The Tsunami Could Kill Thousands. Can They Build An Escape?

[brooklynite]

New York Times

OCEAN SHORES, Wash. — The 350 children at Ocean Shores Elementary School have practiced their earthquake survival plans, dropping under desks to ride out the convulsions, then racing upstairs to the second floor to await the coming tsunami.

Unless something changes, their preparations will most likely be futile.

The Cascadia fault off the Pacific Northwest coast is poised for a massive, 9.0-magnitude earthquake at some point, scientists say, a rupture that would propel a wall of water across much of the Northwest coast within minutes. Low-lying coastal neighborhoods in Washington, Oregon and Northern California would be under 10 feet or more of water, with the elementary school in Ocean Shores, Wash., facing an inundation that could be 23 feet deep.

The second-floor refuge students rush to in their drills stands 13 feet off the ground — in a structure that was not built to withstand a raging tsunami in the first place.

I've done vacation weekends several times at Ocean Shores and Long Beach. The drive out is on winding single-lane roads. Not easy to evacuate.

[BSdetect]

1. Buildings on floats may have a chance to ride the waves.

Impractical for very large structures but given the area's risk level at least some residential homes might be able to afford protection.

[Auggie]

2. Subduction events have the potential to be much stronger than strike-slip events ...

we have little idea just how strong a 9.0 magnitude can be for the simple reason that very few of us have ever experienced one.

The last huge earthquake, the last really “Big One” to hit the Pacific Northwest Coast, struck around 9 p.m. on Jan. 26, 1700 — 321 years ago.

Called Cascadia, the magnitude 9.0 quake caused the entire Pacific Northwest coastline to suddenly drop 3 to 6 feet and sent a 33-foot high tsunami across the ocean to Japan.

This was one of the largest earthquakes the Pacific Northwest has ever had, according to HistoryLink, and compares with two disastrous earthquakes: the March 27, 1964, Alaska earthquake, which measured 9.2 moment magnitude, and the May 21-22, 1960, Chile earthquake, which measured 9.5 moment magnitude.

https://www.seattletimes.com/seattle-news/northwest/on-this-day-in-1700-the-really-big-one-a-magnitude-9-0-earthquake-hit-western-washington/

[cinematicdiversions]

3. I remember reading a national Geographic from 1965 that covered the Alaska earthquake,

One can only imagine the devastation if that were to happen today.

[Auggie]

4. Yep. People will be shocked when (not if) it happens.

[FBaggins]

12. But not very likely to be people alive today

That fault zone reportedly has an 8.0+ event once every 300-900 years (with an average of about 580 years).

It's been just a hair over 300 years since the last one. So while it is possible that we'll see another in our lifetimes, it isn't particularly likely.

[Hortensis]

16. Right. Geologic time is a lot like biblical time.

[Auggie]

5. Magnitude 8.0 event is 33 times stronger than a 7.0

Essentially, each successive magnitude is 33 times larger than the last. That means a magnitude-8.0 earthquake is 33 times stronger than a 7.0, and a magnitude-9.0 earthquake is 1,089 (33 x 33) times more powerful than a 7.0 — the energy ramps up fast.

https://www.livescience.com/31464-earthquake-magnitude-explained.html

Been through a 6.9 (Loma Prieta) and that’s was pretty damn strong.

[Thunderbeast]

6. Some coastal communities are preparing.

Seaside, Oregon is moving schools to higher ground. Plans are in the works to build an evacuation platform with municipal services located on the deck.

When we stay on the coast at Rockaway, we know the evacuation route. We can walk about 10 minutes to higher ground. "Go bags" hang next to the door with emergency supplies.

Many vulnerable coastal towns are making preparations, but it is a long-term expensive proposition.

[ratchiweenie]

7. So many of those small towns along the Washington and Oregon coast are build almost on

the water and the highway is two lane along most of the coast from the tip of the Olympic Penninsula to Los Angeles. They are creating Tsunami escape routes all along the coasts but I cannot imagine what will happen if a 9.0 strikes.

[Lettuce Be]

8. We also used to pretend we could someone escape a nuclear blast

by getting under our desks at school.

[Hortensis]

15. :) Well, it would have helped a lot all over CA where I was then.

Large numbers of us in Los Angeles might only have needed to kiss our asses goodbye once and be done with it, but the way L.A. alone is spread out many others would have survived -- for better and worse.

[JanMichael]

23. That was such a joke. We knew it was futile.

Wichita Kansas was circled with Titan II missile silos.

[L. Coyote]

9. Oregon: Potential Statewide Effects from a Local Tsunami

In my county, a Big One tsunami would impact over 75% of residences.

Potential Statewide Effects from a Local Tsunami

Following is the number of housing units and population summarized by county that are located within the local tsunami inundation zone.
County Housing Units Population
Clatsop 16,238 26,214
Coos 15,870 31,439
Curry 7,559 12,466
Douglas 2,099 3,637
Lane 3,858 5,499
Lincoln 20,856 26,872
Tillamook 11,842 12,290

[PoindexterOglethorpe]

10. Single lane roads?

Surely two lanes. Or do you drive in one direction one part of the day, and the other the rest of the day?

[maxsolomon]

14. I've never been on a single lane road on the WA coast.

Unless it was a driveway. 2-lane blacktop.

There needs to be high ground within a 20-minute walk; providing that is what this article is about.

It won't be a perfect solution no matter what.

[Ferryboat]

11. I vacation on the Longbeach peninsula every year. More than a few of the locals

Have a escape pod in the backyard. Basically its a sphere designed to hold and sustain the occupants after the waters come ashore.

Floats, equipped with a transponder food and water. Japanese product. Around 10k.
Would hate to be the one who has to ignore the neighbors outside.

[Ex Lurker]

13. great if you happen to be at home when it hits.

if you're at work or at the store, you're out of luck.

[nolabear]

17. Seriously? Where can I find info on those?

(Guess who has a house in Ocean Shores…😄

[Ferryboat]

19. Nor sure where you can find out the info.

When we were researching retirement homes we came across a website promoting survival craft.

[nolabear]

18. I have a house in Ocean Shores.

Just bought it a few months ago as, you know, an escape from the horrible stressors of life these days. A place we can enjoy nature, kick back and relax, finally feel we can play a little in this miserable, catastrophe-riddled time.

So thanks a pantload. Oh, I know it’s not you; you’re being a helper. And tbh, this has been an enormous topic of conversation on the coast. The actual meetings, proposals, budget issues, and so forth, are hot items. Everyone is figuring the odds.

We’re on what passes for high ground and the house itself is three floors and sturdy as hell, so if any structure would be safe it would. But I guess going out to eat or driving or going to the beach or anything is out. So…cool. Cool.

[Ferryboat]

20. Goggle survival capsule

[nolabear]

22. I did. Woof!

I guess my old New Orleans “always have an ax in the attic in case you have to chop through to the roof” training might be useful after all.

[msongs]

21. log in required to read article.... nt