Henderson County, IL: flood risk, in FEMA's own numbers
On FEMA's National Risk Index, Henderson County scores at the 24.7th 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 1.9 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 Henderson County
Out of 183 homes FEMA counts inside Henderson County's mapped flood zone, 60 carry the flood policy federal law requires there — 32.8% compliance, short of full coverage. Looking beyond the mandated zone, 2.1% of all residential structures in Henderson County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
How Henderson County compares nationally
Among the 3144 US counties FEMA scores for flood hazard, Henderson County ranks 2412 — 1 being the highest hazard nationally — and 2726 by population among all 3144 counties covered here, where 1 is the largest. About 6,048 people live in Henderson County, Illinois, spread over 378.793 square miles.
Your street may differ from Henderson County's average
FEMA counts 3,543 residential structures in Henderson County overall, 75 of them carrying some form of NFIP coverage — but a lender or insurer cares about one parcel, not that county total.
Where Henderson 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.