Does Powell, WY need an earthquake retrofit?

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Powell in Seismic Design 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, Powell ranks above 75% of the 4,875 cities in this dataset for seismic hazard - the 75th percentile.

Powell by the numbers

The raw figures: peak ground acceleration 0.157g, short-period spectral response 0.282g, 1-second spectral response 0.087g. Among 16 Wyoming cities in this dataset, Powell ranks 10 for seismic hazard, the 40th percentile within the state. About 6,551 people live in Powell, Wyoming.

Bracing and bolting: the actual cost

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

Earthquake insurance for a Powell 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 Powell address.

More on how this number was built

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