Houghton, MI: what USGS's seismic model says

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Houghton in Seismic Design Category A: Lowest seismic design category. Building code requires no seismic-specific detailing here beyond ordinary construction practice. Rank it against the rest of the country and Houghton sits at the 2th percentile for seismic hazard among 4,875 US cities.

Where Houghton sits in Michigan

USGS's underlying values for Houghton: 0.021g peak ground acceleration, 0.046g at short period, 0.017g at 1 second. Within Michigan alone, Houghton ranks 147 of 153 cities by seismic hazard - the 4th percentile in-state. Houghton has a population of about 8,543.

Bracing and bolting: the actual cost

A full earthquake retrofit typically runs $5,000-$10,000 nationally (around $7,000 typical), driven mainly by house size and foundation type, not by Michigan specifically. California's Earthquake Brace + Bolt grant, which covers a large share of this cost, is a California-only program and does not apply in Michigan.

Insuring against this, not just retrofitting

A Houghton homeowner cannot buy a standalone earthquake policy in most cases - it is added to an existing homeowners policy as an endorsement, so the place to start is a regular home-insurance quote.

Where Houghton's figures come from

Houghton's Category A and every number above trace to USGS's own ASCE 7-16 Design Maps service - see the methodology guide. See the category explainer for what Category A does and doesn't tell you about Houghton.