Geologists and civil engineers have broadly determined that the Pacific Northwest region is not well prepared for such a colossal earthquake . The earthquake is expected to be similar to the 2011 Tōhoku earthquake and tsunami , because the rupture is expected to be as long as the 2004 Indian Ocean earthquake and tsunami . The resulting tsunami might reach heights of approximately 30 meters ( 100 ft ) . FEMA estimates some 13,000 fatalities from such an event , with another 27,000 injured . It predicts that a million people will be displaced , with yet another 2.5 million requiring food and water . An estimated 1/3 of public safety workers will not respond to the disaster due to a collapse in infrastructure and a desire to ensure the safety of themselves and their loved ones . Other analyses predict that even a magnitude 6.7 earthquake in Seattle would result in 7,700 dead and injured , $ 33 billion in damages , 39,000 buildings largely or totally destroyed , and 130 simultaneous fires
2011 Tōhoku earthquake and tsunami
2011 Tōhoku earthquake and tsunami
Cascadia subduction zone