Is Decatur County, IA in a flood zone?
FEMA's National Risk Index puts Decatur County's flood hazard at the 15.8th percentile nationally — among the lowest flood hazard in the country — driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 1.8 times a year. County-wide, not parcel-specific: FEMA's real flood-zone map is queried live, never shipped as a download.
Mandatory flood insurance compliance in Decatur County
Out of 12 homes FEMA counts inside Decatur County's mapped flood zone, 0 carry the flood policy federal law requires there — 0% compliance, short of full coverage. Across all residential structures in Decatur County, not just the ones FEMA mandates, 0% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Decatur County against the rest of the country
Decatur County sits at rank 2677 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 2600 of 3144 by population (1 is biggest). Decatur County, Iowa is home to about 7,656 people across 531.883 square miles of land.
What to do next if you own or are buying in Decatur County
Across all of Decatur County's 3,553 residential structures, 0 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Decatur County's numbers. The guide to what the Special Flood Hazard Area actually means explains why the mandatory-insurance rule exists and who it applies to.