Cass County, IL flood risk explained
Flood hazard in Cass County sits at the 28.1th national percentile, 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 1.1 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 Cass County
18.6% of the homes FEMA requires to carry flood insurance in Cass County — those inside the mapped Special Flood Hazard Area — actually have a policy in force: 60 policies against 322 mandated structures, which means a meaningful share of legally-required coverage simply isn't there. Looking beyond the mandated zone, 2.5% of all residential structures in Cass County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
How Cass County compares nationally
Among the 3144 US counties FEMA scores for flood hazard, Cass County ranks 2310 — 1 being the highest hazard nationally — and 2240 by population among all 3144 counties covered here, where 1 is the largest. About 12,713 people live in Cass County, Illinois, spread over 375.754 square miles.
What to do next if you own or are buying in Cass County
126 of Cass County's 5,037 residential structures carry flood coverage of some kind, per FEMA's latest count — useful context, not a substitute for checking one parcel.
Where Cass 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.