Warren County, IA: flood risk, in FEMA's own numbers
On FEMA's National Risk Index, Warren County scores at the 35.9th percentile for flood hazard, rated "Relatively Low" — below the national norm for flood hazard. 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 2.9 times a year. County-wide, not parcel-specific: FEMA's real flood-zone map is queried live, never shipped as a download.
Who actually carries the flood insurance FEMA requires
6.6% of the homes FEMA requires to carry flood insurance in Warren County — those inside the mapped Special Flood Hazard Area — actually have a policy in force: 13 policies against 197 mandated structures, which means a meaningful share of legally-required coverage simply isn't there. Looking beyond the mandated zone, 0.1% of all residential structures in Warren County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
Where Warren County ranks
Among the 3144 US counties FEMA scores for flood hazard, Warren County ranks 2077 — 1 being the highest hazard nationally — and 932 by population among all 3144 counties covered here, where 1 is the largest. Warren County, Iowa covers 569.658 square miles and counts roughly 56,343 residents.
Your street may differ from Warren County's average
Across all of Warren County's 21,953 residential structures, 28 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
Where Warren 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.