Decatur, TX: what USGS's seismic model says
Decatur 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. That puts Decatur in the 35th percentile nationally for seismic hazard - higher than 35% of the 4,875 US cities USGS was checked against here.
Decatur by the numbers
USGS's underlying values for Decatur: 0.058g peak ground acceleration, 0.118g at short period, 0.055g at 1 second. Within Texas alone, Decatur ranks 46 of 384 cities by seismic hazard - the 88th percentile in-state. Decatur has a population of about 8,266.
Retrofit economics for Decatur
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.
What this means for insurance
A Decatur 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 Decatur's figures come from
Decatur'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 Decatur.