Post on 27-Dec-2015
NAVIGATING THE TURN: FLOOD RISK ASSOCIATED WITH
LEVEES
Sam Riley Medlock, J.D., CFM
Association of State Floodplain Managers
May 2011
Briefing Overview
Current State & How We Got Here
Visions of Success
How We Get There
Conclusion:Preparing the Nation for Future Floods
Briefing Overview
Current State & How We Got Here
Visions of Success
How We Get There
Conclusion:Preparing the Nation for Future Floods
Floods, Disasters & Risk
"Floods are acts of God, but flood losses are largely acts of man.”
- Gilbert F. White, Human Adjustments to Floods, 1945
Floodplain Managers are Flood Risk Managers
Risk = Probability x Consequences
5
Floods, Levees & Human Settlement
• Early Anglo-American settlements followed water courses
• Levees were viewed as a key defense
6
Major flood disasters 1849 – 1936 spurred national leadership in Congress
Floods, Levees & Human Settlement
Floods, Levees & the 100-Year Problem
1981, FEMA FIA• “[T]he 100-year standard [is] encouraging
construction of levees to the 100-year design level for the sole purpose of removing an area from the special flood hazard designation.”
• Crediting a levee system with protection against the 100-year flood could violate the spirit of the National Flood Insurance Act.
Key Recommendations of Reports: 1970s - 2010
• “100-year” standard inadequate for flood damage reduction structures, especially for urbanized areas
• Structural measures – as a single risk reduction measure - are incomplete and require consideration of land use policies
• Greater emphasis & support needed on nonstructural approaches
Policies Contribute to Risk
•NFIP & the 100-Year Standard•Emphasis on structural approaches•Disaster relief environment•Lack of attention to climate adaptation
Federal Policies
• Control land use for short-term benefits
• Perceive flooding to be a federal problem
• Externalize the costs & consequences
States & Communities
• Unaware of – or unwilling to accept - residual risk
• Misplaced concern about having to obtain flood insurancePublic
Nation’s Levee Problem
• Scope of Nation’s Vulnerability = Unknown– How many miles of levees?– Condition of existing levees?
• Increasing Development Behind Levees• New Levees Being Sought to Protect
Undeveloped Land
National Levee Inventory
0
25000
50000
75000
100000
Miles of Levees
Levees proliferate the American Landscape• Relied upon to Protect People, Property, and other Infrastructure• Estimated that tens of millions of people live and work in leveed areas
No National Standards or Approaches• Designed for one purpose now serving another• Systems based approaches were most often not used, but are needed
Risk: A Dynamic that We Can Keep Up With?• Average age of 50 years, Climate Change, Infrastructure Degradation, & Increasing
Population Growth
USACE Program Levees Addl FederalNon-Federal
Briefing Overview
Current State & How We Got Here
Visions of Success
How We Get There
Conclusion:Preparing the Nation for Future Floods
14
• Equity– Geographic– Intergenerational
• Sustainability– Environmental– Economic
• Resiliency– Existing hazards– Foreseeable
Principles of Success
Visions of Success
• National Flood Risk Management Program– Levee Safety
• Complete inventory of all levees in the Nation• Robust Levee Programs in All States• Incentives / Disincentives Drive Smart Action• Public Understanding of Residual Risk• Improved Levels of Protection & Strength• Nonstructural Measures Fully Integrated• National Standards and Codes• Clear Roles in Risk Reduction
Briefing Overview
Current State & How We Got Here
Visions of Success
How We Get There
Conclusion:Preparing the Nation for Future Floods
Future Remedies: Reduce Risk
• Hazard– Increasing design standards– Improving structural performance
• Lower the Consequence– Gradually relocate families and businesses
from leveed areas (restore floodplain function)– Steer new development from flood-prone
areas– Adjustments for SLR and
changing precip patterns
Navigating the Turn
• Existing Investment At Risk– Strategic Investment– Nonstructural– O&M
• Future Development– Land Use/Zoning– Siting – Design– Resiliency
18
National Committee on Levee Safety
ASFPM supports much of the Report:• Expand & Complete National
Levee Inventory including nonfederal levees
• Robust safety programs in every state
• Require flood insurance behind all levees
• Levee Hazard Classification System
• National standards & codes• Public Engagement & Risk
Communication
Levee Safety Policy– Full Integration with
Flood Risk Management
– Land Use Requirements
– Integrate Climate Adaptation
– Alternatives to structural approaches
NCLS Review Team Comments
Immediate Action to Curtail Federal activities and investments that contribute to risk
Nonfederal Action
• Challenges– Funding– Prioritization– Competition among all classes of aging
infrastructure• States & Local Opportunities
– No Adverse Impact– Adopt standards,
enforce equitably– Identify and reduce legal liability
• Manage resources and plan on a watershed basis;• Integrate plans and activities to reflect all hazards,
to identify actions with multiple benefit;• Permanently restore and preserve flood-prone
areas as open space, through land acquisition; and• Anticipate future development and site critical
facilities out of harm’s way.
States, Regions & Local Actions
Briefing Overview
Current State & How We Got Here
Visions of Success
How We Get There
Conclusion:Preparing the Nation for Future Floods
Community Resiliency
• Extreme events are on the rise• Extreme events are disruptive• Resilience is built at the community level• Resilience requires participation of all
sectors
• Common interests & goals