Ivins's Seismic Design Category, explained

Under the seismic model IBC and ASCE 7 use for new construction, Ivins 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. That puts Ivins in the 82th percentile nationally for seismic hazard - higher than 82% of the 4,875 US cities USGS was checked against here.

How Ivins compares

USGS's underlying values for Ivins: 0.21g peak ground acceleration, 0.476g at short period, 0.155g at 1 second. Within Utah alone, Ivins ranks 90 of 95 cities by seismic hazard - the 5th percentile in-state. Ivins has a population of about 11,108.

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.

Insuring against this, not just retrofitting

A Ivins 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 Ivins's figures come from

Ivins'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 Ivins.