junction boxes and transformers. No substantial transmission improvements are necessary to provide an adequate level of service. Electric utilities are funded by residential rates and other charges, commensurate with development. Power design and distribution lines internal to the site will be coordinated with Inland Power’s Senior Field Engineer, consistent with the service provider and city standards. 3.4.8.2 Environmental Consequences 3.4.8.2.1 Alternative 1 – No Action No significant impacts to public services (schools, public safety, and public and private utilities) are anticipated to result from the no-action alternative as no appreciable additional demand on services would occur. Existing demand on public services would remain relatively static and contributions towards public services through property taxes and utility rates would be expected to remain roughly in-line with inflation and any other market adjustments. 3.4.8.2.2 Alternative 2a – Planned Residential Development—High Infiltration Alternative 2a would result in approximately 300 single-family residential units, 228 multi-family units, and 52 mixed-use residential units. Approximately 13,400 SF of commercial use will occur within the mixed-use buildings and approximately 9,000 SF of new retail use will occur within a newly created 92,865 SF lot located along Dishman-Mica Road. The 4,000 SF former clubhouse building will be retained in restaurant use and, as a result, would not represent a change in impact on public services. Based on current demographics, it is expected that approximately 1,377 people would reside in the project at full project buildout. Further, it is anticipated that approximately 45 employees would work in the 22,400 SF of new retail space that would result with Alternative 2 .11 Similar to the projected schedule of residential development, it is anticipated that development of the commercial retail uses will be market-driven and would occur over the approximately 10-year buildout period of the project. The following paragraphs summarize the anticipated effects of these uses and the new residents and employees on schools, parks, fire, public safety, water and sanitary sewer services. Schools Based on the U.S. Census Bureau American Community Survey (ACS) 5-year estimate data, approximately 15.2 percent of Spokane Valley’s population is between the ages of 5 and 17 years old. Extrapolating this number to the Painted Hills project results in an estimated 209 students who would reside within the project upon completion of Alternative 2a. 11 Assumes approximately 1,000 square feet of retail space per employee and two shifts per day, or approximately 500 square feet of retail area per employee. (U.S. Energy Information Administration (2016) - https://www.eia.gov/consumption/commercial/data/2012/bc/cfm/b2.php) Painted Hills Residential Development | Spokane Valley, Washington Page 93 Final Environmental Impact Statement While the precise cohort of elementary school, middle school, and high school students is not known, if general student population were proportionately distributed to the number of grades in elementary (six grades), middle school (three grades), and high school (four grades), it is assumed that the development of Alternative 2a would result in the following increases in student population:  Elementary School – Approximately 10 new students per year or 96 total students over the approximately 10-year buildout of the project.  Middle School – Approximately five new students per year or 48 total students over the approximately 10-year buildout of the project.  High School – Approximately six new students per year or 64 total students over the approximately 10- year buildout of the project. It is expected that the future development under Alternative 2a would provide increased school tax revenues commensurate with the demand on facilities and operations created by additional school children residing within the PRD. For example, if the current CVSD enrichment levy and bond levy were to be maintained at its current rate, it is estimated that, at full buildout of the project, approximately $483,645 per year in enrichment funding and $283,516 in bond levy funding would be generated by the project. Painted Hills Residential Development | Spokane Valley, Washington Page 94 Final Environmental Impact Statement Table 3-10: Alternative 2A. Estimated Potential Annual Levy Funds Generated at Buildout Land Use # Units / Acres Estimated Present Day Market Value1 2022 Enrichment Levy Rate Potential Annual Enrichment Levy Funds2 2022 Bond Levy Rate Potential Annual Bond Levy