Risk of Natural Disaster: Does It Affect Your Decisions

[jyl]

Timely topic, I think.

Over here in the PNW, earthquakes are the main natural disaster - other than wildfire, for rural areas.

Having been in multiple large earthquakes while living in California, I’m not that concerned about them. At least as far as personal risk of death/injury, or risk of losing house/contents, goes. I have bolted the house, carry earthquake insurance, have lots of food, 80 gallons in the strapped-down hot water heater, etc.

However, our particular “Big One” earthquake risk comes with . . . tsunami risk. The big fault is the “Cascadia subduction zone” about 100 miles offshore, and in the event of a CSZ rupture tidal waves will hit the Oregon and Washington coast about 15-20 minutes later. Up to 60 foot tidal waves, at the extreme. Which is why all up and down the Oregon coast there are signs for the closest tsunami escape routes; the sirens go off, you head immediately to high ground. Stay in your lovely oceanfront home, and you may die.

Of course, who knows when the next CSZ rupture will come. It is overdue, per historical geological data, but human lifetimes are short, probability of next CSZ rupture in my lifetime and my kids’ lifetimes is . . . 10%? 30%?

So, I’ve been looking at places to get a second home, with an eye towards eventual retirement and until then, being able to take a break from city life. Here’s a tsunami inudation model map of one possible area:



It looks like, most of the spit will be inundated, some areas probably violently so, and naturally those parts are where most of the houses are. Can you get to high ground in 10-15 minutes? There’s like one road; I guess you could flee on foot, run east, hope to reach a gray shaded area.

I was pointing out to my daughter last night that, if we had a second home there, our entire family could potentially be wiped out and there goes the bloodline. She said no problem, her brother will simply be barred from ever visiting.

Question is: what would you do? Would you take the risk of living there? Staying there part time? Or avoid?

[Paul T]

2 of 3 properties I own are coastal, so obviously I haven’t let it impact my decision making, lol….but I do think about the asymmetric risk there often. So far, knock on wood, we’ve been very fortunate with weather events. I suppose it’s only a matter of time though. I play around with the NOAA maps a bit to see what various flood levels will do when looking at places, but in the end, anything can happen as it seems we have “once in 500 years” events every year these days.

[cockerpunk]

best reasons to stay in the mid west IMO. we do get tornados, but they are super local in terms of damage, and extremely rare. we are also basically climate change proof up here too. its absolutly one of the reasons why i stay.

[vash]

I talked to a Geologist professor at a tunneling seminar. he told me the geological features on the west coast are made up of rocks that are relatively weak. so he thinks that is why our earthquakes tend to be on the less extreme side of that event. he said the big USA earthquakes historically are on the east coast.

having said that. I like where I live, but when I RETIRE, that will change. I think losing my stuff now, versus losing my stuff when I am 78 years old are two vastly different events. I will move to a more stable enviormant then. no wildfires, no earthquakes.

with my luck, I'll get a killer bee invasion. hahah..

[Bill Douglas]

Fairly much everything I own is on the edge of the sea. And although I live in one of the most earthquake towns around I don't care. It's kind of like being a fish in a large school of fish. You always feel it will be someone else that gets it in the neck.

[Noah930]

Originally Posted by jyl

Of course, who knows when the next CSZ rupture will come. It is overdue, per historical geological data, but human lifetimes are short, probability of next CSZ rupture in my lifetime and my kids’ lifetimes is . . . 10%? 30%?

There was an article (maybe in Vanity Fair?) a few years ago about this fault line and the subsequent tsunami. IIRC, the risk in your (and your children's lifetimes) was fairly high. As in, it will likely happen in that timeframe, though obviously nothing is 100%.

The article gave a worst case scenario that everything west of I-5 would be leveled. I-5 (as it runs double-decker through Seattle) would likely collapse in locations, much like the Bay Bridge did. The entire area of Cannon Beach (OR) was doomed. No way to evacuate everyone there to higher ground in 15-30 minutes, and there are no tall buildings for escape, either.

[Noah930]

I do factor in climate change when considering where to move. We're moving to coastal New England soon (for family reasons). It's romantic to do so, but I have no serious desire to own an oceanfront home. With rising sea levels and possibly worsening hurricanes (though New England typically/historically does not get hurricanes), no way do I want the Atlantic Ocean to come crashing through my backyard.

[id10t]

Much prefer our hurricanes to anything else anyone deals with. No other disaster is nice enough to give a week or two warning before coming to crash the party. And being well inland in Florida (60-80 miles from the coast) and not near the local rivers (10+ miles away) hurricanes don't bother me much.

[GH85Carrera]

Here is Oklahoma, we like hurricanes, as we just get a nice heavy rain. It sucks for Texas,. but is great for us.

Tsunamis are a zero percent chance.

We have had a few earthquakes and a 4.8 shook the house with zero damage. Now that the oil well waste water disposal wells are limited too stable areas, earthquakes are mostly a thing of the past.

