Flood Management Experiences in the United States

1
Flood Management Experiences in the United States

• January26, 2001
• Santiago Chile
• by
• Jerome Delli Priscoli Ph.D.

2
What I Will Cover

• 1. Context and History
• 2. Current Situation and Trends
• 3. Institutional Coordination
• 4. Strategies for Food Plain Management
• 5. Aspects of Policy, Planning and Analytics
• 6. Overcoming Barriers and New Directions

3
Context

• Federal System state, local
• resistance to Federal interference
• limited coordination on water
• Property rights
• individualism
• free market, private ownership
• Resistance to land use planning
• Flood management must integrate land use
• Lingering culture of primary structural responses
• Tradition of helping the victims
• reinforces discontinuity b/w assistance
  vs.mitigation, prevention

4
What is Flood Plain Management?

• continuous decision making process that aims to
  achieve the wise use of the Nations flood plain
  lands and waters
• Simultaneously present, near future,long term
• Balancing of relative costs - benefits and best
  mix structural and non structural tools
• Reducing risk through loss
• reduction strategies and tools
• Wise Use activities
• compatible with natural
• and human (life and property)

5
What is a Flood?

• Defining a Flood
• ..100 year flood, 1 annual chance flood or
  base flood, a flood of size that has a 1 chance
  of being equaled or exceeded in any given
  year.(Properties beyond 1 flood area still at
  risk)

6
Principles of Flood Plain Management in US

• Major Federal interest but basic responsibility
  with sate and local governments
• See flood plains in context of total community,
  regional and national planning and
  management
• Flood loss reduction seen in larger context of
  flood plain management - not an objective in
  itself
• Resource management often focus on resource
  which may not be entirely in flood plain.
• Benefits and costs interrelated impacts
• Evaluation of alternative strategies

7
Principles of Flood Plain Management in the US

• Major Federal interest but basic responsibility
  with sate and local governments
• See flood plains in context of total community,
  regional and national planning and management
• Flood loss reduction seen in larger context of
  flood plain management - not an objective in
  itself
• Resource management often focus on resource which
  may not be entirely in flood plain.
• Benefits and costs interrelated impacts
• evaluation of alternative strategies

8
The Situation in the US

• Over 150,000 square miles (94 million acres) or
  7 of country prone to floods
• Almost 10 million households and 390 billion in
  property are at risk today
• Rate of urban growth in flood plain twice the
  rest of country
• Average annual loss of life from floods stable
• Average annual flood losses rising
• Loss of natural flood storage continues
• But damages have increased in real dollars and
  disaster relief average 3 billion per year and
  uninsured losses are growing.

9
Situation (con.)

• Unprotected development in the 100 yr. plain and
  continued development just outside the 100 yr..
  Plain.
• Those deciding to live and do business in flood
  plain not paying proportionate costs of the
  decisions
• Grants and other post flood assistance reduce
  incentives to take preventative measures.
• 20,000 communities in flood plains, 90
  participate in NFIP but less then 20 of
  occupants buy insurance.

10
Trends

• Movements to coastal communities, adjacent to
  lakes and rivers
• Reduced ability to fund large capital measures
  those other measures such as codes, regulation
  increasing
• Rebalancing from structural to local planning,
  regulations, zoning, multipurpose management
• NFIP a primary tool of management and increased
  litigation over local government failure to
  endorse flood plain ordinances
• New awareness on natural functions of wetlands
  and internalization of EQ values
• Balance between public and private rights
  shifting to stronger pubic rights as pubic
  nuisances costs grow high Courts and legislatures
  evolving to reflect these concerns

11
Real Flood Damages 1903 - 1996 (Billions 95 s)
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Flood Plain Management US

• 18th and early 20th century Local problem and
  small scale structures
• Mid 20th century Federal role and large
  structures
• Later 20 the century back to more local and
  movement to mix small and large and non
  structural
• Can track approaches in language we have used
• 1800s flood prevention
• early 1900s flood control
• mid 1900s flood reduction
• latter 1900s flood plain management

