Greenville, IL: what USGS's seismic model says

Greenville carries Seismic Design Category D under USGS's ASCE 7-16 model. 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. That puts Greenville in the 84th percentile nationally for seismic hazard - higher than 84% of the 4,875 US cities USGS was checked against here.

Greenville by the numbers

USGS's underlying values for Greenville: 0.259g peak ground acceleration, 0.446g at short period, 0.155g at 1 second. Within Illinois alone, Greenville ranks 30 of 330 cities by seismic hazard - the 91th percentile in-state. Greenville has a population of about 7,126.

Bracing and bolting: the actual cost

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 Illinois 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 Illinois.

Earthquake insurance for a Greenville home

A Greenville 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 Greenville's figures come from

Greenville'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 Greenville.