Rock Island County Multi-Jurisdictional Local Hazard Mitigation Plan Rock Island County Rock Island County Multi-Jurisdictional Local Hazard Mitigation Plan Approved by FEMA April 6, 2009 This document was prepared by: Table of Contents Section Page Executive Summary ....................................................................................................................... i I. Prerequisites .......................................................................................................................1 Adoption by the Local Governing Body ..............................................................................1 FEMA Approval ..................................................................................................................1 Multi-Jurisdictional Plan Adoption......................................................................................3 Multi-Jurisdictional Planning Participation .........................................................................3 Planning Area Location Map ...............................................................................................4 II. Planning Process ................................................................................................................6 Public Participation ..............................................................................................................7 Review of Existing Plans, Studies, Reports, and Technical Information ............................8 III. Risk Assessment ...............................................................................................................10 Identifying hazards.............................................................................................................10 Profiling Hazards ...............................................................................................................11 Prioritizing Hazards ...........................................................................................................12 Hazard Profiles...................................................................................................................16 Floodplain Information (Rock Island County and Incorporated Municipalities) ....... 43 Magnitude of Flood Effects ........................................................................................ 48 Human-Caused Hazards.....................................................................................................71 Assessing Vulnerability: Overview ..................................................................................76 Community Profile: Rock Island County, Illinois ..................................................... 76 Local History .............................................................................................................. 80 Assessing Vulnerability: Identifying Structures ................................................................86 Determining Community Assets ................................................................................. 86 Critical Facilities ......................................................................................................... 89 Assessing Vulnerability: Estimating Potential Losses ......................................................91 Assessing Vulnerability: Analyzing Development Trends ...............................................91 Multi-Jurisdictional Risk Assessment................................................................................97 Andalusia .................................................................................................................... 97 Carbon Cliff ................................................................................................................ 99 Coal Valley ............................................................................................................... 101 Cordova ..................................................................................................................... 102 East Moline ............................................................................................................... 104 Hampton .................................................................................................................... 106 Hillsdale .................................................................................................................... 108 Milan ....................................................................................................................... 109 Table of Contents (continued) Section Page Moline ....................................................................................................................... 111 Oak Grove ................................................................................................................. 114 Port Byron ................................................................................................................. 116 Rapids City................................................................................................................ 117 Reynolds ................................................................................................................... 119 Rock Island ............................................................................................................... 121 Rock Island County (Unincorporated) ...................................................................... 123 Silvis ....................................................................................................................... 124 IV. Mitigation Strategy ........................................................................................................127 Local Hazard Mitigation Goals ........................................................................................127 Identification and Analysis of Mitigation Actions ...........................................................128 Range of mitigation measures ..........................................................................................128 Evaluation of Alternative Mitigation Actions ..................................................................129 Multi-Jurisdiction Mitigation Actions .............................................................................138 V. Plan Maintenance Process .............................................................................................144 Monitoring the Plan .........................................................................................................144 Evaluating the Plan ..........................................................................................................144 Updating the Plan .............................................................................................................144 Incorporation into Existing Planning Mechanisms ..........................................................145 Continued Public Involvement ........................................................................................147 Appendices ......................................................................................................................................1 Appendix I-1 ...................................................................................................................................1 Correspondence from FEMA Regarding Plan Approval .....................................................1 Appendix I-2 ...................................................................................................................................5 Sample Resolution ...............................................................................................................5 Appendix I-3 ...................................................................................................................................6 Copies of Signed Multi-Jurisdiction Adoptions ..................................................................6 Appendix II-1 ...............................................................................................................................22 Planning Staff.....................................................................................................................22 Steering Committee (Primary Contacts in Bold) ...............................................................22 Appendix II-2 ...............................................................................................................................24 Multi-Jurisdictional Planning Participation .......................................................................24 Appendix II-3 ...............................................................................................................................26 Appendix II-4 ...............................................................................................................................29 Table of Contents (continued) Section Page Appendix II-5 ...............................................................................................................................30 Advisory Group Contacts ..................................................................................................30 Appendix II-6 ...............................................................................................................................31 Rock Island County Pre-Disaster Mitigation (PDM) Planning .........................................31 Appendix II-7 - A .........................................................................................................................32