Poweshiek County, IA: flood risk, in FEMA's own numbers
On FEMA's National Risk Index, Poweshiek County scores at the 20.3th percentile for flood hazard, rated "Very Low" — among the lowest flood hazard in the country. The hazard here is driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about once every 1 years. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Who actually carries the flood insurance FEMA requires
Homes with a federally backed mortgage inside Poweshiek County's mapped high-risk flood zone (the Special Flood Hazard Area, or SFHA) are legally required to carry an NFIP flood policy. In practice, 25% of them do — 4 active policies against 16 structures FEMA counts in that zone, leaving a real compliance gap. Looking beyond the mandated zone, 0.1% of all residential structures in Poweshiek County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
Where Poweshiek County ranks
Among the 3144 US counties FEMA scores for flood hazard, Poweshiek County ranks 2546 — 1 being the highest hazard nationally — and 1909 by population among all 3144 counties covered here, where 1 is the largest. About 18,454 people live in Poweshiek County, Iowa, spread over 584.932 square miles.
Checking a specific address in Poweshiek County
Across all of Poweshiek County's 8,214 residential structures, 7 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
Where Poweshiek County's figures come from
Every figure on this page traces to a named FEMA dataset, documented in the methodology guide. If you're unsure why any of this insurance requirement exists at all, the SFHA explainer covers it from first principles.