Algona's Seismic Design Category, explained

Algona 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. Nationally, Algona ranks above 7% of the 4,875 cities in this dataset for seismic hazard - the 7th percentile.

Where Algona sits in Iowa

USGS's underlying values for Algona: 0.025g peak ground acceleration, 0.054g at short period, 0.039g at 1 second. Within Iowa alone, Algona ranks 85 of 85 cities by seismic hazard - the 0th percentile in-state. Algona has a population of about 5,341.

Bracing and bolting: the actual cost

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 Algona 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 Algona's figures come from

Algona's Category A 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 A does and doesn't tell you about Algona.