Does Aiken, SC need an earthquake retrofit?
USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Aiken in Seismic Design Category C: 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. Nationally, Aiken ranks above 75% of the 4,875 cities in this dataset for seismic hazard - the 75th percentile.
Aiken by the numbers
USGS's underlying values for Aiken: 0.157g peak ground acceleration, 0.288g at short period, 0.103g at 1 second. Within South Carolina alone, Aiken ranks 51 of 66 cities by seismic hazard - the 23th percentile in-state. Aiken has a population of about 32,694.
Retrofit economics for Aiken
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.
Insuring against this, not just retrofitting
A Aiken 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 Aiken's figures come from
Aiken'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 Aiken.