Idaho vs Montana Earthquake Risk

Idaho and Montana share the same risk score of 6/10 (Moderate-High). Both states face similar levels of seismic hazard, though the specific fault systems and earthquake characteristics differ.

Idaho averages approximately 100 earthquakes per year, while Montana averages about 150 per year. Montana experiences roughly 50 more earthquakes annually.

Idaho is associated with Lost River, Lemhi, Beaverhead faults. Montana is associated with Intermountain Seismic Belt, Lewis & Clark zone. These fault systems determine the type and frequency of seismic activity each state experiences.

In Idaho, approximately 45% of the population lives in areas at risk from earthquakes, compared to 50% in Montana. Montana has a larger percentage of residents exposed to seismic hazard.

Idaho's most notable earthquake: 1983 Borah Peak (M6.9). Montana's most notable earthquake: 1959 Hebgen Lake (M7.3). These historical events illustrate the seismic potential of each state.