Husband wants to move after coming across the "mega earthquake" article (Portland: rent, hotel)

[Silverfall]

Originally Posted by conlainhothuong

We decided that we will remain here, although I guess it will take awhile for all these news articles to die down before we can be comfortable again. Someone in a different forum suggested we look at portland maps where you type in the address and it will tell you your area's earth quake hazard risk. Found out ours was high. Oh well, whatever. Lets just hope that if it does happen during our lifetime, we wont be amongst the "13,000" casualties that the FEMA predicted. I do pray that if it does strike in the near future, that all my kids would be safe. I cant imagine them losing their little lives. Dont know how old they will be then, but still.

Look, why don't you just get educated and make some "mental preparations" to reduce your anxiety?

Unlike Indonesia, which had NO Tsunami warning system, we do. Beside the obvious fact that you would feel an earthquake on the coast so you would know the tsunami is coming, they have a warning system with sirens. The NOAA takes care of that system. That is different than the earthquake warning system they talked about in the article.

The tsunami-inundation zone is all along the coast. As long as you can move a mile in 10 minutes (which is the shortest estimated time for a tsunami to hit), you'd be fine. You also might not need to go a mile if you can go up. They actually have an app that shows the routes, so maybe get that and before you go to the coast, just mentally make note of where to go. The evacuation maps were designed for the worst case scenarios.

You can look at the numbers any way you want for your mental health, but they are estimating 13,000 for worst case scenarios, which with the current population of Oregon means that 99.7% of people will survive the big quake. You can focus on the .3% estimate for death or the 99.7% number for survival.

[PNW-type-gal]

The "13,000" prediction includes the entire zone from Northern California to BC, where the estimated population is around 10 million (3.6 million in the Seattle msa alone, 2.4 million in Portland area)

[CanuckInPortland]

Even the geologist who is the foremost expert on the Cascadia Subduction Zone said the "everything west of I-5" quote was hyperbole. Also, the prediction for "1 in 3 chance in 50 years" was just for the south part of the fault going(closer to the Southern Oregon Coast and Northern California)--the absolute worst case scenario is the historically rarer event of the entire fault line going(which is all based on estimations). That's the worst case scenario described in the article where basically the entire West Coast from Northern California to BC feels the shaking with a 9.0 quake.

I had friends in Japan who went through the 9.0 and they were much closer to the epicenter than a coastal quake would be from the populated areas of the Pacific Northwest. There was little structural damage, road damage was on highways built on coastal/river soil, most damage was right at the coast from the tsunami. But within a year they'd already rebuilt a lot of the damage(this wasn't in the worst hit place though nor was it by the nuclear power plant), but it was still close. While Japan has a much stronger set of building restrictions--people dealt with it, and realize the possible danger they will always face and go on with their lives.

[BaseLineRoad]

Originally Posted by CanuckInPortland

I had friends in Japan who went through the 9.0 and they were much closer to the epicenter than a coastal quake would be from the populated areas of the Pacific Northwest. There was little structural damage, road damage was on highways built on coastal/river soil, most damage was right at the coast from the tsunami.

The Japanese have been building with earthquakes in mind, however. Much of our infrastructure in Portland wasn't built to withstand shaking. I doubt that the same earthquake would in Portland and Japan would look at all the same.

Here's an article from 2014 that addresses exactly that:

Earthquake planning in Multnomah County: What if 'the big one' hit today? | OregonLive.com

[CanuckInPortland]

Originally Posted by BaseLineRoad

The Japanese have been building with earthquakes in mind, however. Much of our infrastructure in Portland wasn't built to withstand shaking. I doubt that the same earthquake would in Portland and Japan would look at all the same.

Here's an article from 2014 that addresses exactly that:

Earthquake planning in Multnomah County: What if 'the big one' hit today? | OregonLive.com

The earthquake in Kobe in 1995 destroyed a lot of buildings and highways and this was after Japan had already enacted higher standards for earthquakes. There was some increase in building standards in the 2000s, but many of the buildings that survived the shaking of the Tohuku quake weren't built after this time. The reason the Kobe quake was worse in terms of structural damage from the quake itself(most of the Tohuku damage was the tsunami)--was because the quake that struck Kobe was right next to it while the Tohuku quake was some distance from land.