Funds* SFR 300 $150,000,000 0.00232 $348,000 0.00136 $204,000 MFR 228 $45,600,000 0.00232 $105,792 0.00136 $62,016 COM 52 units / 3.29-A $12,867,500 0.00232 $29,853 0.00136 $17,500 Total $483,645 $283,516 1. Values based on $500,000 per SFR unit, $200,000 per MFR unit and $750,000 per acre for Commercial land. 2. Assumes current levy rates are maintained through project buildout. Ultimately, it is the responsibility of the local school district—in this case CVSD-to ensure that adequate facilities are in place for student populations as they grow over time. If revenue streams are inadequate to expand to build new facilities at any given point when capacities are stretched, districts have the responsibility of accommodating students through other means including redrawing the boundaries for schools within their system and/or finding auxiliary facilities to even the distribution of populations until any needed capital facilities can be built. The district has the ability to supplement revenue received by the state with supplemental funding and currently exercises that ability through two levies, one for enrichment (programs) and one for capital improvements (bond levy). While these levies expire over time, if renewed at their current rates, it is anticipated that the project would generate approximately $283,516 per year at project completion towards capital improvement funds. Also, if CVSD determined it was in their best interest, they could elect to collaborate with Spokane County to adopt a GMA-compliant capital facilities plan and establish a school impact fee program for new development. Such a fee would be a one-time assessment on new residential construction that would be used to fund new school facilities identified in the capital facilities plan. In summary, it is not anticipated that the Painted Hills PRD will result in significant impacts to schools for the following reasons:  Student population increase from the project will occur slowly over time—approximately 21 students per year over the 10-year buildout horizon of the project—giving the district time to plan for any necessary adjustments to alter its population distribution and facilities as needed.  Prior to the 10-year buildout, it is expected that approximately two (2) years of site development would occur before any new residential structures would be constructed and any students would reside on the site. Therefore, the district would have at least one (1) to two (2) years following an approval of the Painted Hills PRD to make any initial adjustments necessary to accommodate expected near term changes in student population represented by the project.  Capital facilities revenues received by the district under current and future levies and/or other capital revenue streams will grow from the project, helping to off-set the impact on school capacity and providing the CVSD with additional means of building new facilities if needed.  The CVSD has other revenue-generating mechanisms that it could pursue if desired including the establishment of school impact fees. Painted Hills Residential Development | Spokane Valley, Washington Page 95 Final Environmental Impact Statement Fire In response to the submittal of the Painted Hills PRD application, the Spokane Valley Fire District submitted a letter, dated August 31, 2015, that provides development-specific recommendations for ensuring adequate access provisions are made for the fire department to access the site. Incorporation of these site design measures into the design of the project will ensure that adequate fire access is provided on the site. During the public comment period on the FEIS, comments were received regarding a concern that the project could interfere with evacuation routes in the event that a wildfire occurs in surrounding rural residential areas with significant tree canopy. The FEIS preparer is aware of a fire event in 1991 in the Ponderosa residential area to the west. Such events are rare and the potential for such events stems from the combination of densely forested Ponderosa pine trees in the area and prevailing winds from the west/southwest. Because the prevailing winds that help fuel such an event are generally from the west/southwest, the logical escape route for residents from the Ponderosa residential area or from the forested hillside east of South Madison Road, if such an event were to occur again, would likely be to the north. For residents within the Ponderosa community to the west, the logical escape route would be South Dishman Mica Road either via Schafer Road or via South Bowdish Road. Both of these access points to