PORTLAND, Ore. (KOIN) — It was January 26, 1700 — 321 years ago — that the last major earthquake along the 600-mile Cascadia Subduction Zone rocked what is now the Pacific Northwest.

Based on quakes over the last 10,000 years scientists believe there is a 40% chance of seeing another in the next 40 years.

Oregon’s geological hazards program coordinator said the pandemic was a major sign that people across the state are not prepared for the type of damage Cascadia could bring.


“As we saw in March with the pandemic, our public, our residents still need a lot of help and education on how to get prepared for these large-scale disasters,” said Dr. Althea Rizzo, the OEM Geological Hazards Program coordinator.

Rizzo said most damage and loss of life would likely be along the Oregon coast from the tsunami that would follow a major quake.

After the shaking, those waves would come about 15 to 20 minutes later. That makes it essential people have an evacuation plan in mind and supplies on hand in case The Big One hits.