A Flood Insurance Rate Map (FIRM) displays the floodplains in a town or area. 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 or to know how to protect their property. The term is used mainly in the United States but similar maps exist in many other countries.
It is similar to a topographic map, but is designed mainly to show floodplains. Towns or Municipalities use it to plan zoning areas, for example, most places will not allow construction in a flood way.
In the United States the FIRM for each town is occasionally updated. At that time a preliminary FIRM will be published, and available for public viewing and comment. The Federal Emergency Management Agency (FEMA) sells the official FIRMs called Community Kits as well as an updating access service to the maps. There are also some companies that sell software to locate land parcels or real estate on digitized FIRMs.
FIRMs are used to set rates of insurance against risk of flood and whether buildings are insurable at all against flood.
- Definition of FIRM from Floodsmart.gov:
- Example of a town in the middle of updating FIRMs:
- Tropical Storm Allison Survivors may use this to lookup FIRMs:
- Free FIRMettes from FEMA: