Oregon vs Washington Earthquake Risk

Oregon and Washington share the same risk score of 8/10 (High). Both states face similar levels of seismic hazard, though the specific fault systems and earthquake characteristics differ.

Oregon averages approximately 500 earthquakes per year, while Washington averages about 1,000 per year. Washington experiences roughly 500 more earthquakes annually.

Oregon is associated with Cascadia subduction zone, Klamath graben. Washington is associated with Cascadia subduction zone, Seattle Fault. These fault systems determine the type and frequency of seismic activity each state experiences.

In Oregon, approximately 80% 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.

Oregon's most notable earthquake: 1993 Scotts Mills (M5.6). Washington's most notable earthquake: 2001 Nisqually (M6.8). These historical events illustrate the seismic potential of each state.