Levees: with Protection Comes Risk

FACT SHEET Living Behind Levees Information for Property Owners

LEVEES: PROTECTION WITH cornerstone of the nation’s strategy ACCREDITING A LEVEE DOES RISK for preparing communities for flood NOT GUARANTEE disasters. The NFIP was created to The United States has thousands of PROTECTION reduce flood damages by identifying miles of levees — usually earthen flood risks, encouraging sound embankments designed and community floodplain management constructed in accordance with sound When flood hazard maps identify the practices and providing flood engineering practices to contain, insurance. area behind a levee as being control or divert the flow of water so as to provide protection from protected against the one-percent- FEMA is updating the nation’s flood temporary flooding. Many levees annual-chance flood, the levee is said hazard data and maps, called Flood were first put in place by farmers to Map Modernization. Accurately to be accredited: it has met FEMA’s protect agricultural areas from identifying the flood risk behind frequent flooding. They date back as accreditation criteria. However, an levees is an important element of much as 150 years. Others have been Flood Map Modernization. Levees accredited levee does not guarantee designed to protect urban areas and are present in one out of every four were typically built to higher protection. counties being remapped. standards used by the U.S. Army Corps of Engineers. However, no FLOOD HAZARD MAPS levee provides full protection from FEMA flood maps identifying levees IDENTIFY THE RISKS flooding. will carry a warning that overtopping or Flood hazard maps (also known as failure of the levee, dike or other All levees are designed to provide a Flood Insurance Rate Maps, or specific level of protection and can be FIRMs) show the high-risk areas structure is possible, and that flood overtopped in larger flood events. where there is a one-percent chance insurance and adherence to Levees require regular maintenance of flooding in any given year. They to retain their level of protection. The also indicate the low- to moderate- evacuation procedures are strongly fact is, levees can and do decay over risk areas with a less than one-percent recommended. time, and maintenance can become a annual-chance of flooding. serious challenge. When levees do fail, or are overtopped, they fail Assessing flood risk for areas behind catastrophically — the flood damage levees is complex. Among the many may be more significant than if the factors the assessment must take into FOR MORE levee was not there. For these account are the actual elevations that INFORMATION, VISIT reasons, the millions of people a one-percent-annual-chance flood affected by levees need to understand will reach and the ability of the levee http://www.fema.gov/plan/prevent/fhm/lv_intro.shtm the flood risks they face and take to contain such floodwaters. FEMA steps to address them. has criteria for recognizing levees as protecting against the one-percent- FEMA’S ROLE annual-chance flood. However, FEMA does not examine structures or The Department of Homeland systems to determine how they will Security’s Federal Emergency perform in a flood event. The levee Management Agency (FEMA) owner is responsible for providing manages the National Flood documentation to show that the levee Insurance Program (NFIP), the meets the criteria.

OCTOBER 2006 PAGE 1 If a levee meets FEMA criteria, the flood hazard map will show the area behind the levee as a moderate risk zone. If it does not, the map will show the area as a high-risk area, or Special Flood Hazard Area (SFHA). The SFHA is the area flooded by the one-percent-annual-chance flood. The chart below shows how FEMA depicts these designations on flood maps and the requirements and options for flood insurance behind levees.

IF THE LEVEE… THE FEMA FLOOD MAP WILL AND THESE FLOOD SHOW THIS FLOOD RISK… INSURANCE REQUIREMENTS AND OPTIONS WILL APPLY…

Is not currently shown as High flood risk, with areas behind levees Flood insurance is required for providing protection from shown as being in a Special Flood Hazard structures with a federally backed the one-percent-annual- Area. mortgage. Insurance rates for buildings chance flood. (Area shown as A or AE zone on the constructed after the date of the initial (Non- Accredited) map) FIRM will be based on the height of the lowest floor as compared to the base flood elevation. Provides protection from Moderate flood risk, but flooding is still There is no mandatory insurance the one-percent-annual- possible. (Shown as B or shaded X zone purchase requirement in B or shaded X chance flood. on the map) zone. Lower-cost Preferred Risk (Accredited) Policies are available for most buildings in B or X zones. No longer meets the High flood risk, with areas behind levees Flood insurance is required for minimum standards to be shown as being in a Special Flood Hazard structures with a federally backed shown as providing protection Area. mortgage. Grandfathering saves from the one-percent-annual- (Shown as A, AE, AH, AO, V or VE zone) money. Buildings covered by flood chance flood. insurance prior to the effective date of (No Longer Accredited) new maps can be “grandfathered in” at more favorable insurance rates. Is temporarily shown as Moderate flood risk. Areas behind There is no mandatory insurance providing protection from levees are shown as being behind a purchase requirement in B or shaded X the one-percent-annual- Provisionally Accredited Levee, or PAL. zone, but flood insurance is strongly chance flood while additional (Area shown as a shaded X zone on the recommended. Lower-cost Preferred documentation is being map pending re-accreditation) Risk flood insurance is available for gathered. most buildings in B or X zones. (Provisionally Accredited)*

*For more detailed information about levees and flood risk zones, visit www.fema.gov/plan/prevent/fhm/lv_intro.shtm.

STEPS PROPERTY OWNERS CAN TAKE If you live behind a levee, there are things you can do to protect yourself and reduce the impact of flood events. First, be sure you understand your risk for flooding. Local officials can provide more information about the flood risk based on the location of the property. Second, obtain flood insurance — it is critically important to financially protect your investment. Finally, be aware of and always adhere to local evacuation procedures.

OCTOBER 2006 PAGE 2