A flood insurance rate map, or FIRM, is the official map that outlines a community's floodplain boundaries, flood elevations and flood zones. FIRMs, created by the National Flood Insurance Program, are used by property owners, renters, lenders and insurance companies to determine a property's flood risk.
FIRMs can be obtained on the Federal Emergency Management Agency Flood Map Service Center website or the National Flood Insurance Program's website. Since FIRMs are constantly updated due to geographical, weather and construction changes, the most accurate sources for rate and flood zone information are flood insurance providers and local government offices. Flood insurance is mandatory when a property sits within a high-risk flood zone.