How the Landscape Across the Northwest Would Change After a Megaquake

The West Coast lives with a quiet but very real threat. A major earthquake along the Cascadia Subduction Zone could trigger widespread destruction across the Pacific Northwest and permanently reshape parts of the coastline.

New research warns that the damage would not stop at shaking and tsunamis. In some areas, the land itself could sink suddenly. That shift could cause an immediate rise in relative sea level, expand flood zones, and change where water flows and where communities can safely rebuild.

Here is what scientists say could happen.

What Is the Cascadia Subduction Zone?

The Cascadia Subduction Zone is a massive offshore fault system stretching from Northern California into British Columbia, Canada. It runs roughly 70 to 100 miles off the Pacific coast.