Idaho vs Washington Earthquake Risk

Washington has a higher earthquake risk with a score of 8/10 (High) compared to Idaho at 6/10 (Moderate-High). This means Washington faces more frequent and potentially more destructive seismic events.

Idaho averages approximately 100 earthquakes per year, while Washington averages about 1,000 per year. Washington experiences roughly 900 more earthquakes annually.

Idaho is associated with Lost River, Lemhi, Beaverhead faults. Washington is associated with Cascadia subduction zone, Seattle Fault. 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 85% in Washington. Washington has a larger percentage of residents exposed to seismic hazard.

Idaho's most notable earthquake: 1983 Borah Peak (M6.9). Washington's most notable earthquake: 2001 Nisqually (M6.8). These historical events illustrate the seismic potential of each state.