Clarkston, WA: what USGS's seismic model says

Under the seismic model IBC and ASCE 7 use for new construction, Clarkston is Category C. Moderate seismic hazard. Code adds irregular-building restrictions and requires bracing of some nonstructural components (e.g. tall shelving, water heaters) in addition to structural detailing. Nationally, Clarkston ranks above 73% of the 4,875 cities in this dataset for seismic hazard - the 73th percentile.

How Clarkston compares

The raw figures: peak ground acceleration 0.133g, short-period spectral response 0.298g, 1-second spectral response 0.107g. Among 125 Washington cities in this dataset, Clarkston ranks 124 for seismic hazard, the 1th percentile within the state. About 7,138 people live in Clarkston, Washington.

Bracing and bolting: the actual cost

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.

What this means for insurance

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 Clarkston address.

More on how this number was built

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