Some SFHAs do not have BFEs shown on the flood maps. These SFHAs are shown as Zone A or Zone V and were determined by approximate methods.

Possible sources for obtaining a BFE in these areas may be the community’s planning, public works, engineering, environmental or transportation departments; the local district of the U.S. Army Corps of Engineers; or the State’s Environmental, Natural Resources, or Transportation Departments. Also, a registered professional engineer could conduct an engineering analysis to determine the BFE at the site.

For LOMA or LOMR-F applications with no BFE, FEMA may develop the BFE based on the best existing Digital Elevation Model (DEM) when more accurate data is not provided by the applicant. BFEs developed by FEMA using existing elevation data tend to be more conservative. Applications with detailed LiDAR or other elevation data and/or with Base Level Engineering studies will have better data, which should lead to more accurate BFE determinations.

Additional information regarding BFEs in these areas is available in the FEMA publication Managing Floodplain Development in Approximate Zone A Areas available at https://www.fema.gov/media-library/assets/documents/1911.