Chillicothe, IL: what USGS's seismic model says

Chillicothe 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 Chillicothe sits at the 39th percentile for seismic hazard among 4,875 US cities.

Chillicothe by the numbers

The raw figures: peak ground acceleration 0.063g, short-period spectral response 0.131g, 1-second spectral response 0.074g. Among 330 Illinois cities in this dataset, Chillicothe ranks 192 for seismic hazard, the 42th percentile within the state. About 6,052 people live in Chillicothe, Illinois.

Bracing and bolting: the actual cost

Outside California, no state-level retrofit grant equivalent to Brace + Bolt could be found for Illinois. A typical retrofit still runs $5,000-$10,000 nationally, about $7,000 for a common single-family job.

Insuring against this, not just retrofitting

Outside California, earthquake coverage is typically sold as an endorsement added to a standard homeowners policy, not a separate product - worth asking about directly when getting a home-insurance quote for a Chillicothe address.

More on how this number was built

The methodology guide covers exactly how USGS's public design-maps API produced Chillicothe's numbers. The guide to what a Seismic Design Category actually means covers why a category is never a substitute for an engineer's assessment of one specific house.