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Floodplain Management 2050 Are Gilbert’s Adjustment Factors Sufficient? PowerPoint Presentation
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Floodplain Management 2050 Are Gilbert’s Adjustment Factors Sufficient?

Floodplain Management 2050 Are Gilbert’s Adjustment Factors Sufficient?

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Floodplain Management 2050 Are Gilbert’s Adjustment Factors Sufficient?

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  1. Floodplain Management 2050 Are Gilbert’s Adjustment Factors Sufficient? Larry A. Larson, P.E. CFM Association of State Floodplain Managers

  2. Overview • Early approaches to Flood losses • The Foundation for change in last 60 yrs- Human Adjustments To Floods • Trends/drivers of change in 2050 • Strategies to adapt in 2050 • A Charge to Forum participants

  3. Early approaches to Flood lossesEngineering solutions • 1850-Congress asked the Corps to study flood control on lower Miss. River • 1917-$45 M for levees on Lower Miss. • 1927 flood affected social change • 1936 FCA—Federal lead in flood control • Billions spent on structural works • Damages continued to mount

  4. A Shift in Managing Floods • Engineering had some success, but long term losses continued and risk increased • Contributions to losses from external factors such as land use, population, etc • Gilbert’s dissertation suggests adjusting human behavior, not engineering nature

  5. Defined what was later called Floodplain Management Introduced the human element Impact Responsibility Need to Adjust Importance of White’s Work

  6. Human Adjustments to Floods • Elevation • Flood Abatement (Watershed management) • Flood Protection (Structural flood control) • Emergency Measures • Structural Adjustments (adjustments to buildings and infrastructure) • Land Use • Public Relief • Insurance (Adapted from Gilbert F. White- 1942 Dissertation)

  7. Experiences of the last 60 years? • NFIP biggest added tool • Quid pro quo flood insurance—land use • Over 20,000 communities participate by • Regulating land use in floodplain • Keeping floodways open • Elevating structures in flood fringe • $1.2 billion/yr in reduced damage

  8. Experiences of the last 60 years? • Heavy top down approaches by federal agencies to “stop” flooding continued • Continued building structural projects • Spent over $35 billion on projects • Dams, levees and channels

  9. Experiences of the last 60 years? Flooding Still Increasing- • More watershed runoff • Loss of floodplain storage • Floodwater transfer • Current process looks at Development in floodplain, but not impacts of all development in watershed (NAI)

  10. Results? • Those living at risk pay part of the cost of living at risk in flood hazard areas • Over 5 million flood insurance policies that help property owners recover • Structural projects cost shared But: • Damages still increasing, albeit at a slower rate

  11. Factors affecting human adjustment approaches • Population and development patterns • Climate variation • Human and Social factors • Environmental/resource • Economy and government budgets • Institutional programs and policies • Financial incentives/disincentives

  12. 100 Million more people by 2050 How does that impact: Coastal zones? Failure zones of Levees and dams? Arid region Hazards? Natural and Beneficial resources in hazard areas Infrastructure needs? Transportation and water Population

  13. Increased Housing • Housing Trends • Condo and High Rise Development, thus increased density • Affordability- 40 year or longer mortgages • Increased percentage of personal balance sheet • In California, 50% of all mortgages are interest only right now • More risk for lending community and tax payers

  14. Environmental Variables • Climate Change • Where, When, How Much? • Environmental health of waters • Improved?? • Impacts on society • Aesthetics—quality of life • Environment and Recreation • Economic- Food Source

  15. Aging Infrastructure Including levees and dams • Repair? • Replace? • Remove? • Who Pays?

  16. Federal Budgets • Can the Federal Budget Support • Disaster Assistance? • Projects? • Flood Insurance Catastrophic Claim Years? • Natural Resource Restoration?

  17. Flood Damages in 2050 • Prior to Katrina Flood damages estimated at approximately $6 billion annually • By 2050 annual damages may exceed $10 billion annually- again ignoring Katrina—Cat event $200-400 billion …Unless we change the current process to address future changes and needs

  18. Katrina questions and lessons • Adequacy of 100-year standard in high risk areas? Critical facilities? • Layered protection (e.g. levees with flood insurance and/or floodplain management requirements)? • Should many areas plan for gradual retreat from high risk areas? Coast?

  19. Current Policy Disconnects • Who benefits---who pays • Development benefits go to locals who control land use, but can externalize… • Costs of damage to federal taxpayers • Disaster assistance—PA and IA • Tax deductions for casualty loss • Tax bailout of bankrupt programs

  20. Current Policy Disconnects • Public Safety v. 100 year flood • Public sees: • 100 year flood line as the “safe vs. not safe” line • Behind levee as safe v. not safe • Primary function and duty of local and states is public safety---Police and fire, but its also flood!

  21. Current Policy Disconnects • Risk communication • Risk is probability times consequences • Buy down the risk with a variety of tools-elevate, insurance, levee, but • Still have residual risk • Maps and insurance must convey the gradation of risk, not all or nothing

  22. Institutional Roles • Federal-state-local • In light of trends, can current heavy federal top down approaches work? • Who is best suited to do risk communication, technical assistance, mapping, data collection, mitigation planning and implementation, etc

  23. Controlling Risk in 2050 • Either by: • Control severity of flooding • Control value of what is placed at risk • Personal risk vs. societal risk • Who benefits---who pays? • Data—how will we get data to show the facts and make these decisions?

  24. Public Policy • “In effect, the national treasury bears a large part of the costs of those who prefer to live on floodplains, and does so without inquiring as to whether or not such plains afford any pronounced advantage for such occupance”

  25. Public Policy • “On the whole, present policy fosters an increasing dependence by individuals and local governments upon the federal government for leadership and financial support in dealing with flood problems” …has it changed?

  26. Public Policy • How do we change bad public policy? • Public outrage • Political will • Information and education are key

  27. Which adjustments effective? • Gilbert said: “All possible adjustments except those in land use and insurance tend to favor the preservation of existing land occupance” (in flood risk areas)

  28. Human Adjustments to Floods • Elevation • Flood Abatement (Watershed management) • Flood Protection (Structural flood control) • Emergency Measures • Structural Adjustments (adjustments to buildings and infrastructure) • Land Use • Public Relief • Insurance (Adapted from Gilbert F. White- 1942 Dissertation)

  29. Does Future Demand Additional Adjustment Factors? • If so, what might those factors be? • What strategies will get us prepared? • What is success? How measure it? • Those in this room you have the experience, knowledge and ability to develop recommendations that will guide the nation next 45 years

  30. These two days at Forum • Listen • Think • Contribute • Debate • Lets lay the foundation for that change in these two days

  31. Floodplain Management 2050 Larry Larson ASFPM www.floods.org