FEMA

FEMA is the federal agency behind the flood facts property analysis relies on: it publishes the flood maps that define Special Flood Hazard Areas and base flood elevations, administers the National Flood Insurance Program those maps price, and maintains disaster and claims records that document where flood losses have actually occurred.

The agency's outputs deserve careful reading. Maps are regulatory instruments, revised over time and lagging physical reality in places; loss records reflect insured claims, not all flooding; and a lot's mapped status can change with an appeal or a restudy. Map, elevation, and loss history together give a rounded flood picture — each alone gives a partial one.