Draft City of Kenai Hazard Mitigation Plan Photo Credit: Eagle Eye Gallery Prepared for: Prepared by: State of Alaska DMVA/DHS&EM P.O. Box 5800 JBER, Alaska 99505 November 2019 i This page was intentionally left blank. ii TABLE OF CONTENTS 1. Introduction ...................................................................................................... 1 Hazard Mitigation Planning ....................................................................... 1 Planning Requirements .............................................................................. 1 1.2.1 Local Mitigation Plans .................................................................... 1 Grant Programs with Mitigation Plan Requirements ................................. 1 1.3.1 Hazard Mitigation Assistance (HMA) Unified Programs ................. 2 HMP Description ........................................................................................ 3 2. Prerequisites ..................................................................................................... 5 Adoption by City Council and Supporting Documentation ........................ 5 3. Community Description .................................................................................... 6 Location ..................................................................................................... 6 History ....................................................................................................... 6 Demographics ............................................................................................ 7 Economy .................................................................................................... 8 4. Planning Process ............................................................................................... 9 Overview of Planning Process .................................................................... 9 Hazard Mitigation Planning Team ............................................................ 10 Public Involvement & Opportunity for Interested Parties to Participate ............................................................................................... 10 Incorporation of Existing Plans and Other Relevant Information ............. 11 5. Hazard Profiles ................................................................................................ 13 Overview of a Hazard Analysis ................................................................. 13 Hazard Identification and Screening ........................................................ 13 Hazard Profile .......................................................................................... 14 5.3.1 Changes in the Cryosphere .......................................................... 15 5.3.2 Earthquake ................................................................................... 17 5.3.3 Flood and Erosion ........................................................................ 24 5.3.4 Volcanoes and Ashfalls ................................................................. 34 5.3.5 Severe Weather ........................................................................... 37 5.3.6 Wildfire and Conflagration Fire .................................................... 42 6. Vulnerability Analysis ..................................................................................... 49 Overview of a Vulnerability Analysis ........................................................ 49 iii Current Asset Exposure Analysis .............................................................. 49 6.2.1 Asset Inventory ............................................................................ 49 7. Mitigation Strategy ......................................................................................... 57 Developing Mitigation Goals .................................................................... 57 Identifying Mitigation Actions .................................................................. 58 Evaluating and Prioritizing Mitigation Actions ......................................... 58 Implementing a Mitigation Action Plan ................................................... 61 8. Plan Maintenance ........................................................................................... 66 Monitoring, Evaluating, and Updating the HMP ...................................... 66 Implementation Through Existing Planning Mechanisms ........................ 67 Continued Public Involvement ................................................................. 71 Potential Funding Resources ................................................................... 71 9. References ...................................................................................................... 77 iv Tables Table 1. Hazard Mitigation Planning Team ................................................................................................. 10 Table 2. Public Involvement Mechanisms................................................................................................... 10 Table 3. Identification and Screening of Hazards ....................................................................................... 14 Table 4. Perceived Shaking, Potential Damage, and Peak Ground Acceleration ........................................ 19 Table 5. Historical Earthquakes within a 50‐Mile Radius of the Approximate Center of the City .............. 20 Table 6. Hazus Earthquake Results for M7.1 and M9.2 Earthquakes in the City of Kenai ......................... 22 Table 7. FEMA RiskMap Identified Areas of Mitigation Interest ................................................................ 23 Table 8. Moderate‐ and High‐Code Buildings in the City of Kenai .............................................................. 23 Table 9. Historical Wildland Fires ................................................................................................................ 45 Table 10. Estimated Population and Building Inventory ............................................................................ 50 Table 11. Alaska’s Critical Infrastructure .................................................................................................... 50 Table 12. Kenai’s Critical Facilities .............................................................................................................. 53 Table 13. Mitigation Goals .......................................................................................................................... 58 Table 14. Mitigation Goals and Potential Actions ....................................................................................... 59 Table 15. Evaluation Criteria for Mitigation Actions ................................................................................... 60 Table 16. City Mitigation Action Plan .......................................................................................................... 62 Table 17. Regulatory Tools .......................................................................................................................... 69 Table 18. Administrative and Technical Resources .................................................................................... 69 Table 19. Financial Resources for Hazard Mitigation ................................................................................. 70 Figures Figure 1. Kenai’s Historic Population ............................................................................................................ 7 Figure 2. Active and Potentially Active Faults in Alaska.............................................................................. 22 Figure 3. State of Alaska Earthquake Probability ........................................................................................ 24 Figure 4. Erosion Mechanism Schematic .................................................................................................... 27 Figure 5. Kenai Bluffs Location .................................................................................................................... 27 Figure 6. Kenai Bluffs Eroded Surface ......................................................................................................... 28 Figure 7. Storm Event at Kenai Bluffs.......................................................................................................... 28 Figure 8. Kenai Bluffs Erosion ..................................................................................................................... 31 Figure 9. Kenai Coastal Erosion ................................................................................................................... 32 Figure 10. Regional Volcanos ...................................................................................................................... 35 Figure 11. Areas Affected by Ash Falls ........................................................................................................ 36 Figure 12. Alaska Fire Management Options .............................................................................................. 44 Figure 13. Kenai Wildland Fire History ........................................................................................................ 47 Figure 14. City’s Wildland Fire Risk ............................................................................................................. 48 Figure 15. Critical Facilities Locations ........................................................................................................