Now, yes a quake would hit Oregon and Washington harder than a similar one in Japan--though given when a quake could hit the Northwest(anytime from right now over the next hundreds of years)--there's a chance to retrofit buildings or assess where the biggest risks are. In a massive tsunami scenario, much of the coast is screwed unless you want to start building concrete bunkers as housing there rather than quaint wooden homes. Damage inland from a 9.0 quake under the coast would be massive, but at the same time the further you get away from the epicenter, the less damage you're going to get. A 6.5 quake just under Portland could cause plenty of damage on its own. Older brick buildings aren't going to fare well, newer construction will do better, but not everything is going to necessarily collapse. Even the aftermaths of other mega-thrust quakes shows older buildings that were somehow still standing.

The takeaway though it that it might not be too late to do something that might prevent possible catastrophic loss of life to some degree.

[pecivil]

some factoids to help this thread.

Portland is way too far from the coast to be directly affected by the Tsunami.

A 9.0 EQ on the Subduction Zone will be the real issue for everything 5 miles away from the coast or farther. It will shake everything like you have no idea, and for a really long time. Probably over 3 minutes.

Low rise wood framed bldgs are the safest kind of bldg to be in. They can move, deform yet still stay together for the most part. But considering a 9.0 event, most structures have the potential to be on the ground, because of the duration of shaking. BTW it is almost impossible for a large apt bldg to not have ANY anchorage from foundation to wood. There is something there.

It is extremely east to determine the seismic ground accelerations at a given sight to see what you have. Just need an address.

[conlainhothuong]

Originally Posted by pecivil

some factoids to help this thread.

Portland is way too far from the coast to be directly affected by the Tsunami.

A 9.0 EQ on the Subduction Zone will be the real issue for everything 5 miles away from the coast or farther. It will shake everything like you have no idea, and for a really long time. Probably over 3 minutes.

Low rise wood framed bldgs are the safest kind of bldg to be in. They can move, deform yet still stay together for the most part. But considering a 9.0 event, most structures have the potential to be on the ground, because of the duration of shaking. BTW it is almost impossible for a large apt bldg to not have ANY anchorage from foundation to wood. There is something there.

It is extremely east to determine the seismic ground accelerations at a given sight to see what you have. Just need an address.

I dont fill comfortable giving my exact address on here, but you can look up Easton Ridge .

And thanks everyone for calming my nerves. It gets better, just trying not to think about it too much. Only thing we can do now is stock up on water, dried goods, etc.

[whirnot]

I read that article and it gives compelling evidence that it will happen someday, but no one knows for sure when. One of the statements was "everything west of I-5 will be toast." Would I be concerned? maybe, but I am on the other side of the mountains. But if you discuss it further, I can tell you from a disaster standpoint Denver is not better. Beside big snow storms, they sometimes have flooding, several have been killed this year by lightning, tornadoes are not uncommon and the big one, Hail.

My homeowners insurance went from $1400 per year, 50 miles north of Denver to $450 per year in Central Oregon, for similar value. That is a good barometer of risk. I have been stranded by big snow, and have seen three tornadoes.

[mwruckman]

Originally Posted by PNW-type-gal

The "13,000" prediction includes the entire zone from Northern California to BC, where the estimated population is around 10 million (3.6 million in the Seattle msa alone, 2.4 million in Portland area)

One part of the Pacific NW Coast tailor made for a Tsunami disaster is the barrier islands on the Washington coast and the funnel like character of Grey's Harbor and Willapa Bays. Places like Ocean Shores, Westport, and Long Beach would be erased and if it happened on a warm summer day as many as 100,000 might just vanish. Places like Hoquiam, Aberdeen and Raymond would not fare well either. Looking to the north I'd worry about Port Angeles, Victoria BC and Vancouver BC

[Billy_J]

Have you been on a boat? Rocking back and forth?

Well that is what an earthquake is like. Things just fall down which are not attached. A brick house can crumble... But wooden homes stay put together - like a wooden boat! (But the things inside the boat may fall off the shelf onto the deck.)

With that said, during an earthquake, stand under a doorway. Then nothing will fall on your head - you will be safe. Not really a big deal IN REALITY!