Does Anaconda-Deer Lodge County, MT need an earthquake retrofit?

Under the seismic model IBC and ASCE 7 use for new construction, Anaconda-Deer Lodge County is 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. That puts Anaconda-Deer Lodge County in the 74th percentile nationally for seismic hazard - higher than 74% of the 4,875 US cities USGS was checked against here.

Anaconda-Deer Lodge County by the numbers

USGS's underlying values for Anaconda-Deer Lodge County: 0.143g peak ground acceleration, 0.324g at short period, 0.116g at 1 second. Within Montana alone, Anaconda-Deer Lodge County ranks 11 of 19 cities by seismic hazard - the 44th percentile in-state. Anaconda-Deer Lodge County has a population of about 9,811.

Retrofit economics for Anaconda-Deer Lodge County

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 Montana 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 Montana.

What this means for insurance

A Anaconda-Deer Lodge County 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 Anaconda-Deer Lodge County's figures come from

Anaconda-Deer Lodge County'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 Anaconda-Deer Lodge County.