South Dishman Mica Road are north of the Painted Hills access to South Dishman Mica Road. Therefore, future development of the Painted Hills subdivision would not interfere with either access point. For areas east and southeast of South Madison Road, the escape route would likely be South Madison Road or SR 27 farther to the east. The Painted Hills PRD will not introduce any stop-controlled intersections on South Madison that would interfere with northbound travel in the event of a fire. Furthermore, the Painted Hills PRD would not be landscaped with dense combustible landscape materials. Future buildings and infrastructure would be built to fire code and would include all required suppression features that would protect the subdivision if a fire event approached from the west, south, or east. Finally, the Painted Hills PRD will improve cross circulation between South Dishman-Mica Road and South Madison Road by providing a new east-west local circulator through the site. This will improve access to either South Madison Road or South Dishman-Mica Road and provides alternate routes of travel should fire events occur either to the east or west, where forested low density residential development exists. For these reasons, the project is not expected to have an impact on wildfire safety and may have a net benefit due to the addition of a new east-west vehicular route between South Madison Road and South Dishman-Mica Road. Public Safety It is expected that additional service calls for police, fire and emergency services will occur from future residences and businesses within the site, but these uses are not anticipated to create a significant increased demand for public safety services. Per communications with City staff, it is not anticipated that Alternative 2a would generate a significant impact to City services.12 The City regularly reviews large development proposals and, in instances where a significant new user, such as a big-box retail project, creates enough demand to warrant special adjustments in service, the City will make those adjustments to its service contract with Spokane County. It is anticipated that the gradual increase in population, employment and business activity on the site can be commensurately addressed through adjusted service levels. 12 Pers comms with Morgan Koudelka, City of Spokane Valley, January 14, 2019. Painted Hills Residential Development | Spokane Valley, Washington Page 96 Final Environmental Impact Statement Water In conjunction with the Painted Hills PRD submittal, a Certificate of Water Availability was filed with the Spokane Valley Planning Department on July 24, 2015. This certificate, signed by the site’s water purveyor, Spokane County Water District #3, acknowledges that the proposed project is consistent with the district’s Department of Health (DOH) approved water system plan. Sanitary Sewer Service to the site is provided by Spokane County Environmental Services. As noted in the July 24, 2015 certificate of sewer availability letter provided by the county, the district acknowledges that sanitary sewer service is available and can be provided to serve the project. 3.4.8.2.3 Alternative 2b – Planned Residential Development – Low Infiltration Alternative 2b would result in approximately 272 single-family residential units, 273 multi-family units, and 52 mixed-use residential units. Approximately 13,400 SF of commercial use will occur within the mixed-use buildings and approximately 9,000 SF of new retail use will occur within a newly created 92,865 SF lot located along Dishman-Mica Road. The 4,000 SF former clubhouse building will be retained in restaurant use and, as a result, would not represent a change in impact on public services. Based on the 2013 to 2017 ACS 5-Year Estimates, it is anticipated that each single-family unit would be occupied by approximately 2.5 residents, and that each of the 280 multi-family units would be occupied by approximately 2.24 residents. As such, it is expected that approximately 1,408 people would reside Alternative 2b at full project buildout. The number of employees who would work within the project would be identical to Alternative 2a. The following paragraphs summarize the anticipated effects of the uses and residents of Alternative 2b on schools, parks, fire, public safety, water, and sanitary sewer services. Schools Based on the U.S. Census Bureau ACS 5-year estimate data, approximately 15.2 percent of Spokane Valley’s population is between the ages of 5 and 17 years old. Extrapolating this number to the Painted Hills project results in an estimated 214 students who would reside within the project upon completion of Alternative 2b. While the precise cohort of elementary school, middle school, and high school students is not known, if general student population were proportionately distributed to the number of grades in elementary (six grades), middle school (three grades), and high school (four grades), it is assumed that the development of Alternative 2b would result in the following increases in student population:  Elementary School – Approximately 10 new students per year or 98 total students over the approximately 10-year buildout of the project.  