To the north of California’s famous San Andreas fault is a less known, but possibly more deadly, fault line. The Cascadia subduction zone runs some 700 miles from northern California to Vancouver.
In a deeply reported article for The New Yorker, Kathryn Schulz tells the tale of how this fault lies dormant for periods of 243 years, on average, before unleashing monstrous tremors. The Pacific Northwest is 72 years overdue for the next quake, which is expected to be between 8.0 and 9.2 in magnitude.
At the upper end of that scale, Schulz notes, we would experience “the worst natural disaster in the history of North America.” (The major 2011 earthquake in Japan was a 9.0, killing more than 15,000 people.)
The Federal Emergency Management Agency (FEMA) already has an emergency response plan for when this earthquake hits. Parts of FEMA’s quake expectations are truly terrifying. As Schulz writes:
FEMA projects that nearly thirteen thousand people will die in the Cascadia earthquake and tsunami. Another twenty-seven thousand will be injured, and the agency expects that it will need to provide shelter for a million displaced people, and food and water for another two and a half million.
These projections are based on a scenario that has the earthquake striking at 9:41 a.m. February 6. (The agency isn’t trying to predict the future or saying that the earthquake will definitely occur then, they just need a date to plan around.) The toll would be far higher on a warm day, when more people — often huge crowds of people — are at the beach or in the water.
When the quake does occur, its severe effects and the impacts of the following tsunami (“It will look like the whole ocean, elevated, overtaking land”) will be felt all the way from Canada to Sacramento, in densely populated cities like Seattle and Portland.
What’s more, the Pacific Northwest is not earthquake ready. Buildings aren’t retrofitted properly and there aren’t many effective emergency warning systems or escape plans in place.
The aftermath will be devastating. Schulz writes:
By the time the shaking has ceased and the tsunami has receded, the region will be unrecognizable. Kenneth Murphy, who directs FEMA’s Region X, the division responsible for Oregon, Washington, Idaho, and Alaska, says, “Our operating assumption is that everything west of Interstate 5 will be toast.”
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