Dallas's Seismic Design Category, explained

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Dallas in Seismic Design Category D: High seismic hazard - this is the category most of coastal California, the Pacific Northwest, and other active fault regions fall into. Code mandates significant seismic detailing and restricts irregular structural configurations. This is the category the Brace + Bolt scope (cripple-wall bracing, foundation bolting) is built for. Nationally, Dallas ranks above 89% of the 4,875 cities in this dataset for seismic hazard - the 89th percentile.

Where Dallas sits in Oregon

USGS's underlying values for Dallas: 0.448g peak ground acceleration, 0.95g at short period, 0.484g at 1 second. Within Oregon alone, Dallas ranks 13 of 80 cities by seismic hazard - the 85th percentile in-state. Dallas has a population of about 17,911.

Retrofit economics for Dallas

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 Oregon 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 Oregon.

Insuring against this, not just retrofitting

A Dallas 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 Dallas's figures come from

Dallas's Category D 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 D does and doesn't tell you about Dallas.