Does Davenport, IA need an earthquake retrofit?

Davenport carries Seismic Design Category B under USGS's ASCE 7-16 model. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. That puts Davenport in the 25th percentile nationally for seismic hazard - higher than 25% of the 4,875 US cities USGS was checked against here.

Davenport by the numbers

The raw figures: peak ground acceleration 0.044g, short-period spectral response 0.093g, 1-second spectral response 0.064g. Among 85 Iowa cities in this dataset, Davenport ranks 6 for seismic hazard, the 94th percentile within the state. About 100,938 people live in Davenport, Iowa.

Bracing and bolting: the actual cost

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 Davenport address.

More on how this number was built

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