St. George, UT: what USGS's seismic model says

Under the seismic model IBC and ASCE 7 use for new construction, St. George is Category D. High seismic hazard - this is the category most of coastal California, the Pacific Northwest, and other active fault regions fall into. Code mandates significant seismic detailing and restricts irregular structural configurations. This is the category the Brace + Bolt scope (cripple-wall bracing, foundation bolting) is built for. Rank it against the rest of the country and St. George sits at the 83th percentile for seismic hazard among 4,875 US cities.

Where St. George sits in Utah

USGS's underlying values for St. George: 0.225g peak ground acceleration, 0.512g at short period, 0.166g at 1 second. Within Utah alone, St. George ranks 88 of 95 cities by seismic hazard - the 7th percentile in-state. St. George has a population of about 106,288.

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 Utah 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 Utah.

What this means for insurance

A St. George 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 St. George's figures come from

St. George's Category D 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 D does and doesn't tell you about St. George.