Does Bristol, WI need an earthquake retrofit?

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Bristol 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 Bristol sits at the 26th percentile for seismic hazard among 4,875 US cities.

How Bristol compares

The raw figures: peak ground acceleration 0.046g, short-period spectral response 0.093g, 1-second spectral response 0.054g. Among 157 Wisconsin cities in this dataset, Bristol ranks 6 for seismic hazard, the 97th percentile within the state. About 5,239 people live in Bristol, Wisconsin.

Retrofit economics for Bristol

Outside California, no state-level retrofit grant equivalent to Brace + Bolt could be found for Wisconsin. 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 Bristol address.

More on how this number was built

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