Reading a Floodplain Map

Reading a Floodplain Map

August 7, 2018

Floodplain mapping terminology is used frequently and just as often misunderstood. For instance, a 100-year flood has a 26% chance of occurring during a 30-year period (the length of most home mortgages).

In this MooreWISE brief, Lizzy Bache answers the question, "What does a floodplain map tell you?"

Since the 1970s, FEMA has been creating a database of floodplain maps to help communities mitigate their flood risk through participation in the National Flood Insurance Program (NFIP). These floodplain maps, referred to as Flood Insurance Rate Maps (FIRMs), provide an abundance of information to the user, such as: map land marks, highway information, base flood elevations, flood zones, and floodplain boundaries.