Lambert Engineers, LLC Sewerage and Water Board of New Orleans Local Hazard Mitigation Plan – March 2010 Sewerage and Water Board of New Orleans Local Hazard Mitigation Plan March 2010 DRAFT PreparedDRAFT by Lambert Engineers, LLC DRAFT OPEN FOR PUBLIC COMMENT 3/25/10 Lambert Engineers, LLC Sewerage and Water Board of New Orleans Local Hazard Mitigation Plan This page intentionally left blank DRAFT Page 2 of 169 For Official Use Only Draft 03/22/2010 no distribution DRAFT OPEN FOR PUBLIC COMMENT 3/25/10 Lambert Engineers, LLC Sewerage and Water Board of New Orleans Local Hazard Mitigation Plan Table of Contents RECORD OF CHANGES ............................................................................................................................................ 9 1. INTRODUCTION ........................................................................................................................................... 11 1.1. WHAT IS A HAZARD MITIGATION PLAN ? .............................................................................................................. 12 1.2. BENEFITS OF MITIGATION PLANNING .................................................................................................................. 13 1.3. REGULATORY REQUIREMENTS ............................................................................................................................ 15 2. ABOUT THE SEWERAGE AND WATER BOARD OF NEW ORLEANS ................................................................. 17 2.1. WATER SYSTEM .............................................................................................................................................. 18 2.2. SEWERAGE SYSTEM ......................................................................................................................................... 21 2.2.1. Sewerage System Upgrades .............................................................................................................. 22 2.2.2. Sewerage System Facts ..................................................................................................................... 22 2.3. DRAINAGE SYSTEM .......................................................................................................................................... 26 2.4. PURPOSE AND SCOPE ....................................................................................................................................... 28 2.5. PARTICIPATING JURISDICTIONS ........................................................................................................................... 29 3. PLANNING PROCESS .................................................................................................................................... 31 3.1. PLANNING PROCESS NARRATIVE ........................................................................................................................ 31 3.2. PLANNING TEAM MEMBERS .............................................................................................................................. 33 3.3. DESCRIPTION OF THE PLANNING PROCESS ............................................................................................................. 34 3.4. COORDINATION WITH AGENCIES ......................................................................................................................... 35 3.5. PLANNING MEETINGS ....................................................................................................................................... 35 3.5.1. Meeting Schedule .............................................................................................................................. 35 3.6. PUBLIC OUTREACH .......................................................................................................................................... 36 3.6.1. Pre-Draft Phase Public Meeting ........................................................................................................ 36 3.6.2. Pre-Adoption Public Meeting ............................................................................................................. 37 3.7. INVOLVING KEY STAKEHOLDERS ......................................................................................................................... 37 3.8. REVIEW AND INCORPORATION OF EXISTING INFORMATION ...................................................................................... 37 3.9. ADOPTION ..................................................................................................................................................... 37 4. HAZARD VULNERABILITY ASSESSMENT ....................................................................................................... 38 4.1. HAZARD IDENTIFICATION ................................DRAFT.................................................................................................. 38 4.1.1. Identified Hazards.............................................................................................................................. 40 4.1.2. Hazards considered, but eliminated .................................................................................................. 40 4.1.3. Special Note for Cyber Attack, Civil Unrest and Terrorism Hazards .................................................. 45 4.1.1. Critical Infrastructure ........................................................................................................................ 45 4.2. INCLUDED HAZARDS ........................................................................................................................................ 46 4.2.1. Hazards identified for this Plan ......................................................................................................... 47 4.3. HAZARD PROFILES ........................................................................................................................................... 48 4.3.1. Flood .................................................................................................................................................. 49 4.3.2. Hailstorm ........................................................................................................................................... 56 4.3.3. Hazardous Materials ......................................................................................................................... 59 4.3.4. Hurricane / Tropical Cyclone / Coastal Storms .................................................................................. 63 Page 3 of 169 For Official Use Only DRAFT OPEN FOR PUBLIC COMMENT 3/25/10 Lambert Engineers, LLC Sewerage and Water Board of New Orleans Local Hazard Mitigation Plan – March 2010 4.3.5. Levee Failure ...................................................................................................................................... 73 4.3.6. Lightning/Thunderstorms/Severe Storms .......................................................................................... 80 4.3.7. Saltwater Intrusion ............................................................................................................................ 84 4.3.8. Severe Cold / Severe Heat / Winter Storms ....................................................................................... 86 4.3.9. Storm Surge ....................................................................................................................................... 90 4.3.10. Subsidence (Expansive Soils) .............................................................................................................. 94 4.3.11. Tornados .......................................................................................................................................... 100 5. ASSESSING VULNERABILITY ....................................................................................................................... 105 5.1. CRITICAL FACILITY ANALYSIS ............................................................................................................................ 105 5.2. VULNERABILITY SUMMARY .............................................................................................................................. 106 5.2.1. Systemic Notes – Valuation Data .................................................................................................... 109 5.3. NFIP COMPLIANCE ....................................................................................................................................... 111 5.4. LAND USE TRENDS ........................................................................................................................................ 111 5.4.1. Population ...................................................................................................................................... 111 5.4.2. Land Use .......................................................................................................................................... 111 5.4.3. S&WB and Land Use Trends ............................................................................................................ 112 6. MITIGATION STRATEGY ............................................................................................................................. 113 6.1. GOALS AND OBJECTIVES ................................................................................................................................. 113 6.1.1. Goals ...............................................................................................................................................