Middle School – Approximately five new students per year or 46 total students over the approximately 10-year buildout of the project.  High School – Approximately seven new students per year or 70 total students over the approximately 10-year buildout of the project. Like Alternative 2a, development under Alternative 2b would provide increased school tax revenues commensurate with the demand on facilities and operations created by additional school children residing within the PRD. For example, if the current CVSD enrichment levy and bond levy were to be maintained at its Painted Hills Residential Development | Spokane Valley, Washington Page 97 Final Environmental Impact Statement current rate, it is estimated that, at full buildout of the project, approximately $472,045 per year in enrichment funding and $276,716 in bond levy funding would be generated by the project under Alternative 2b. Table 3-11: Alternative 2b. Estimated Potential Annual Levy Funds Generated at Buildout Use # Units / Acres Estimated Present Day Market Value 2022 Enrichment Levy Rate Potential Annual Enrichment Levy Funds* 2022 Bond Levy Rate Potential Annual Painted Hills Bond Levy Funds* SFR 272 $136,000,000 0.00232 $315,520 0.00136 $184,960 MFR 273 $54,600,000 0.00232 $126,672 0.00136 $74,256 COM 52 units / 3.29-A $12,867,500 0.00232 $29,853 0.00136 $17,500 Total $472,045 $276,716 Values based on $500,000 per SFR unit, $200,000 per MFR unit and $750,000 per acre for Commercial land. 2. Assumes current levy rates are maintained through project buildout. As stated in the effects discussion above for Alternative 2a, development under Alternative 2b is not anticipated to result in significant impacts to schools for the following reasons:  Student population increase from the project will occur slowly over time—approximately 22 students per year over the 10-year buildout horizon of the project—giving the district time to plan for any necessary adjustments to alter its population distribution and facilities as needed.  Prior to the 10-year buildout, it is expected that approximately two (2) years of site development would occur before any new residential structures would be constructed and any students would reside on the site. Therefore, the district would have at least one (1) to two (2) years following an approval of the Painted Hills PRD to make any initial adjustments necessary to accommodate expected near term changes in student population represented by the project.  Capital facilities revenues received by the district under current and future levies and/or other capital revenue streams will grow from the project, helping to off-set the impact on school capacity and providing the CVSD with additional means of building new facilities if needed.  The CVSD has other revenue-generating mechanisms that it could pursue if desired including the establishment of school impact fees. Fire In response to the submittal of the Painted Hills PRD application, the Spokane Valley Fire District submitted a letter, dated August 31, 2015, that provides development-specific recommendations for ensuring adequate access provisions are made for the fire department to access the site. These recommendations would not be substantially altered by the design modifications of Alternative 2b. Painted Hills Residential Development | Spokane Valley, Washington Page 98 Final Environmental Impact Statement Public Safety It is expected that additional service calls will occur from future residences and businesses within the Alternative 2b development scenario, but these uses are not anticipated to create a significant increased demand for public safety services similar to Alternative 2a. Water In conjunction with the Painted Hills PRD submittal, a Certificate of Water Availability was filed with the Spokane Valley Planning Department on July 24, 2015. This certificate, signed by the site’s water purveyor, Spokane County Water District #3, acknowledges that the proposed project is consistent with the district’s DOH approved water system plan. The project changes proposed under Alternative 2b do not alter the scale of a development in a significant manner to suggest any concerns regarding water serviceability. Sanitary Sewer Because the scale of development under Alternative 2b is approximately the same as Alternative 2a, no additional impacts on sanitary sewer service are anticipated and the certificate of service availability received for Alternative 2a represents a reasonable assurance that the Alternative 2b can be developed without significant impacts on sanitary sewer service. 