While improvements to inland flood maps can focus on harnessing available technology, coastal flood maps could be improved by employing better models that enhance understanding of the coastal flooding process. The committee recommended improving the accuracy of base flood elevations by replacing FEMA's one-dimensional model for calculating wave heights, which was introduced in the 1970s, with a two-dimensional wave model. Further enhancements could come by coupling this with a two-dimensional surge model and including models that account for erosion processes, effects on structures, and variations in elevation.
FEMA's transition to digital flood mapping also provides opportunities for better informing the public of flood hazards and risks through maps and Web-based products, the committee noted. To adequately convey risk, the maps and products must show where the flood hazard areas are located and the likely consequences of flooding, such as damage to houses or coastal erosion. Additionally, floodplain residents should know how their land elevation level compares with various possible flood heights, which will offer a finer discrimination of potential risk. Currently, maps that show only floodplain boundaries imply that every building in a designated flood zone may flood and every building outside the zone is safe.
The National Academy of Sciences, National Academy of Engineering, Institute of Medicine, and National Research Council make up the National Academies. They are independent, nonprofit institutions that provide science, technology, and health policy advice under an 1863 congressional charter. Committee members, who serve pro bono as volunteers, are chosen by the Academies for each study based on their expertise and experience and must satisfy the Academies' conflict-of-interest standards. The resulting consensus reports undergo external peer review before completion. For more information, visit
|Contact: Jennifer Walsh|
National Academy of Sciences