Carroll County, IA: flood risk, in FEMA's own numbers
On FEMA's National Risk Index, Carroll County scores at the 37.5th 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 1.8 times a year. County-wide, not parcel-specific: FEMA's real flood-zone map is queried live, never shipped as a download.
Carroll County's flood-insurance compliance gap
Homes with a federally backed mortgage inside Carroll 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, 28.6% of them do — 8 active policies against 28 structures FEMA counts in that zone, leaving a real compliance gap. Looking beyond the mandated zone, 0.2% of all residential structures in Carroll County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
How Carroll County compares nationally
Among the 3144 US counties FEMA scores for flood hazard, Carroll County ranks 2031 — 1 being the highest hazard nationally — and 1804 by population among all 3144 counties covered here, where 1 is the largest. Carroll County, Iowa covers 569.453 square miles and counts roughly 20,407 residents.
Checking a specific address in Carroll County
Across all of Carroll County's 8,506 residential structures, 14 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
Where Carroll 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.