The Really Big One

Whoa. Did you all see Kathryn Schulz’s article in The New Yorker: “The Really Big One”?

It’s an extremely well-written — indeed, captivating — article about an earthquake zone I’d never heard of, north of the San Andreas fault, where the continental plate is hung up on the oceanic plate and being held back and compressed.

The last very big earthquake appears to have hit that region in the year 1700 AD. Here’s what’s expected when the next big one — for which we appear overdue — hits:

When the next very big earthquake hits, the northwest edge of the continent, from California to Canada and the continental shelf to the Cascades, will drop by as much as six feet and rebound thirty to a hundred feet to the west—losing, within minutes, all the elevation and compression it has gained over centuries. Some of that shift will take place beneath the ocean, displacing a colossal quantity of seawater. … The water will surge upward into a huge hill, then promptly collapse. One side will rush west, toward Japan. The other side will rush east, in a seven-hundred-mile liquid wall that will reach the Northwest coast, on average, fifteen minutes after the earthquake begins. 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.” In the Pacific Northwest, everything west of Interstate 5 covers some hundred and forty thousand square miles, including Seattle, Tacoma, Portland, Eugene, Salem (the capital city of Oregon), Olympia (the capital of Washington), and some seven million people.

I mean, wow. Now I know how I would start a disaster or postapocalyptic novel, if I were writing one.

A grown man is knocked over by ankle-deep water moving at 6.7 miles an hour. The tsunami will be moving more than twice that fast when it arrives. Its height will vary with the contours of the coast, from twenty feet to more than a hundred feet. It will not look like a Hokusai-style wave, rising up from the surface of the sea and breaking from above. It will look like the whole ocean, elevated, overtaking land. Nor will it be made only of water—not once it reaches the shore. It will be a five-story deluge of pickup trucks and doorframes and cinder blocks and fishing boats and utility poles and everything else that once constituted the coastal towns of the Pacific Northwest.

Unbelievable. Or rather, unthinkable. Or unfortunately, everyone in that region appears to be treating the possibility as both unthinkable and unbelievable, because nothing much is being done to help anybody survive this disaster when it does occur. Which it will; it has to; you can’t block an entire continental plate forever; eventually it’ll have to straighten out. Boom. Tomorrow or in a hundred years, who knows, but if the plate’s already been hung up this long, well, it’s definitely under a lot of pressure.

Of course the whole region was developed before anybody even knew about the fault or how it works. But we’ve known about it for a couple of decades now, and no one has even troubled to put in an early warning system — the kind that Japan has — the kind that would let authorities shut down power stations and warn hospitals and so on.

Anyway, yeah, okay, now I’m happier at being practically on top of the New Madrid fault. At least if this one lets go, we won’t get a tsunami. If I lived in Seattle, well, honestly, after this article, I’m just glad I *don’t* live in Seattle. Any of you all who *do* live in the Pacific Northwest, well . . .

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8 thoughts on “The Really Big One”

  1. Japan put in its early warning system in 2007, and California just got funding for one in December of last year, so I’m not sure “no one has even troubled” is really fair yet. Politics is slow, and denial of a disaster for which full preparation is difficult-to-impossible, and which after all might happen centuries hence, is really tempting.

    It sounds like they do have an earthquake code for new construction. If things hold off then maybe the idea will sink in enough to get an EEWS funded and evacuation routes to be taken seriously.

    But while that will be worthwhile, I doubt that the area’s going to either be depopulated or really prepped for a once-in-more-than-a-lifetime disaster. That strikes me as a hard problem. Which I’m sort of glad to be a couple thousand miles from.

    (…not counting the fact that I’m going to Vancouver tomorrow for a few days. If the Big One hits while I’m there, raise a glass to the spirit of ironical retribution. Likewise if the Midwest is hit by an asteroid strike or something first.)

  2. Yes, I don’t think anything we can do is going to save many people in that area, or any construction in the tsunami region . . . but I would hope to see planned evacuation routes at least! People talk about tornadoes in the Midwest, but seriously, a tornado hits, what, a couple square miles at most? If you wrap its path up and pretend it was all one parcel. This earthquake/tsunami thing is way, way different.

    And, sorry! I bet it will cross the back of your mind once or twice while you’re in Vancouver! Probably that would have been a better article to read after you got home again.

  3. Eh, it’ll give me something to catastrophize about between the plane crashing and the ship hitting an iceberg. ;-) The part of my brain that does numbers recognizes that something with a 37% chance of happening sometime in the next half century probably won’t hit right during the three days I happen to be there.

    (Granted, another part of my brain is telling it “shutupshutupshutup you’ll jinx us” and looking for a number of pieces of wood to knock.)

  4. Seattle is relatively safe from a Cascadia tsunami: most of the energy would dissipate on Whidbey Island 30 miles north of here. We are vulnerable to smaller tsunamis within the sound, say from the Seattle fault. There would be essentially no warning in that case. The first wave would hit before the quake subsided.

  5. I wonder how much California would be impacted by that one? I may live here but sometimes I do think it should all fall into the Pacific (preferably while WE’re out of state).

    I read a book once on the last New Madrid quake, and the damage may not have been caused by a tsunami, but was darned impressive…. now what was it…(invokes Amazon).. WHEN THE MISSISSIPPI RAN BACKWARDS, that’s it! You aren’t living all that near the river, are you? And I hope your building codes take earthquakes into account.

  6. Well, we’re seismically upgrading all our schools, so that’s something . . .

    Don’t worry; we’re very aware of impending disaster here in Vancouver. Pretty sure that Vancouver Island will save us from the tsunami, but all our escape routes are over bridges, so that’s a bit of a problem.

    A couple of years ago the BC Emergency Info site had a brilliant “Are You Prepared for the Zombie Apocalypse” campaign to try to get more people on board with general emergency preparedness. I wish the site were still up: it went through a whole three-day disaster scenario, except using zombies attacking instead of an earthquake as their example. Very clever.

    Everytime there’s a little earthquake somewhere near, we’re all thrilled, because it means a little more pressure is being relieved! Maybe there will just be a bunch of little ones instead of The Big One. We can always hope, right?

    (I should go update our 72-hour kit; I suspect our fruit bars are expired!)

  7. Welllll it’s good to think that Seattle has a barrier island, but still, sounds like a Cascadia quake would be a significantly bigger deal than a New Madrid quake — even though New Madrid is a pretty serious fault, too. We’re personally way far away from any river and in fact up on a (low) mountain, and we don’t have gas, just electric, so if we didn’t get crushed by the houses collapsing, we’d be okay. My guess is all the limestone in this region means we’re not likely to have the ground liquefy like that article talked about, though I’m not sure what factors would lead to something like that, either.

    Kim, I think the “Are you prepared for the Zombie Apocalypse?” campaign was a brilliant idea. Gold star to whoever came up with that! Yes, if I were you, I’d be really pleased to have a series of little quakes, the more the better.

  8. I’ve been meaning to purchase earthquake / disaster kits, but this article just cinched it.

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