BERKELEY COUNTY DRAFT HAZARD MITIGATION PLAN October 8, 2019 Berkeley-Charleston-Dorchester Council of Governments Update Table of Contents EXECUTIVE SUMMARY ............................................................................................................ 1 INTRODUCTION .......................................................................................................................... 2 Hazard Mitigation Plan Background .......................................................................................... 2 Purpose of Hazard Mitigation Planning ...................................................................................... 3 Related Planning Efforts in the Region ...................................................................................... 5 Hazard Mitigation Plan Scope .................................................................................................... 6 Participants in the Planning Process ........................................................................................... 7 Public Participation ..................................................................................................................... 8 Planning Process ....................................................................................................................... 10 Step 1 .................................................................................................................................... 10 Step 2 .................................................................................................................................... 10 Step 3 .................................................................................................................................... 11 Step 4 .................................................................................................................................... 11 Step 5 .................................................................................................................................... 11 Project Timeline ........................................................................................................................ 12 Organize Resources .................................................................................................................. 12 Assess Risks and Develop a Mitigation Plan:........................................................................... 12 Community Goals and Objectives ............................................................................................ 13 Goal 1 .................................................................................................................................... 13 Goal 2 .................................................................................................................................... 14 Goal 3 .................................................................................................................................... 14 Goal 4 .................................................................................................................................... 14 Goal 5 .................................................................................................................................... 15 Goal 6 .................................................................................................................................... 15 Goal 7 .................................................................................................................................... 15 Goal 8 .................................................................................................................................... 16 Goal 9 .................................................................................................................................... 16 Goal 10 .................................................................................................................................. 16 Goal 11 .................................................................................................................................. 16 Mitigation Action Plans ............................................................................................................ 17 Types ..................................................................................................................................... 17 Action Plan for Berkeley County, SC ........................................................................................... 22 Action Plan for the Town of Bonneau, SC ................................................................................... 36 Action Plan for the City of Goose Creek, SC ............................................................................... 38 Action Plan for the City of Hanahan, SC ...................................................................................... 40 Action Plan for the Town of Jamestown, SC ................................................................................ 44 Action Plan for the Town of Moncks Corner, SC ........................................................................ 45 Action Plan for the Town of St. Stephen, SC ............................................................................... 49 IMPLEMENTATION ................................................................................................................... 50 Process ...................................................................................................................................... 50 Local Planning Mechanisms ..................................................................................................... 50 Funding Sources........................................................................................................................ 51 Local Funding Sources ............................................................................................................. 53 1 MONITORING, EVALUATION AND UPDATING .................................................................. 54 Timeframes ............................................................................................................................... 54 Three-Year Plan Review ....................................................................................................... 54 Five-Year Update .................................................................................................................. 54 Incorporation of Local Planning Mechanisms .......................................................................... 55 Continuing Public Participation ............................................................................................ 56 Plan Amendments ..................................................................................................................... 57 HAZARD IDENTIFICATION AND ANALYSIS ...................................................................... 58 Introduction ............................................................................................................................... 58 Potential Hazards ...................................................................................................................... 58 Hazard Probability .................................................................................................................... 60 Flooding ................................................................................................................................ 61 Hurricanes and Tropical Storms ........................................................................................... 67 Tornadoes .............................................................................................................................. 74 Winter Storms ....................................................................................................................... 77 Thunderstorms ...................................................................................................................... 78 Hail ........................................................................................................................................ 78 Wildfires ............................................................................................................................... 80 Drought ................................................................................................................................. 82 Earthquake ............................................................................................................................ 84 Liquefaction .......................................................................................................................... 89 Landslides ............................................................................................................................. 91 Tsunamis ............................................................................................................................... 91 Dam Failure .......................................................................................................................... 92 Hazardous Materials ............................................................................................................. 94 VULNERABILITY ASSESSMENT ............................................................................................ 99 Introduction 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