14
History

• Much of History written around the Lower Miss -
  Delta
• By 1727 Nouvelle Orleans protected by 4 ft
  embankment
• 1543 DeSoto noted
• Indians raised mounds by hand and built high
  where they could
• From 1823 Federal role in water emerges -mostly
  navigation related with continual debate about
  flood control role with floods in mid 1800s to
  1917
• Debate in 1800s and early 1900s
• Ellet - mixed high levees, structure and outlets
• Humphreys Corps of engineers -levees only
• Humphreys wins out for 60 years until 1927 floods
• 1879 Miss river Commission
• Flood Control Act 1917 lower Miss - Sacramento
  river

15
History (con.)

• Flood Control Act of 1928 1927 floods greatest
  disaster in US history 700,000 homeless, 250
  million in losses
• previous 200 yrs. locals spent 300 million in
  lower Miss
• In single 1928 act Congress authorizes 325
  million - the greatest of budget for water
  projects ever in US!
• Ellet view of structures comes back
• Benefit cost ratio introduced
• DOA to work upstream and the Corps down but no
  coordination mechanism put in place
• Between 1936 -1952 spent 11 billion for flood
  control projects and storage single and mutli-
  purpose
• Idea was to build way out of the problem
• 1954 Watershed and Flood Prevention Act SCS of
  DOA
• 1940s to 1960s Broadening views, U of Chicago,

16
History (con.)

• 1953 first first major test by TVA land use and
  flood control measures
• 1950s, 60s move for water resources
  coordination - WRC and River Basin Org.s
• 1968 Flood Insurance Act
• 1976, 79, 86 and 94 National Program for Flood
  Plain Management revisions
• 1993 Upper Miss flood Galloway Report and 1994
  Revisions to President - 3 major recommendations
• Full consideration to all possible alternatives,
  evacuation, warning, proofing, natural and
  artificial storage
• full weight to social economic and environmental
  values in analysis
• more non structural to reduce vulnerability
  through use of flood plain management activities
  and programs

17
Institutional Coordination

• Private Sector
• Local Communities
• States
• Federal Agencies

Multiple actors owners, businesses, officials at
all levels, farmers developers, etc.
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Resource Protection
Red Cross
Disaster Assistance
Flood Management in U.S.
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Federal Emergency Management Agency US Army Corps
of Engineers Soil conservation Service National
Weather Service US Geological Survey Housing and
Urban Development Small Business
Administration Environmental Protection
Agency Department of Energy Forest
Service Economic Development Commission Department
of Transportation Pubic Health Service Bureau of
Reclamation US Fish and Wildlife Service Bureau
of Indian Affairs National Ocean Service National
Park Service

• Large Number of
• Actors Involved
• No WRC or formal
• coordinator
• Federal Agencies

21
Cost Sharing Today

• Evolves in Legis, of 36 38, 41, 74, 86, 96
• LERR D needs identified Value set and credited
  to non Fed contribution.
• Value of LERR D and 5 cash added if less then
  35 extra cash paid if more then 50 non Fed is
  reimbursed.
• Non Feds pay 50 of separable navigation and
  recreational costs assigned to project
• Non Feds provide all LERRDs and perform all
  related necessary relocations

22
Strategies and Tools for Flood Plain Management

• Modify Human Susceptibility to Flood Damage and
  Disruption
• Modify the Impact of Flooding on Individual and
  the Community
• Modify Flooding
• Preserve and Restore the Natural Resources
  Regulations
• Increasing Focus on Non Structural Measures
• reduce or avoid flood damages without significant
  altering the nature or extent of flooding.

23
Strategies and Tools for Flood Plain Management

• Modify Human Susceptibility to Flood Damage and
  Disruption
• Modify the Impact of Flooding on Individual and
  the Community
• Modify Flooding
• Preserve and Restore the Natural Resources
  Regulations
• Increasing Focus Non Structural Measures
• reduce or avoid flood damages without significant
  altering the nature or extent of flooding.