3.4.8.3 Mitigation Measures There will be no significant effect on public services from Alternatives 2a and 2b. As development occurs on the site, tax revenues and utility fee revenues will increase relative to the increase in demand for public services. 3.4.8.4 Cumulative Effects There are no known cumulative effects from other on-going projects or activities that, when considered in conjunction with the action alternatives, could result in any discernible effects on public services. 3.4.9 Recreation 3.4.9.1 Affected Environment While the Painted Hills site is a former golf course, it has not been in operation since 2012 and the site is not designated for public recreation purposes. In the interim period and before site development would begin for the proposed PRD application, the applicant plans to re-open the former driving range from the golf course as an interim source of revenue from the site. It is expected that the driving range operation would cease once the PRD site is under construction. Public recreational opportunities near the Painted Hills site include two city parks, Browns Park (8.2 acres) and Castle Park (2.7 acres) (Figure 3-17), both of which are within one mile of the site. Per the City of Spokane Valley Comprehensive Plan, these parks are categorized as neighborhood parks, which are intended to generally serve residents within a half-mile radius, provide ample recreational opportunities for children, and be accessible by walking and bicycling. As noted in Figure 50 of the City’s comprehensive plan, Browns Park offers sports fields, sand volleyball courts, playgrounds, picnic areas, shelters, and restrooms, while Castle Park provides open space. In addition to these city-managed neighborhood parks, additional recreational open space areas are located at the school complex immediately northeast of the Painted Hills site, where University High school, Chester Elementary School, and Horizon Middle School are located. This complex occupies approximately 76.7 acres and includes a large outdoor recreation area with tennis courts, multiple baseball/softball fields, and soccer and football fields. Painted Hills Residential Development | Spokane Valley, Washington Page 99 Final Environmental Impact Statement Per the Parks and Recreation Master Plan 2013 Update, Table 5-2, the City has adopted a level of service standard for public parks to achieve an equivalent of 1.92 acres of park land per 1,000 residents. According to the 2013-2017 ACS 5-Year Estimates, the average household size in Spokane Valley is 2.50 people for owner- occupied households and 2.24 people for renter-occupied households13. Proposed Trails Per the City of Spokane Valley Parks and Recreation Master Plan 2013 Update, there are two trails proposed near the site (Figure 3-16). The Spokane Valley Loop – Southern Segment is a 3.5-mile segment that runs east- west from Sullivan Road to Dishman Road along 32nd Avenue. The Chester Creek Connection is a proposed one-mile segment connecting the Spokane Valley Loop at 32nd Avenue with Chester Creek. 13 U.S. Census Bureau, 2013-2017 American Community Survey 5-Year Estimates Painted Hills Residential Development | Spokane Valley, Washington Page 100 Final Environmental Impact Statement Figure 3-16: Service District Boundaries Painted Hills Residential Development | Spokane Valley, Washington Page 101 Final Environmental Impact Statement Figure 3-17: Public Recreation Opportunities Painted Hills Residential Development | Spokane Valley, Washington Page 102 Final Environmental Impact Statement 3.4.9.2 Environmental Consequences 3.4.9.2.1 Alternative 1 – No Action Under Alternative 1, no site development would occur that would generate new residents. Therefore, no additional demands would be placed on parks and recreation facilities in the community. 