Freeport, IL: what USGS's seismic model says

Freeport carries Seismic Design Category B under USGS's ASCE 7-16 model. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. Rank it against the rest of the country and Freeport sits at the 29th percentile for seismic hazard among 4,875 US cities.

Where Freeport sits in Illinois

USGS's underlying values for Freeport: 0.048g peak ground acceleration, 0.097g at short period, 0.057g at 1 second. Within Illinois alone, Freeport ranks 321 of 330 cities by seismic hazard - the 3th percentile in-state. Freeport has a population of about 23,140.

Retrofit economics for Freeport

A full earthquake retrofit typically runs $5,000-$10,000 nationally (around $7,000 typical), driven mainly by house size and foundation type, not by Illinois specifically. California's Earthquake Brace + Bolt grant, which covers a large share of this cost, is a California-only program and does not apply in Illinois.

What this means for insurance

A Freeport homeowner cannot buy a standalone earthquake policy in most cases - it is added to an existing homeowners policy as an endorsement, so the place to start is a regular home-insurance quote.

Where Freeport's figures come from

Freeport's Category B and every number above trace to USGS's own ASCE 7-16 Design Maps service - see the methodology guide. See the category explainer for what Category B does and doesn't tell you about Freeport.