Does Alton, TX need an earthquake retrofit?

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Alton in Seismic Design Category A: Lowest seismic design category. Building code requires no seismic-specific detailing here beyond ordinary construction practice. That puts Alton in the 2th percentile nationally for seismic hazard - higher than 2% of the 4,875 US cities USGS was checked against here.

How Alton compares

USGS's underlying values for Alton: 0.02g peak ground acceleration, 0.043g at short period, 0.013g at 1 second. Within Texas alone, Alton ranks 361 of 384 cities by seismic hazard - the 6th percentile in-state. Alton has a population of about 22,907.

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 Texas 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 Texas.

Earthquake insurance for a Alton home

A Alton 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 Alton's figures come from

Alton'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 Alton.