Maquoketa's Seismic Design Category, explained

Maquoketa 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. Rank it against the rest of the country and Maquoketa sits at the 20th percentile for seismic hazard among 4,875 US cities.

How Maquoketa compares

USGS's underlying values for Maquoketa: 0.039g peak ground acceleration, 0.081g at short period, 0.058g at 1 second. Within Iowa alone, Maquoketa ranks 12 of 85 cities by seismic hazard - the 87th percentile in-state. Maquoketa has a population of about 6,064.

Retrofit economics for Maquoketa

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 Maquoketa 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 Maquoketa's figures come from

Maquoketa'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 Maquoketa.