Columbia, SC: what USGS's seismic model says

Columbia carries Seismic Design Category C under USGS's ASCE 7-16 model. Moderate seismic hazard. Code adds irregular-building restrictions and requires bracing of some nonstructural components (e.g. tall shelving, water heaters) in addition to structural detailing. Rank it against the rest of the country and Columbia sits at the 77th percentile for seismic hazard among 4,875 US cities.

How Columbia compares

USGS's underlying values for Columbia: 0.196g peak ground acceleration, 0.346g at short period, 0.115g at 1 second. Within South Carolina alone, Columbia ranks 25 of 66 cities by seismic hazard - the 63th percentile in-state. Columbia has a population of about 144,788.

Retrofit economics for Columbia

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 South 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 South Carolina.

What this means for insurance

A Columbia 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 Columbia's figures come from

Columbia's Category C 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 C does and doesn't tell you about Columbia.