3.4.9.2.2 Alternative 2a – Planned Residential Development—High Infiltration Alternative 2a is anticipated to generate approximately 300 single-family residential units, 228 multi-family units, and 52 mixed-use residential units. Based on the 2013-2017 ACS 5-Year Estimates, it is anticipated that each single-family unit would be occupied by approximately 2.5 residents, and that each of the 280 multi- family units would be occupied by approximately 2.24 residents. This would result in a total population of approximately 1,377 residents upon completion of the project, which is anticipated to occur over a period of approximately 10 years or longer as the housing market dictates. Based on the City’s comprehensive plan level- of-service target of 1.92-acres of park space per 1,000 residents, the project would create demand for approximately 2.64 acres of park space in the community. As noted in the site plan included on Figure 2-5 of this document, Alternative 2a incorporates approximately 30 acres of open space, including a 10-acre park which will fulfill the recreational demands of the new development. 3.4.9.2.3 Alternative 2b – Planned Residential Development—Low Infiltration Based on the 2013 to 2017 ACS 5-Year Estimates, it is anticipated that each single-family unit would be occupied by approximately 2.5 residents, and that each of the 280 multi-family units would be occupied by approximately 2.24 residents. As such, it is expected that approximately 1,408 people would reside Alternative 2b at full project buildout. Based on the City’s comprehensive plan level-of-service target of 1.92-acres of park space per 1,000 residents, the project would create demand for approximately 2.70 acres of park space in the community. Alternative 2b incorporates approximately 30 acres of open space, including a 10-acre park which will fulfill the recreational demands of the new development. 3.4.9.3 Mitigation Measures As a Planned Residential Development, Alternative 2b must comply with SVMC Section 19.50.060, which requires at least 30 percent of the gross land area be dedicated for “common space for the use of its residents.” 3.4.9.4 Cumulative Effects The City conducts periodic reviews of its parks and recreation needs for the broader community and last updated its Parks and Recreation Master Plan in 2013. Through regular review and update of the community plan, the City anticipates and plans for necessary recreational needs throughout the community. Therefore, any cumulative effects of population growth within the broader community have been considered and integrated with the City’s parks and recreation system planning efforts. 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Painted Hills Residential Development | Spokane Valley, Washington Page 104 Final Environmental Impact Statement ACRONYMS AND ABBREVIATIONS AASHTO American Association of State Highway and Transportation Officials ACS American Community Survey ADT Average daily traffic BE Biological evaluation BFE Base flood elevation CAF Community Acknowledgment Form CE Contract entity cfs Cubic feet per second CLOMR Conditional Letter of Map Revision CM Centimeter CO Carbon monoxide CO2 Carbon dioxide CSWGP Construction Stormwater General Permit CUP Conditional Use Permit CVSD Central Valley School District CY Cubic yards DAHP Department of Archaeology and Historic Preservation DDT Dichlorodiphenyltrichloroethane DEIS Draft Environmental Impact Statement FEIS Final Environmental Impact Statement DNR Washington Department of Natural Resources DOE Washington Department of Ecology DOH Department of Health DS Determination of significance EIS Environmental Impact Statement EPA Environmental Protection Agency EWSWMM Eastern Washington Stormwater Management Manual FEMA Federal Emergency Management Agency FHA Federal Housing Authority FIRM Flood Insurance Rate Map FIS FEMA Flood Insurance Study GMA Growth Management Act HOA Homeowners’ Association IDP Inadvertent Discovery Plan IPEC Inland Pacific Engineering Company ITE Institute of Transportation Engineers KSL Per 1,000 square feet LDR Low Density Residential LID Low Impact Design LOMR FEMA Letter of Map Revision LOS Level of service LUC Land use code M&O Maintenance & Operations MPH Miles per hour NAAQS National Ambient Air Quality Standards NE Northeast NFIP National Flood Insurance Program NOx Nitrogen oxide NPDES National Pollutant Discharge Elimination System NRCS Natural Resources Conservation Service Painted Hills Residential Development | Spokane Valley, Washington Page 105 Final Environmental Impact Statement NW Northwest NWI National Wetland Inventory O3 Ozone OHWM Ordinary highwater mark O&M Operation and maintenance (manual) PAI Plateau Archaeological Investigations Pb Lead PM2.5 Particulate matter, generally 2.5 micrometers in diameter (fine) PM10 Particulate matter, generally 10 micrometers in diameter PM