Does Ponca City, OK need an earthquake retrofit?

Under the seismic model IBC and ASCE 7 use for new construction, Ponca City is Category B. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. That puts Ponca City in the 43th percentile nationally for seismic hazard - higher than 43% of the 4,875 US cities USGS was checked against here.

Where Ponca City sits in Oklahoma

The raw figures: peak ground acceleration 0.067g, short-period spectral response 0.134g, 1-second spectral response 0.064g. Among 75 Oklahoma cities in this dataset, Ponca City ranks 53 for seismic hazard, the 30th percentile within the state. About 24,234 people live in Ponca City, Oklahoma.

Retrofit economics for Ponca City

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

Insuring against this, not just retrofitting

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 Ponca City address.

More on how this number was built

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