Galesburg's Seismic Design Category, explained

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Galesburg in Seismic Design Category B: 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 Galesburg sits at the 31th percentile for seismic hazard among 4,875 US cities.

How Galesburg compares

The raw figures: peak ground acceleration 0.052g, short-period spectral response 0.11g, 1-second spectral response 0.07g. Among 330 Illinois cities in this dataset, Galesburg ranks 298 for seismic hazard, the 10th percentile within the state. About 29,289 people live in Galesburg, Illinois.

What a retrofit costs in Galesburg

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.

What this means for insurance

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 Galesburg address.

More on how this number was built

The methodology guide covers exactly how USGS's public design-maps API produced Galesburg'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.