Is Seattle Earthquake ready? (Federal Way: crawl space, public schools, live)

[UnusualSuspect]

Originally Posted by burnhams

I read somewhere that the type of ground Seattle is built on makes earthquakes worst by amplifying it.

There are some areas of Seattle that could liquefy during an earthquake, but luckily, most of Seattle is NOT built on that kind of land. You can see the areas at risk here (select liquefaction). I think the places you most want to avoid are SODO, Pioneer Square, Interbay, and the area right around University Village.

[scottinpdx]

Originally Posted by UnusualSuspect

There are some areas of Seattle that could liquefy during an earthquake, but luckily, most of Seattle is NOT built on that kind of land. You can see the areas at risk here (select liquefaction). I think the places you most want to avoid are SODO, Pioneer Square, Interbay, and the area right around University Village.

Thanks for the info!

[daisylayc]

I saw something on TV yesterday and it is going to happen. You all need to realize it and do something about it. The buildings that Seattle has are OLD! There is going to be tsunamis as well. If you want to save yourself do it now. I have kids and would hate for them to go through something like that.

[AlohaHuey]

Originally Posted by daisylayc

I saw something on TV yesterday and it is going to happen. You all need to realize it and do something about it. The buildings that Seattle has are OLD! There is going to be tsunamis as well. If you want to save yourself do it now. I have kids and would hate for them to go through something like that.

You have to understand, there are different kinds of earthquakes. Nearly all will not cause a tsunami. The Cascadia fault is very dangerous and is quite far from Seattle (off the coast of WA/OR), but the big earthquakes that cause the kind of devastation seen in Japan are events that happen every 300-1,000 years. It's good to be prepared and know the risks, but packing up and fleeing isn't really a rational response.

[Hemlock140]

I was working a block from where the Cypress Freeway fell in Oakland on that evening in 1989. On a much smaller scale I felt what the people of Japan are going through, with family and friends out of contact, seeing and smelling the death and destruction. Now I work on the Seattle Waterfront, and drive home on the Viaduct every day. Sounds crazy I suppose, but you cannot live your life always afraid of things. If it's going to happen it will. Move to Nebraska where there are no earthquakes and a tornado gets you. Move to the Twin Cities and a bridge falls into the river.

[ay jayy]

A tsunami will not hit Seattle, It is protected by the olympic peninsula.

[eskercurve]

Originally Posted by ay jayy

A tsunami will not hit Seattle, It is protected by the olympic peninsula.

Not necessarily.

Seattle lies almost right on top of a fault that runs north-south and bisects a fault which runs east-west. At some point 1,000 years ago, there's evidence that a tsunami basically flooded Whidbey island.

However this wouldn't be your typical scenario tsunami where the ocean floor rises or shifts, causing the water level to rise. This would be a "sloshing" effect since Seattle rests at an inlet off the Strait of Juan de Fuca. Under the most likely scenario, the Duwamish river basin would drain from Harbor Island tilting, which would cause a rush of water out into the bay, and ricochet off the northern coast, which would cause waves up to 16 feet to reach the shore. And it would take two minutes for that to happen.

Here's some info:

What would a Seattle tsunami look like? | Seattle's Big Blog - Seattle Post-Intelligencer

And remember the Nisqually earthquake was a 6.8. That's pretty strong. And remember we are on the Ring of Fire. Mt St. Helens is proof.


Does this mean run for the hills? No. But it isn't a question of IF this would happen, but WHEN. Most likely something like this will happen again in the next 1500 years. So, i'm not packing up yet.

[AlohaHuey]

Originally Posted by ay jayy

A tsunami will not hit Seattle, It is protected by the olympic peninsula.

Tsunami waves "wrap" so the Olympic penninsula offers no real protection.

[Seacove]

Originally Posted by AlohaHuey

Tsunami waves "wrap" so the Olympic penninsula offers no real protection.

Is that true? Is there an animated simulation that shows that anywhere? I've looked for that sort of thing before and have not found one yet. If it "wraps", does that apply to Lake Washington as well since it's connected?

[swerver]

Does anyone know a source of info on building codes in the Seattle area with regard to earthquakes? Most of the talk is about tall buildings, but what about normal single family homes? Have the codes changed over the years, if so when? I am curious what if any improvements are required by code for single family homes, other than not building brick houses.