Is Clayton County, IA in a flood zone?
FEMA's National Risk Index puts Clayton County's flood hazard at the 58th percentile nationally — below the national norm for flood hazard — driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 4.4 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 Clayton County
13.2% of the homes FEMA requires to carry flood insurance in Clayton County — those inside the mapped Special Flood Hazard Area — actually have a policy in force: 79 policies against 598 mandated structures, which means a meaningful share of legally-required coverage simply isn't there. Across all residential structures in Clayton County, not just the ones FEMA mandates, 0.9% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Where Clayton County ranks
Clayton County sits at rank 1383 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 1983 of 3144 by population (1 is biggest). About 16,931 people live in Clayton County, Iowa, spread over 778.464 square miles.
What to do next if you own or are buying in Clayton County
85 of Clayton County's 9,008 residential structures carry flood coverage of some kind, per FEMA's latest count — useful context, not a substitute for checking one parcel.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Clayton 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.