24
Modify Human Susceptibility to Flood Damage and
Disruption

• Flood Plain Regulations (Codes and zoning)
• Development and Redevelopment Policies
• Disaster Preparedness
• Disaster Assistance Flood Proofing, Flood
  Forecasting and Warning System and Emergency
  plans
• Problems linking evacuation
• and warning
• Preservation of
• Natural Resources

25
Flood Proofing Measures

• Elevation
• Relocation
• Barriers
• Dry Flood Proofing
• Wet Flood Proofing
• Buyout/Acquisition

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Preserve and Restore Natural Resources and
Functions of Flood Plains

• Floodplain, wetland, Coastal Barrier regulations
• Federal, State, Local, Regs, Zoning
• Development and Redevelopment Policies
• land acquisition and open space, relocation,
  restoration, habitat preservation, location of
  service utilities
• Information and Education
• Tax adjustments
• Administrative measures
• Beach Nourishment
• and Dune Building.

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Modify Flooding

• Dams and Reservoirs
• Dikes, Levees and Flood walls
• Channel Alterations
• High Flow Diversions
• Land Treatment
• On site Detention Shoreline protection
• Special Grasses

29
Modify the Impact of flooding

• Information and education
• Flood Insurance
• Tax Adjustments
• Flood Emergency Measures
• Post Flood Recovery

30
Key Rules for NFIP

• No residential living area below 1 flood level
• No non-residential development subject to damage
  by 1 flood
• No rebuilding below 1 if damage 50 or more of
  structures value
• Moving to actuarially based premiums or adjust
  according to use of mitigation
• Insurance industry participation in WYO program
  to bring expertise, spread coverage, improve
  service

• Measures must meet minimum FEMA and include
  zoning, subdivisions, building requirements,
  special purpose ordinances, outreach, education,
  others

31
NFIP (con.)

• Replacement costs for residential single family
  and residential
• condos insured at 80
• Some increased costs of compliance paid

32
Policy, Planning and Analytic Approaches for
Choosing Strategies and Tools
Uniform NFPM Prg. 76,79,86,94 Exec Orders,
Fed -State - Local Laws
Policy
Principles and Guidance for Water Resources
Planners 1983
Planning
Analytic Approaches BCA, Design
Standards Hydrologic Analysis
33
Principles and Guidance (P G) US Accounting
System for Public Water Investments

• National Economic Development (NED)
• beneficial and adverse effects on the national
  economy in monetary terms
• Environmental Quality (EQ)
• effects of plans on significant environmental
  resources and ecological, cultural and esthetic
  attributes
• Regional Economic Development (RED)
• distribution of regional economic activity from
  each plan in terms of regional income and
  employment
• Other Social Effects (OSE)
• effects on urban and community impacts, life,
  health, safety factors displacement, long term
  productivity energy requirements and energy
  conservation

34
Some Project Level Policies

• Must look at without Project Condition
• Flood Plain Management avoid its dev. and focus
  is on existing development
• Use risk based analytical framework expected
  performance (no minimum) not levels of protection
• can more small dams more residual
• Reflect residual damages
• Mitigation of induced flooding
• Address minimum flow Evaluate EQ mitigation
• No projects for single properties
• Include steps of the NFIP maps, etc.

35
Benefits Calculations

• Urban
• Inundation Reduction Benefits
• Intensification Benefits
• Location Benefits
• Damages Physical damages, Income loss, emergency
  costs
• Agriculture
• Damage Reduction
• Intensification
• Reduction in damage costs erosion,
  sedimentation, inadequate water supply
• Value of increased production of crops
• Economic efficiency of increasing production of
  crops

