Does Waverly, IA need an earthquake retrofit?

Under the seismic model IBC and ASCE 7 use for new construction, Waverly is Category B. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. That puts Waverly in the 16th percentile nationally for seismic hazard - higher than 16% of the 4,875 US cities USGS was checked against here.

Where Waverly sits in Iowa

USGS's underlying values for Waverly: 0.027g peak ground acceleration, 0.055g at short period, 0.045g at 1 second. Within Iowa alone, Waverly ranks 67 of 85 cities by seismic hazard - the 21th percentile in-state. Waverly has a population of about 10,576.

What a retrofit costs in Waverly

A full earthquake retrofit typically runs $5,000-$10,000 nationally (around $7,000 typical), driven mainly by house size and foundation type, not by Iowa specifically. California's Earthquake Brace + Bolt grant, which covers a large share of this cost, is a California-only program and does not apply in Iowa.

Insuring against this, not just retrofitting

A Waverly homeowner cannot buy a standalone earthquake policy in most cases - it is added to an existing homeowners policy as an endorsement, so the place to start is a regular home-insurance quote.

Where Waverly's figures come from

Waverly's Category B and every number above trace to USGS's own ASCE 7-16 Design Maps service - see the methodology guide. See the category explainer for what Category B does and doesn't tell you about Waverly.