St. Francis's Seismic Design Category, explained

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places St. Francis in Seismic Design Category A: Lowest seismic design category. Building code requires no seismic-specific detailing here beyond ordinary construction practice. Nationally, St. Francis ranks above 3% of the 4,875 cities in this dataset for seismic hazard - the 3th percentile.

How St. Francis compares

The raw figures: peak ground acceleration 0.022g, short-period spectral response 0.048g, 1-second spectral response 0.023g. Among 155 Minnesota cities in this dataset, St. Francis ranks 132 for seismic hazard, the 15th percentile within the state. About 8,523 people live in St. Francis, Minnesota.

What a retrofit costs in St. Francis

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

More on how this number was built

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