Is Lake County, IL in a flood zone?
FEMA's National Risk Index puts Lake County's flood hazard at the 97.2th percentile nationally — well above 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 2 times a year. This describes the county, not any one street — FEMA only publishes exact parcel zones through a live map service.
Mandatory flood insurance compliance in Lake County
Out of 4,579 homes FEMA counts inside Lake County's mapped flood zone, 1,114 carry the flood policy federal law requires there — 24.3% compliance, short of full coverage. Across all residential structures in Lake County, not just the ones FEMA mandates, 0.8% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
Lake County against the rest of the country
Lake County sits at rank 97 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 98 of 3144 by population (1 is biggest). Lake County, Illinois covers 443.68 square miles and counts roughly 718,604 residents.
Your street may differ from Lake County's average
FEMA counts 226,128 residential structures in Lake County overall, 1,857 of them carrying some form of NFIP coverage — but a lender or insurer cares about one parcel, not that county total.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Lake 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.