Trinity, NC: what USGS's seismic model says

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Trinity in Seismic Design Category B: 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 Trinity sits at the 47th percentile for seismic hazard among 4,875 US cities.

Trinity by the numbers

USGS's underlying values for Trinity: 0.073g peak ground acceleration, 0.149g at short period, 0.069g at 1 second. Within North Carolina alone, Trinity ranks 86 of 147 cities by seismic hazard - the 42th percentile in-state. Trinity has a population of about 7,190.

Retrofit economics for Trinity

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 North Carolina 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 North Carolina.

Insuring against this, not just retrofitting

A Trinity 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 Trinity's figures come from

Trinity'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 Trinity.