Flood Risk Management and Nonstructural Flood Risk Adaptive Measures

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1 Flood Risk Management and Nonstructural Flood Risk Adaptive Measures Randall Behm, P.E., CFM USACE-Omaha District Chair, National Nonstructural Flood Proofing Committee US Army Corps of Engineers BUILDING STRONG The Ark at Estes Park, Colorado [elevation = 7522]

2 From a long retired USACE employee in 1985: All of the good flood control projects have already been built.

3 Another Week; Another Major Flood Event South Carolina Zion National Park, Utah High Tides, Florida and Alabama Sioux Falls, South Dakota Council Bluffs, Iowa Houston, Texas

4 Is this the new Normal for the United States ($38B to $54B annually from 2006 thru 2013 or $10B annually from 1985 thru 2013) Hurricane Sandy Colorado Flooding Hurricane Katrina Missouri River Flooding

5 Flood Risk Risk = f [(Probability of Flooding) x (Consequences)] (Probability of Flooding) is the frequency of flooding or how often does flooding occur in a particular location. Reduce the frequency of flooding and risk is reduced. (Consequences) are the potential damages and life loss associated with flooding. The structures (critical, residential, commercial, public, and industrial), land use (agricultural, urban, public), and infrastructure (highways, roads, rail, utilities) make up the potentially damageable assets. Reduce the consequences of flooding and risk is reduced. Note: If critical facilities become inoperative during a flood event, the area of impact extends beyond the area of flooding (fire and rescue, water and wastewater, electrical supply, communications, and cable TV).

6 Consequences Associated with Flooding Loss of Life Damage to Property Emergency Costs Business Losses Social Effects Health

7 Potential Climate Change Sea Level Rise Higher Flood Risk More Frequency of Flooding More Consequences

8 Critical Facilities and Flood Risk

9 Critical Facility Location Executive Order governs the location of critical facilities within the floodplain. If a facility such as a fire station, hospital, or EMS center becomes inoperable during a flood, the impact of the flood is then felt far beyond the area of inundation. In other words, the hardships caused by the flood are worsened on the population residing in and near the flooded area. Identify at-risk critical structures Determine their level of flood risk Communicate the risk to officials

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11 Tools which Support Reduced Flood Risk Land Use Zoning Building Codes Regulatory Permits Nonstructural Mitigation

12 What s Wrong With This Picture Why Is My Flood Insurance So Expensive? Uninformed Flood Response Desperation Flood Proofing

13 Then: 1944 Flood Control Act 1952 Council Bluffs Federal Levee Construction Now: Missouri River Levee Setback near State Hwy 2, Fremont County, IA Lower Flood Stages Lower Velocities More Resilient Reconnected Historic Floodplain Improved Environmental Benefits

14 EO13690; Federal Flood Risk Management Standards Why Implement? $260Billion in flood damages between Amends EO11988 to incorporate higher standards for Federal actions Three approaches for establishing future Base Flood Elevation: 1. Use best-available data, incorporating actionable climate science 2. Build 2-feet above the 100-year flood elevation or 3-feet above for critical facilities 3. Build to the 500-year flood elevation EO13690 does not change requirements for: o o Flood Insurance FEMA levee accreditation EO13690 anticipated to have minimal impacts on: o o 404 permit process PL84-99 RIP program

15 , and, and more, OH MY! We re off to see the Wizard the Wizard of FRAM

16 Nonstructural Flood Risk Management Definition Nonstructural flood risk management can be categorized as a set of physical or nonphysical measures utilized for mitigating loss of life as well as existing and future flood damages. The physical measures adapt to the natural characteristics of the floodplain without adversely affecting or changing those natural flood characteristics. These measures are generally compliant with the NFIP and cause no adverse affects to the floodplain, flood stages, velocities, or the environment. Because of their ability to adapt to flood risk, these measures may also be referred to as Flood Risk Adaptive Measures (FRAM) and can be incorporated into existing or new structures to mitigate for potential future flood damages and life loss.

17 Nonstructural Flood Risk Adaptive Measures The most common physical Flood Risk Adaptive Measures implemented for flood damage and life loss reduction are: Acquisition Relocation Elevation Dry Flood Proofing Wet Flood Proofing Basement Removal Nonphysical measures can be considered separately or as a combination of floodplain management and planning functions. Representative nonphysical measures are: Floodplain Mapping Land Use Flood Insurance Evacuation Plans Flood Warning Zoning Operational Changes Emergency Preparedness Plans

18 Future Flood Risk Management (Resiliency, Redundancy, Sustainability)

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20 * Caution Caution Caution * While nonstructural flood risk adaptive measures may result in lower property damages, there could be potential restrictions which the property owner needs to investigate prior to implementation: Local Ordinances State Regulations National Flood Insurance Program (NFIP) Note: Flood insurance is always recommended, even for structures which may have been retrofitted with nonstructural measures

21 Nonstructural Flood Risk Adaptive Measures Elevation on Extended Foundation Walls Elevation with Structural Slab on Segmented Piles

22 Elevation on Piers, Posts, Piles, or Columns

23 Nonstructural Flood Risk Adaptive Measures Relocation Acquisition

24 Dry Flood Proofing

25 Elevation on Fill

26 Elevation within a Historic Structure

27 Assessing the Situation Flood Characteristics Flood depth, Flood velocity, Flood duration, Rate of rise, Debris/Ice flows, Wave action, Floodway Encroachment Site Characteristics Location, Soil type, Topography, Parcel Size, Urban/Rural Building/Structure Characteristics Type of Construction, Foundation, Condition of the Building, Lower Levels (Basement), Historical Significance Other Considerations Building Occupancy, Building Codes, Zoning Ordinances and Local Restrictions, Other Agencies (Local / State / Federal), Aesthetics, Public Heath/Safety/Welfare

28 USACE National Nonstructural Flood Proofing Committee NFPC Members Randall Behm, Chair Kim Gavigan, Executive Secretary Steve O Leary Keven Lovetro Lea Adams Mary Weidel Bob Finch Brian Rast Technical Resources Publications Assessment Tools Barrier Testing Program Website Google: NFPC web site:

29 QUESTIONS? Randall L. Behm P.E., CFM (402)