Tornadoes only hit a very small area. Draw a thin pencil line on a map, and that area may be destroyed, but just 1/4 mile away is full civilization. With the weather radar and storm chasers all three TV stations track the tornadoes from start to finish, block by block. Anyone watching the weather knows to get to a safe spot if they are coming at us. Our cell phones warn us of the possibility of a tornado. Just be weather aware and one has plenty of time to get to a safe area of the house. We have a tornado shelter and room for the dogs and us. The shelter is registered with the city, and the fire department know to come look for us if a semi has landed on the house.

My mom was born and raised in Oklahoma She never saw one, even at a distance, and he parents never saw one, and the lived to be in their late 70s. We had one hit 1.5 miles south and it was just a F2. Not much damage to the area it hit.

So no, I do not worry about natural disasters at all. Zombies don't exist so I don't worry about them either.

[Rusty Heap]

You live everyday, and only die once.

[GH85Carrera]

Originally Posted by Rusty Heap

You live everyday, and only die once.

Yep, but everyone seems to want to live as long as possible, at least I do.

[jyl]

Originally Posted by Noah930

There was an article (maybe in Vanity Fair?) a few years ago about this fault line and the subsequent tsunami. IIRC, the risk in your (and your children's lifetimes) was fairly high. As in, it will likely happen in that timeframe, though obviously nothing is 100%.

The article gave a worst case scenario that everything west of I-5 would be leveled. I-5 (as it runs double-decker through Seattle) would likely collapse in locations, much like the Bay Bridge did. The entire area of Cannon Beach (OR) was doomed. No way to evacuate everyone there to higher ground in 15-30 minutes, and there are no tall buildings for escape, either.

Cannon Bch will be inundated to at least a few blocks inland, in a “small / medium” CSZ rupture (wipe out most of the town’s structures and public services, but a reasonably mobile person has a good chance of getting to safety on foot given 10-15 min warning) or most of the way into the foothills of the coast range, in a “large / XL” rupture (wipes out everything and everyone, pretty much). I’m not worried about the L/XL events as they historically are once per a couple thousand year events, but the S/M events are the every few-to-several hundred year events, and the last one was in the 1700s.

https://pubs.oregon.gov/dogami/tim/Clat09_CannonBeach_Plate1_onscreen.pdf

To find more maps, see index map then the particular map you need

https://www.oregon.gov/dogami/pubs/Pages/tim/p-TIM-overview.aspx#TIMpubs

The effect in Portland will be roughly a magnitude 6+, according to maps I’ve seen. The CSZ can produce magnitude 9 earthquakes at the fault, but that’s some 200 miles and a mountain range away from Portland.

[masraum]

People have short memories. Folks down in Cali that build in land slide and wild fire areas.

In Japan, folks built along the shore despite there being "signs" (carved stones) left by other folks all up and down the coast that said "don't build below this sign".
Then there are lots of active volcanos that are settled around (super fertile soil near volcanos is a big driver, I believe). Those folks get wiped out in eruptions.

[varmint]

Pompei was 65 miles from Vesuvius.

I live 70 miles from Mt Augustine.



There’s no place on earth totally safe. Grew up in the Midwest with tornados and blizzards. Then Los Angeles with earthquakes, staggering taxes and race riots. It’s going to go off eventually. That and the bears.

[flatbutt]

The only thing I fear is a wild fire. One came close last year and made me realize there's fark all I can but grab a bug out bag, a pistol and some rounds and skedaddle.

[Evans, Marv]

I've read damage from a CSZ rupture could be devastating far inland. A potential 9 magnitude earthquake would do unimagineable damage. With climate change, it's hard to figure out where to live and be safe from everything. I figure it's just about the best you can do to determine escape routes anywhere you live and hope something won't happen in your lifetime. I feel fairly secure where I live from everything but fire and earthquakes. I'm prepared as well as possible for the fires, and I've been through several earthquakes, so they don't scare me anymore. Tidal waves, floods, and dams breaking are a whole nother danger.

[Tobra]

not at all

[Alan A]

Have a generator. Does that count?

[jyl]

Originally Posted by Evans, Marv

I've read damage from a CSZ rupture could be devastating far inland. A potential 9 magnitude earthquake would do unimagineable damage. With climate change, it's hard to figure out where to live and be safe from everything. I figure it's just about the best you can do to determine escape routes anywhere you live and hope something won't happen in your lifetime. I feel fairly secure where I live from everything but fire and earthquakes. I'm prepared as well as possible for the fires, and I've been through several earthquakes, so they don't scare me anymore. Tidal waves, floods, and dams breaking are a whole nother danger.

It’ll be a 9, but 200 miles from Portland.

Yeah, on the coast, it’ll be devastating. Whatever the tsunami doesn’t take, the earthquake will.

Then it’ll be important to have cash to pick up lots for cheap, vulture style.

[LWJ]

I absolutely think about natural disasters. Too much, I am certain. In Oregon, Coastal erosion is a legit concern on many miles of the coast. Inland? Not an issue. The Tsunami conclusion about being on a spit is correct. You can all die in a quick event. I think this is good decision making.