Clear Lake, IA: what USGS's seismic model says

Clear Lake carries Seismic Design Category A under USGS's ASCE 7-16 model. Lowest seismic design category. Building code requires no seismic-specific detailing here beyond ordinary construction practice. Rank it against the rest of the country and Clear Lake sits at the 8th percentile for seismic hazard among 4,875 US cities.

Where Clear Lake sits in Iowa

The raw figures: peak ground acceleration 0.025g, short-period spectral response 0.052g, 1-second spectral response 0.041g. Among 85 Iowa cities in this dataset, Clear Lake ranks 84 for seismic hazard, the 1th percentile within the state. About 7,602 people live in Clear Lake, Iowa.

Retrofit economics for Clear Lake

Outside California, no state-level retrofit grant equivalent to Brace + Bolt could be found for Iowa. 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 Clear Lake address.

More on how this number was built

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