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Risk Analysis and Damage Assessment for Flood Prone Areas in Washington DC

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Risk Analysis and Damage Assessment for Flood Prone Areas in Washington DC ABSTRACT Title of Document: Risk Analysis and Damage Assessment For Flood Prone Areas in Washington DC Arian Lessani, Master of Science, 2011 Directed By: Dr. Gregory B. Baecher, Professor Civil and Environmental Engineering This thesis presents a loss estimation method regarding areas of District of Columbia susceptible to flooding, specifically the Southwest quadrant, the National Mall, and Federal Triangle. This thesis develops data for input to a flood model that considers parameters such as detailed digital elevation data, global warming potential, and storm surge for a category IV hurricane. The main goal of this study is to employ a standard method for estimating flooding damages in Washington by supplying combination of the mentioned parameters to the HAZUS-MH 2.0 program. The results of this research is useful for planning purposes, such as reducing natural hazard losses and preparing emergency response and recovery. It is predicted that in the projected storm surge flood more than 1500 buildings would be damaged and about ten thousand people would seek temporary refuge in public shelters. The estimate of total loss for flooding is approximately $1,300 million dollars. Key Words: Risk Analysis, Loss estimation, Potential Flood Risk in Washington DC RISK ANALYSIS AND DAMAGE ASSESSMENT FOR FLOOD PRONE AREAS IN WASHINGTON DC By Arian Lessani Thesis submitted to the Faculty of the Graduate School of the University of Maryland, College Park, in partial fulfillment of the requirements for the degree of Master of Science 2011 Advisory Committee: Professor Gregory B. Baecher, Chair Research Professor Gerald E. Galloway Senior Research Engineer Lewis E. Link Associate Professor Kaye L. Brubaker © Copyright by Arian Lessani 2011 i Dedication To my parents and my brother for their unconditional help and support ii Acknowledgements I would like to express my sincere gratitude to my advisor Prof. Gregory Baecher, for his invaluable support and commitment to the completion of this research. I would like to thank Dr. Galloway for his invaluable support, especially in delivering information and database and connecting me to experts in the field of study. In addition, I would like to thank Dr. Link and Dr. Brubaker for sharing their knowledge and for their willingness to support me. I would like to thank all of the organizations and personnel who assisted me in conducting my research, and overcome my research challenges. iii Table of Contents Dedication ...................................................................................................................... ii Acknowledgements .......................................................................................................... iii Table of Contents ............................................................................................................. iv List of Figures ................................................................................................................ viii List of Tables .................................................................................................................... ix 1. Introduction ................................................................................................................ 1 1.1. Research Objective .......................................................................................... 1 1.2. Washington DC Hydrologic Concerns ............................................................ 2 1.3. Flooding Types for DC ................................................................................... 3 1.4. Global Warming .............................................................................................. 4 2. Literature Review ...................................................................................................... 7 2.1. Strom surge hazard .......................................................................................... 7 2.1.1. Storm Surge ........................................................................................... 8 2.1.2. SLOSH Model ....................................................................................... 9 2.1.3. Maximum Envelopes of Water (MEOWS) ......................................... 10 2.1.4. The Saffir-Simpson Hurricane Wind Scale ......................................... 11 2.1.5. Probability and Return periods of Storm Surge in Washington DC ... 14 2.1.6. GIS Storm Surge Mapping .................................................................. 15 2.2. FEMA Flood Maps ........................................................................................... 16 2.1.7. Flood Insurance Study ................................................................................... 16 2.1.8. Flood Insurance Rate Map (FIRM) ............................................................... 18 2.1.9. Return Period ................................................................................................. 19 3. History of Flooding in Washington DC ................................................................... 22 3.1. District of Columbia ...................................................................................... 22 3.2. Hurricane of 1878 .......................................................................................... 23 3.3. Flood of 1889 ................................................................................................ 23 3.4. Hurricane of 1893 .......................................................................................... 25 3.5. Hurricane of 1896 .......................................................................................... 25 3.6. Floods of 1924 ............................................................................................... 26 3.7. Chesapeake-Potomac Hurricane; 1933 ......................................................... 26 3.8. Flood of 1936 ................................................................................................ 27 3.9. Flood of 1937 ................................................................................................ 27 3.10. Flood of 1942 ................................................................................................ 28 3.11. Hurricane Able; 1952 .................................................................................... 29 3.12. Hurricane Hazel; 1954 .................................................................................. 29 3.13. Hurricane CONNIE; 1955 ............................................................................. 30 iv 3.14. Hurricane Agnes; 1972 .................................................................................. 31 3.15. Hurricane David; 1979 .................................................................................. 32 3.16. Hurricane Juan; November 4-7, 1985 ........................................................... 33 3.17. Flood of 1988 ................................................................................................ 33 3.18. Flood of 1996 ................................................................................................ 33 3.19. Hurricane Fran; 1996 .................................................................................... 33 3.20. Hurricane Floyd; 1999 .................................................................................. 34 3.21. Flood of 2001 ................................................................................................ 35 3.22. Hurricane Isabel; 2003 .................................................................................. 35 3.23. Flood of 2006 ................................................................................................ 36 4. Past Flood Protection Measures ............................................................................... 40 4.1. Permanent portion of the National Mall Levee ............................................. 40 4.2. Temporary Closures of the National Mall Levee .......................................... 41 4.2.1. 17th Street Floodwall .......................................................................... 43 4.2.2. Fort McNair Closure ............................................................................ 46 4.2.3. 23rd Street Closure ............................................................................... 46 4.3. Anacostia River ............................................................................................. 47 4.3.1. Anacostia sedimentation ...................................................................... 48 4.3.2. Anacostia dredging .............................................................................. 48 4.4. Washington DC Emergency Flood Procedures ............................................. 50 4.5. Drainage Flooding ......................................................................................... 52 4.6. Tidal Flooding Measures ............................................................................... 53 5. Approach and Framework of the research ............................................................... 55 5.1. Goal ............................................................................................................... 55 5.2. Software Applications ................................................................................... 55 5.3. Standardization .............................................................................................. 56 5.4. Inputs of Method ..........................................................................................
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