A Flood Insurance Rate Map (FIRM) is a flood map created by the Federal Emergency Management Agency (FEMA) and is used by the National Flood Insurance Program (NFIP) for floodplain management, mitigation, and insurance purposes. A FIRM will generally show roads and map land marks, a community’s base flood elevations, flood zones, and floodplain boundaries.
FIRMs display areas that fall within the 100-year flood boundary. Areas that fall within the boundary are called special flood hazard areas (SFHAs) and they are further divided into insurance risk zones. The term 100-year flood indicates that the area has a one percent chance of flooding in any given year, not that a flood will occur every 100 years. Such maps are used in town planning, in the insurance industry, and by individuals who want to avoid moving into a home at risk of flooding. Property owners can use a FIRM to get reliable indications of what flood zone they are located. Town and municipalities use FIRMs to plan zoning areas, while most places will not allow construction in a flood way. Maps are, however, constantly being updated due to changes in geography, construction and mitigation activities, and meteorological events.