New study simulates what would happen if the ‘big one’ hit Western Washington

WESTERN WASHINGTON — Scientists are predicting in a new model what would happen if a tsunami hit Western Washington.

The simulator shows what would happen if a 9.0 earthquake hit the Cascadia subduction zone - also known as “the big one.”

The study estimates that the earthquake would generate a tsunami capable of submerging coastal areas as well as most of the shoreline in Puget Sound with several feet of seawater.

Geologists from the DNR conducted the study to help develop preparation and response plans for those who live in populated areas.

The last Cascadia rupture was 321 years ago, and experts now estimate a 10-17% chance that there will be another earthquake in the next 50 years.

Scientists say that tsunami waves would reach Whidbey Island within 1.5 hours of the earthquake, and it will take 2-4 hours to reach more inland areas of Puget Sound.

The study also estimates a high of about 13 feet at the Vashon Island Ferry Terminal and 3.7 feet in Elliot Bay.

See maps showing wave heights at other locations here.