Sedro-Woolley, WA: what USGS's seismic model says

Sedro-Woolley carries Seismic Design Category D under USGS's ASCE 7-16 model. 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 Sedro-Woolley sits at the 88th percentile for seismic hazard among 4,875 US cities.

How Sedro-Woolley compares

The raw figures: peak ground acceleration 0.425g, short-period spectral response 0.993g, 1-second spectral response 0.353g. Among 125 Washington cities in this dataset, Sedro-Woolley ranks 84 for seismic hazard, the 33th percentile within the state. About 13,215 people live in Sedro-Woolley, Washington.

Retrofit economics for Sedro-Woolley

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

Earthquake insurance for a Sedro-Woolley 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 Sedro-Woolley address.

More on how this number was built

The methodology guide covers exactly how USGS's public design-maps API produced Sedro-Woolley'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.