Does Westbrook, ME need an earthquake retrofit?

Under the seismic model IBC and ASCE 7 use for new construction, Westbrook is Category B. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. That puts Westbrook in the 64th percentile nationally for seismic hazard - higher than 64% of the 4,875 US cities USGS was checked against here.

Where Westbrook sits in Maine

USGS's underlying values for Westbrook: 0.17g peak ground acceleration, 0.287g at short period, 0.073g at 1 second. Within Maine alone, Westbrook ranks 14 of 20 cities by seismic hazard - the 32th percentile in-state. Westbrook has a population of about 21,386.

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 Maine 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 Maine.

What this means for insurance

A Westbrook 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 Westbrook's figures come from

Westbrook'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 Westbrook.