Des Moines, WA: what USGS's seismic model says

Under the seismic model IBC and ASCE 7 use for new construction, Des Moines 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 Des Moines sits at the 93th percentile for seismic hazard among 4,875 US cities.

Where Des Moines sits in Washington

USGS's underlying values for Des Moines: 0.592g peak ground acceleration, 1.397g at short period, 0.478g at 1 second. Within Washington alone, Des Moines ranks 21 of 125 cities by seismic hazard - the 84th percentile in-state. Des Moines has a population of about 33,207.

Retrofit economics for Des Moines

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 Washington 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 Washington.

Earthquake insurance for a Des Moines home

A Des Moines 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 Des Moines's figures come from

Des Moines'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 Des Moines.