NOT CREATING NEW FLOODWAY DEVELOPMENT Benefits
cannot exceed the increased flood damage
potential in comparing existing activity to the
intensified/ changed activity
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Urban Flood Damage Benefit Evaluation
Delineate Affected Area
Forecast activities in affected area
Determine Flood plain
Estimate potential land use
Determine existing flood damages
Allocate land use
Estimate other flood related costs
Estimate future flood damages
Collect market value data
Compute benefits
37
Agricultural Benefit Evaluation Procedure
Identify land use - cropping pattern with and
without plan
For land where cropping pattern does not change
with plan
For land where cropping pattern changes with plan
Determine damage reduction benefit
Select method for intensification benefits
Use farm budget analysis
Use land value analysis
Determine Total Crop Benefit
38
Problems/Analytical-Planning Impediments

• BCA does not account for EQ, Social and
  Distribution effects
• Project by project impedes systematic
• Poorest with most serious problems not
  participating
• Lower value of poor in flood plain provide less
  economic justification

• Exclude reduction in disaster recovery cost as
  benefit
• Does not include avoided damages as additional
  benefits
• Communities w/o vitality resist NSF

39
Comparison Flood Depths vs. Location
Minn. vs. West Va.
40
Benefits of Non Structural Measures
Warning shifts stage-damage curve downward
Ad Hoc Method
Flood Warning PreparednessMethods for
Quantifying Benefits
41
Flood Warning Preparedness (Day Curve)
40
35
30
25
20
Reduction in Damages ()
15
10
5
0
0
6
12
18
24
30
36
42
48
Forecast Lead Time (in hours)
42
Policy Barriers to Non Structural

• Full accounting of EQ and non monetary social
  impacts on NSF is difficult
• Procedures used for BCR are based on certain
  assumptions that limit non-structural
• Emergency flood relief and recovery payments by
  Government (FEMA) create incentives against non
  structural
• FPM not being pursued in comprehensive fashion at
  all levels of government
• Those who live and work in flood zones not paying
  proportional cost of the decisions
• National policy on disaster response and
  assistance not aligned to management actually
  still creating incentives for locating in flood
  plain.

43
Analytical Barriers to NSFC

• Analytical Benefit Cost Analysis BCA
• Assess aggregate and blind to distribution
• Perfect market conditions assumed
• Dealing with non-monetized impacts
• based on economic return thus may encourage
  investments in high risk areas
• Policy Principles and Guidance P G and Policy
• NED maximization rule biased against EQ -Social
  Accounts
• Bias against broader non traditional benefits of
  NSF
• System not set up to recognize least cost
  alternative which may not be the best BCR
• Issue for Treasury is cash flow and policy does
  focus on minimizing tomorrow's losses

44
Overcoming Barriers Policy Directions

• Sustainability
• Nonstructural
• Structural
• Agricultural Policies
• Coastal
• Data and Technology
• Risk
• Repetitive Losses
• Property Rights.

45
Sustainability

• Move toward likely future conditions to make risk
  analysis more realistic

• Including disaster resiliency in community
  planning e.g.
• -FC measures flood resistant construction
  storm water management
• - Community zoning subdivision regulations

46
Increase Use of Non structural Measures

• Buyouts (1993 flooding)
• Elevating buildings
• Buffer zones and Levee set backs
• Keep vacated land in pubic ownership
• Seeking permanent authority for NSFC
• National riparian zone policy
• Natural storage capacity
• Building codes - International building code

47
Increase Use of Non structural Measures

• New construction 1 - 3 feet of freeboard above
  base flood elevation
• Use confidence levels (90 -95) for flood peak
  flows predictions
• No rise flood ways with no surface and velocity
  impacts
• Record waivers and disallow flood disaster
  assistance

48
Structural

• Must integrate structures and NSFC measures in
  planning
• Use water shed or basin wide approach
• Estimate useful life of existing FC structures
  and dam safety
• 200 failures in last 10yrs
• 9,200 categorized as high hazard
• 35 not inspected since 1990
• Rehab estimate over 1 billion
• New structures should be built to protect beyond
  the 1 to the 0.2 chance flood - avoid
  catastrophic floods
• Include failure zones of structures on flood
  hazard maps
• Increase incentives for dam safety program in
  states

