Does Crystal, MN need an earthquake retrofit?

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Crystal in Seismic Design Category A: Lowest seismic design category. Building code requires no seismic-specific detailing here beyond ordinary construction practice. That puts Crystal in the 5th percentile nationally for seismic hazard - higher than 5% of the 4,875 US cities USGS was checked against here.

Where Crystal sits in Minnesota

The raw figures: peak ground acceleration 0.023g, short-period spectral response 0.048g, 1-second spectral response 0.028g. Among 155 Minnesota cities in this dataset, Crystal ranks 66 for seismic hazard, the 58th percentile within the state. About 22,082 people live in Crystal, Minnesota.

Bracing and bolting: the actual cost

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 Crystal address.

More on how this number was built

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