WASHINGTON -- Significant loss of life, destroyed property and businesses, and repairs to infrastructure could be avoided by replacing Federal Emergency Management Agency flood maps with ones that contain high-accuracy and high-resolution land surface elevation data, says a new report from the National Research Council. The benefits of more accurate flood maps will outweigh the costs, mainly because insurance premiums and building restrictions would better match the actual flood risks. Coastal region flood maps could also be improved by updating current models and using two-dimensional storm surge and wave models.
Flood maps are used by FEMA to set flood insurance rates, regulate floodplain development, and inform those who live in the "100-year" floodplain of potential hazards, and they require continuous maintenance and revision due to land development and natural changes to the landscape. FEMA's Map Modernization Program of 2003 to 2008 resulted in digital flood maps for 92 percent of the continental U.S. population, most of whom live in areas that had outdated maps or no maps at all. However, after a $1 billion investment, only 21 percent of the population have maps that meet all of FEMA's data quality standards.
For this reason, FEMA and the National Oceanic and Atmospheric Administration asked the Research Council to examine the factors that affect flood map accuracy; assess the costs and benefits of producing more accurate maps; and recommend ways to improve mapping, communication, and management of flood-related data. In response, the committee that wrote the report collected and analyzed information on selected streams in Florida and North Carolina and on the economic costs and benefits of creating new digital flood maps in North Carolina. Information from the North Carolina Floodplain Mapping Program, which has high-accuracy topographic data and maps for nearly the entire state, allowed the committee to compare new and trad
|Contact: Jennifer Walsh|
National Academy of Sciences