Particulate matter PRD Planned Residential Development RCW Revised Code of Washington ROW Right-of-way SCC Spokane County Code SE Southeast SEPA Washington State Environmental Policy Act SF Square feet SFHA Special Flood Hazard Area SFR Single-family residential SHPO State Historic Preservation Officer SO2 Sulfur dioxide SR State Route SRCAA Spokane Regional Clean Air Agency SRSM Spokane Regional Stormwater Manual SVMC Spokane Valley Municipal Code SWMMEW Stormwater Management Manual for Eastern Washington THPO Tribal Historic Preservation Officer TIA Traffic impact analysis TIP Transportation Improvement Plan TV Telescoping Video UGA Urban Growth Area USFWS U.S. Fish and Wildlife Service VOC Volatile organic compounds Vol. Volume WAC Washington Administrative Code WCE Whipple Consulting Engineers WDFW Washington Department of Fish and Wildlife WDOE Washington Department of Ecology WRIA Water Resource Inventory Area WSDOT Washington Department of Transportation Painted Hills Residential Development | Spokane Valley, Washington Page 106 Final Environmental Impact Statement LITERATURE CITED Biology, Soil & Water, Inc. 2019. Biological Evaluation, Critical Areas Report and Habitat Management Plan. February 28, 2019. Biology, Soil & Water, Inc. 2021. Biological Evaluation, Critical Areas Report and Habitat Management Plan. November 26, 2021. Biology, Soil & Water, Inc. 2022. Gustin Ditch and Triangle Pond Addendum to the Biological Evaluation for the Painted Hills PRD. June 5, 2022. CH2MHILL. 1995. Spokane County Stormwater Utility Chester Creek Watershed Plan Technical Appendices. 106950.C1.ZZ. August 7, 1995. FEMA. 2010. Flood Insurance Study. Spokane County, WA and Incorporated Areas. Study number 53063CV000A. July 6, 2010. Koudelka, Morgan. 2019. City of Spokane Valley. Personal communications. January 14, 2019. MacInnis, J.D., et al. 2009. The Spokane Valley-Rathdrum Prairie Aquifer Atlas 2009. Northwest Indian Fish Commission (NWIFC). 2015 – 2023. Statewide Washington Integrated Fish Distribution. (SWIFD) map. Retrieved from https://geo.nwifc.org/swifd/#. PBS&J. 2009. In-Depth Wetland Restoration Studies WRIA 55 &57. Spokane County division of Utilities, Public Works. Plateau Archaeological Investigations, LLC. 2018. Cultural Resource Survey of the Painted Hills Residential Development Project. April 1, 2018. Plateau Archaeological Investigations, LLC. 2022. Cultural Resource Survey for the Painted Hills Residential Development Project, Gustin Pipe Off-Site Survey Project, Spokane County Washington. March 1, 2022. Spokane Association of Realtors. 2008-2017. Comparable Statistics: Residential Site Built and Condo in Spokane County. Presented by Sabrina Jones-Schroder, J.D. Spokane-Kootenai Real Estate Research Committee. 2018. The Real Estate Report: Regional Research on Spokane, Kootenai, Bonner Counties. Volume 42, Number 1. Spring 2018. Spokane Regional Clean Air Agency. 2019. Air Pollutants of Concern. https://www.spokanecleanair.org/air- quality Spokane Regional Clean Air Agency. 2017. Spokane Air Quality Report – July 2017. https://spokanecleanair.org/wp-content/uploads/AQ-July-2017.pdf Spokane Valley Public Works Traffic Engineering. 2017. Certificate of Transportation Concurrency. US Census Bureau. American Community Survey, 5-year Estimates. US Department of Health & Human Services. 2018. TOXMAP, Environmental Health Maps. https://www.nlm.nih.gov/toxnet/index.html US Energy Information Administration. 2016. Commercial Buildings Energy Consumption Survey. Released December 2016. https://www.eia.gov/consumption/commercial/data/2012/bc/cfm/b2.php US Environmental Protection Agency. 2018. Draft Inventory of US Greenhouse Gas Emissions and Sinks: 1990 – 2016. https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-and-sinks Washington Department of Ecology. 2018. Spills Map Online Mapping Tool. https://fortress.wa.gov/ecy/coastalatlas/storymaps/spills/spills_sm.html Washington Department of Ecology. 2018. “What’s in my Neighborhood” Online Mapping Tool. https://apps.ecology.wa.gov/neighborhood/ Painted Hills Residential Development | Spokane Valley, Washington Page 107 Final Environmental Impact Statement Whipple Consulting Engineers, Inc. 2016. Traffic Impact Analysis, Painted Hills PRD. September 14, 2016. Whipple Consulting Engineers, Inc. 2018. Traffic Impact Analysis Supplemental Letter. November 21, 2018. Whipple Consulting Engineers, Inc. 2021. Truck Haul Memorandum Supplemental Letter. February 15, 2021. Painted Hills Residential Development | Spokane Valley, Washington Page 108 Final Environmental Impact Statement This page intentionally left blank.