KITSAP COUNTY Climate Change Resiliency Assessment JUNE 2020 | FINAL REPORT KITSAP COUNTY CLIMATE CHANGE RESILIENCY ASSESSMENT JUNE 2020 Kitsap County Climate Change Resiliency Assessment List of Figures ..................................................................................................................................... 4 List of Tables ...................................................................................................................................... 6 List of Acronyms................................................................................................................................. 7 Executive Summary ............................................................................................................................ 8 Chapter 1. Introduction .................................................................................................................... 11 Chapter 2. Climate Change Overview ................................................................................................ 23 Climate Scenarios ........................................................................................................................................... 27 Sea Level Rise .................................................................................................................................................. 27 Marine Water Temperature ............................................................................................................................ 30 Ocean Acidification and Dissolved Oxygen ..................................................................................................... 31 Temperature Trends, Extreme Heat, and Freeze-Free Days ............................................................................ 33 Precipitation.................................................................................................................................................... 36 Streamflow ..................................................................................................................................................... 39 Stream Temperature ....................................................................................................................................... 39 Wildfires .......................................................................................................................................................... 40 Chapter 3. Public Health ................................................................................................................... 42 Finding 1: Heat-related Illnesses ..................................................................................................................... 44 Finding 2: Respiratory Illnesses....................................................................................................................... 45 Finding 3: Acute Injuries from Extreme Weather ........................................................................................... 47 Finding 4: Vector-borne Diseases ................................................................................................................... 49 Finding 5: Food Security ................................................................................................................................. 50 Finding 6: Mental Health and Wellbeing ........................................................................................................ 51 Finding 7: Communities of Concern ............................................................................................................... 53 Finding 8: Health and Social Safety Net .......................................................................................................... 54 Chapter 4. Economy ......................................................................................................................... 55 Finding 1: Property Values and Buildable Land .............................................................................................. 58 Finding 2: Shifts in Business Opportunities .................................................................................................... 61 Finding 3: Energy Demand and Utilities ......................................................................................................... 64 Finding 4: Economic Costs of Climate Change ................................................................................................ 65 Chapter 5. Cultural Resources ........................................................................................................... 70 Finding 1: Historic and Archaeological Sites ................................................................................................... 71 Finding 2: Recreation ...................................................................................................................................... 73 Finding 3: Tribal Cultural, Ceremonial, and Harvesting Sites .......................................................................... 77 Chapter 6. Public Infrastructure ........................................................................................................ 79 Finding 1: Transportation ................................................................................................................................ 81 Finding 2: Water, Wastewater, and Stormwater ............................................................................................. 84 Finding 3: Coastal Infrastructure..................................................................................................................... 87 Finding 4: Urban Infrastructure ...................................................................................................................... 89 Finding 5: Rural Infrastructure ........................................................................................................................ 91 Finding 6: Power and Energy .......................................................................................................................... 92 2 KITSAP COUNTY CLIMATE CHANGE RESILIENCY ASSESSMENT JUNE 2020 Chapter 7. Land Use and Development ............................................................................................. 93 Finding 1: Land Use Affects Local Climate Impacts ......................................................................................... 94 Finding 2: Climate Impacts on Land Use and Cover........................................................................................ 97 Finding 3: Adaptive Capacity ........................................................................................................................ 100 Chapter 8. Agriculture .................................................................................................................... 101 Finding 1: Crops ............................................................................................................................................ 103 Finding 2: Pests ............................................................................................................................................. 105 Finding 3: Flood Risks.................................................................................................................................... 106 Finding 4: Agricultural Economies and Livelihoods ...................................................................................... 107 Finding 5: Adaptive Capacity ........................................................................................................................ 108 Chapter 9. Local Government Finance ............................................................................................. 109 Finding 1: Insurance ...................................................................................................................................... 110 Finding 2: Municipal Bonds........................................................................................................................... 114 Finding 3: Tax Revenue ................................................................................................................................. 118 Chapter 10. Geologic & Natural Hazards ......................................................................................... 122 Finding 1: Landslides and Sediment Processes ............................................................................................. 123 Finding 2: Bluff Erosion ................................................................................................................................. 126 Finding 3: Storm Surge and Coastal Flooding ............................................................................................... 129 Chapter 11. Hydrology and Hydrogeology ....................................................................................... 133 Finding 1: Hydrologic Changes ...................................................................................................................... 135 Finding 2: Stream and Riverine Flooding ...................................................................................................... 137 Finding 3: Hydropower ................................................................................................................................. 138 Finding 4: Irrigated Agriculture ....................................................................................................................