49
Agricultural Policies

• Crop losses often exceed urban losses 1/2 all
  losses
• Examine prevalence of repeat areas of losses
• Need voluntary permanent Easements programs- deny
  subsidies-disaster payments if refuse
• Buffer zones - Conservation Reserve- 150 ft.
• Levees stop rebuilding where cost is greater
  then land value - reduce Federal subsidy of 80
  of costs
• Construct levees so no impact on height of 1
  flood

• Crop insurance programs can encourage
  plant in flood plains
• 1999 payments largest in US history at
  28 billion-they guarantee 50 of average
  yield 60-65 of all losses paid in 1998

50
Coastal

• Existing polices foster rather then discourage
  construction on coasts despite 1982 Barriers act
• NFIP not working for coastal areas, need
• integrate coastal areas into NFIP
• surcharge on areas subject to erosion
• setback requirements
• Shoreline erosion shift from jetties, sea walls
  to beach nourishment
• expensive and need better cost sharing
• consider setbacks and acquisition strategies
• increase pubic access to improved beaches

51
Data and Technology

• No one entity has responsibility for collecting
  and storing data about floods, defining floods,
  or damage!!
• of structures in flood hazard zone not known
  need data on repetitive loss structures
• FEMA Improving methods for estimating flood
  damage
• Stream gauge network is shrinking
• New modeling that include unsteady flow
  conditions, levee breaches, split flows and
  unstable land forms a debris flow being
  developed.
• Design manuals updated to include alternatives to
  structures and bioengineering.

52
Risk

• Need to improve risk communication
• 100 yr. becomes 1 or high risk flood
• 500 yr. becomes 0.2 or moderate risk flood
• Movement to risk based may mean more structures
  and away from design to a minimum standard and
  more structures will be built and increased
  exposure.
• Structures at 1 flood risk has 25 chance of
  being flooded during its 30 yr. Mortgagee a 1
  chance that same structure will have a fire - yet
  almost all have fire insurance and less then 25
  have flood insurance.
• Residual risk below structures Maps need to keep
  failure zones after structures in place

53
Risk - Perceptions

• Key to all is linking risk with behavior active
  choice/acceptance of risk versus passive being
  taken care of
• Engineers argued people felt more secure if see
  high levee or if see high earth dams versus
  stronger thin shell concrete
• Risk perception People living on St. Andraes
  fault cannot understand how people can live in
  the Delta exposed to risk Those in delta cannot
  understand those living on the fault line!

54
Property Rights

• Willing seller scenarios is basis
• key is partnership among levels of gov.and people
  (eg. Charles River in 1970s)
• Denial to rebuild as abridgment of rights
• eligibility criteria exists
• Restriction on right to flood fight as abridgment
• subject to state and community reg.s
• subject to liability of impacts on others
• National EQ programs as taking
• eg. Wetland permitting

55
Conclusions

• Flood Management is Complex
• We have much experience but still trying
• We have moved from fear to control to prevention
  to management and working with the floods
• Structures and non structures must work together.
• Changing behavior is critical.
• Movement to Active acceptance of risk and
  responsibility vs. passive paternalism
• The civic culture and civic infrastructure come
  together in flood management a learning ground
  for building Democratic civic culture.

56
Lessons for GWP

• Flood management important part of IWRM - optimal
  use but brings complexity
• links land to water upstream to downstream
• is a public good (eg.defense) thus offers
  additional revenue sources for IWRM projects
• help negotiating benefits vs. allocating flows
• Need to link post event reaction policy to
  anticipation, damage prevention and mitigation
  policies
• Hard to get benefits to poor if BC analysis is
  based on property values
• Critical issue is risk and culture changes
• communicating risk and reacting to warnings
• active choosing risk versus passive acceptance
  links to governance building civic culture and
  democracy
• From paternalism to informed consent

57
The Best Flood Proofing Measure Dont Build in
an Area that Floods.