11/29/2005 CITY OF BAYTOWN FLOOD MITIGATION PLAN PREPARED BY CITY OF BAYTOWN FLOODPLAIN MITIGATION PLANNING COMMITTEE HALFF ASSOCIATES, INC. February 2005 2/28/05 TABLE OF CONTENTS Table of Contents............................................................................................................................ 2 Executive Summary........................................................................................................................ 4 Introduction................................................................................................................................... 16 Purpose.......................................................................................................................................... 17 Community Specific Information ................................................................................................. 18 History of Flooding within the City of Baytown.......................................................................... 19 1. How this Plan was prepared...................................................................................................... 22 1.1 Organize to Prepare the Plan............................................................................................. 22 1.2 Flood Mitigation Planning Schedule ................................................................................ 23 1.3 Public Meeting.................................................................................................................. 25 1.4 Mitigation Plan Questionnaire .......................................................................................... 26 1.5 Coordination with Other Agencies ................................................................................... 27 1.6 Meeting with Other Agencies to review common problems ............................................ 28 1.7 Establishing Goals ............................................................................................................ 28 1.8 Distribution of Draft Action Plan ..................................................................................... 28 2. Assess the Hazard ..................................................................................................................... 30 2.1 Map of Known Floodprone Areas .................................................................................... 30 2.2 Known Hazards................................................................................................................. 37 2.3 Flood Events ..................................................................................................................... 42 2.4 Storm Surge Hazards ........................................................................................................ 43 2.5 Subsidence ........................................................................................................................ 44 2.6 Elevation Reference Marks............................................................................................... 51 3. Assess the Problem ................................................................................................................... 54 3.1 Discussion of the number and types of buidlings subject to hazards ............................... 54 3.2 Structures that have received flood insurance claims....................................................... 54 3.3 Plan and procedures for warning and evacuation ............................................................. 55 3.4 Critical Facilities............................................................................................................... 61 3.5 Wetlands, Riparian Area, and Sensitive Areas ................................................................. 62 3.6 Capital Improvement Projects........................................................................................... 63 3.7 Impact of Flooding............................................................................................................ 69 4. Goals ......................................................................................................................................... 69 5. Review of Possible Activities ................................................................................................... 71 5.1 Preventive Activities......................................................................................................... 71 5.2 Property Protection ........................................................................................................... 72 5.3 Natural Resource Protection ............................................................................................. 74 5.4 Emergency Services.......................................................................................................... 75 5.5 Structural Projects............................................................................................................. 75 5.6 Public Information ............................................................................................................ 76 Page 2 City of Baytown, Texas Flood Mitigation Plan 2/28/05 6. Draft Action Plan ...................................................................................................................... 78 7. Adopt the Plan........................................................................................................................... 87 8. Implementation, Evaluation, and Revision of the Plan............................................................. 88 8.1 Procedure for implementing, evaluating, and revising the plan ....................................... 88 8.2 Implementation, evaluation and revision of the plan........................................................ 88 Attachment A - List of Acronyms Attachment B - Public Notification of Public Meeting Attachment C - Questionnaire and News Articles Attachment D - Map Needs Assessment Form Attachment E - City of Baytown Flood Insurance Rate Maps Page 3 City of Baytown, Texas Flood Mitigation Plan 2/28/05 EXECUTIVE SUMMARY Utilizing Flood Mitigation Assistance Program (FMA) funding from the Texas Water Development Board (TWDB), the City of Baytown committed to developing a Flood Mitigation Plan to address flooding concerns within the community. The City selected Halff Associates, Inc., as a planning consultant to assist in the preparation of the Flood Mitigation Plan. The City of Baytown is vulnerable to several natural and technological hazards that have been addressed in the Harris County All Hazards Mitigation Plan prepared by the Houston Galveston Area Council with Hazard Mitigation Grant Program (HMGP) funding administered by the Governors Division of Emergency Management (TxDEM). The Harris County All Hazards Plan was prepared to meet the requirements of the Disaster Mitigation Act of 2000 and to qualify Harris County and all participating communities that include the City of Baytown, for future Hazard Mitigation Grant Program (HMGP) funding. In order to address the specific flood hazards faced, the City of Baytown has also developed a Flood Mitigation Plan to satisfy the requirements of both the Flood Mitigation Assistance Program as administered through the TWDB and the Community Rating System (CRS) program as administered through the Federal Emergency Management Agency (FEMA). Mitigation is characterized as a long-term, ongoing process. This plan seeks to address all flood hazards within the City of Baytown, in both Harris and Chambers Counties. It provides general guidance related to various flood hazards within the community and an overview of numerous mitigation efforts undertaken by the community. In addition, the plan identifies potential problematic conditions and outlines corrective actions that the City will undertake to remedy identified problems. Planning and implementation actions will be identified that are applicable to both pre-disaster and post disaster situations. A Flood Mitigation Plan is more than just another planning document. It is a dynamic record of the community’s recognition of its vulnerability to flood hazards, determination of the risks associated with flood effects, and commitment to reducing the long-term consequence of flooding. The Flood Mitigation Plan outlines the mitigation goals within the community, identifies risk reduction strategies for hazards that threaten the area, and discusses the ongoing risk reduction activities accomplished within the jurisdiction. The City of Baytown Flood Mitigation Plan was developed by following the ten (10) step planning process outlined in the FEMA CRS Coordinators Manual as Floodplain Management Planning Criteria; the process was further expanded to include FMA planning requirements. TWDB and FEMA approval of the City of Baytown Flood Mitigation Plan qualifies the City of Baytown to receive federal funding through the FMA program for acquisition, relocation, and/or elevation of flood damaged properties. The City of Baytown participates in the National Flood Insurance Program (NFIP); this allows flood insurance to be available throughout the community. FEMA has classified the City of Baytown as a Class Seven (7) within the CRS Program. This classification recognizes the City of Baytown’s Floodplain Management Program as exceeding the basic requirements for Page 4 City of Baytown, Texas Flood Mitigation Plan 2/28/05 participation in the NFIP. The Class 7 rating reduces flood insurance premiums within the