Whiteside County, IL: flood risk, in FEMA's own numbers
On FEMA's National Risk Index, Whiteside County scores at the 70.1th 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 1.9 times a year. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Who actually carries the flood insurance FEMA requires
24.2% of the homes FEMA requires to carry flood insurance in Whiteside County — those inside the mapped Special Flood Hazard Area — actually have a policy in force: 133 policies against 549 mandated structures, which means a meaningful share of legally-required coverage simply isn't there. Looking beyond the mandated zone, 0.7% of all residential structures in Whiteside County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
How Whiteside County compares nationally
Among the 3144 US counties FEMA scores for flood hazard, Whiteside County ranks 982 — 1 being the highest hazard nationally — and 950 by population among all 3144 counties covered here, where 1 is the largest. Whiteside County, Illinois is home to about 54,657 people across 684.099 square miles of land.
Checking a specific address in Whiteside County
Across all of Whiteside County's 21,899 residential structures, 158 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
Where Whiteside 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.