Does Sault Ste. Marie, MI need an earthquake retrofit?

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

Where Sault Ste. Marie sits in Michigan

The raw figures: peak ground acceleration 0.024g, short-period spectral response 0.051g, 1-second spectral response 0.023g. Among 153 Michigan cities in this dataset, Sault Ste. Marie ranks 143 for seismic hazard, the 7th percentile within the state. About 13,288 people live in Sault Ste. Marie, Michigan.

Retrofit economics for Sault Ste. Marie

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

Earthquake insurance for a Sault Ste. Marie home

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 Sault Ste. Marie address.

More on how this number was built

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