Summary: GAO reviewed how the Federal Emergency Management Agency (FEMA) selects the method to map communities for entry into the National Flood Insurance Program and whether it is possible to expedite the conversion of the remaining communities without costly and time-consuming detailed mapping.
GAO found that FEMA uses three techniques that vary in duration and cost. Where a community has a large flood-prone area and has a potential for development, the standard method is to produce a rate map by doing a detailed study. This approach is costly and takes about 4 years. FEMA will occasionally take the existing data and produce a rate map similar to the one generated under the detailed study approach. Existing data study rate maps cost considerably less and take about 2 years to complete. Where no development has taken place in a community, FEMA can avoid detailed mapping by using a special process to convert the less detailed hazard map, that the community received to enter the emergency phase, into a rate map. The cost is relatively inexpensive and takes about 1 year. GAO found that FEMA has relied heavily on the detailed study approach to produce rate maps. GAO also found that the other mapping techniques, in particular the special conversion process, were implemented on an ad hoc basis and were not part of FEMA annual decisionmaking concerning which communities need rate maps.
