Washington State Mudslide

[jamesp]

pic's are probably deceiving but the hillside doesn't look very steep or high, so the size of the slip is totally out of proportion. Crazy. Its on the outside of the river bend, was the river undercutting it?

re the comments about blaming logging in the 60s? Seriously? Nothing grew back in the 50 years since?

[Cruiser]

Pics remind me of Slumgullion Pass down by Lake City.

[grrrr]

Some family friends live in Oso, can't tell if they are under that or not. Bummer.

[GeezerSteve]

pic's are probably deceiving but the hillside doesn't look very steep or high, so the size of the slip is totally out of proportion.

It's huge. The toe of the slide covers a small housing community. The slide happened around 11AM on Saturday, so people home rather than at work in or in school. Below is a pic showing the housing community that is now under a big pile of mud.

Its on the outside of the river bend, was the river undercutting it?

Yes, see this analysis.

[BCMtnHound]

Looking at the pic that Jamal posted, you can make out the headscarps of several previous historical slides downstream along that terrace. It is troubling that previous terrain stability assessments did not identify the risk, or that the risk was ignored in the course of development planning. I've had to deal with a few slides on terraces that share similarities as this, but thankfully nothing at this scale or impact; if there is one aspect of my work that gives me shivers is contributing to an event of this magnitude. Our hydrologists & geotechnical professionals typically are on speed dial from now until the end of the freshet.

Vibes to everyone affected.

[GeezerSteve]

The area that was wiped out had homes on it as far back as 100 years ago. I doubt anyone anticipated a slide of this magnitude. FWIW, the area has been the subject of several studies re slide potential because it runs along a major earthquake fault.

[BCMtnHound]

Don't mean to come off like a douche, but the frequency interval of such an event and that human habitation has been relatively safe there for 100yrs doesn't really hold water - literally. And the risk assessment done 100yrs ago for a rural area with a couple of homes is not the same as subdivision development that has occurred in the area over the past few decades.
I am not immune from the issue from the landowner perspective either - my wife came into our relationship having a property on a very active debris torrent creek on Lillooet Lk. There has been a number of large torrents in the last couple of years (both increasing in frequency and intensity), with the last statement by the geotechnical is that it is only a matter of when, not if, a fatality will occur in the development. We are awaiting a new report to be completed sometime this summer that may condemn several properties in the development, including ours. She was understandably upset that she may lose a lot of her investment, but I reminded her about that cost vs the cost of a torrent event happening while we are sleeping in the cabin. And there are others involved that have multi-million $ 'cottages' that may be impacted (and all the political wrangling that goes with such investments when faced with a damning terrain stability report). My first question was who in the regional district approved the subdivision (actually a land corp) back in the 70's in the first place - the creek and associated fan was known in early engineering reports when the FSR was first constructed along the lake several decades before. Not an easy issue to address.

[GeezerSteve]

Don't mean to come off like a douche, but the frequency interval of such an event and that human habitation has been relatively safe there for 100yrs doesn't really hold water - literally. And the risk assessment done 100yrs ago for a rural area with a couple of homes is not the same as subdivision development that has occurred in the area over the past few decades.

Who said that it did? Not me. Read my prior posts. The slide potential in that area has creeped me out for the 28 years I've been driving that road. (That can also be said re many other places I've seen homes, including BC.) And what "recent subdivision development" are you talking about? AFAIK, those lots were platted before WWII, possibly as early as 1915.

Maybe you didn't get that I was responding to this:

It is troubling that previous terrain stability assessments did not identify the risk, or that the risk was ignored in the course of development planning.

Neither. The facts are this: The risk of huge landslides in the area was indeed identified and announced. See my comment re the studies re the major earthquake fault. But people decided to build there anyway notwithstanding the risk, just as people in BC and in flood plains all over the world build homes in risky areas. Re "development planning," the lots upon which the homes were built were platted before WWII, long before "development planning" existed outside a few cities. And there was no way to take those properties out of play more recently without compensating the owners. (We have this thing here in America called the Fifth Amendment.)

[BCMtnHound]

The facts are this: The risk of huge landslides in the area were indeed identified. See my comment re the studies viz the major earthquake fault. People decided to build there anyway, and Snohomish County let them. Unincorporated SnohoCo is a place with lax land use standards. That's what the people there want.

That is troubling. I can understand if locals who buy land wanting lax permitting laws for building in such an unsafe zone solely for their own personal use (even if I don't agree with it), but who is responsible for informed consent when that property/house is resold? I wonder if the county will change its zoning and permitting laws as a result of this tragic incident?

[NoPostholio]

Vibes to those affected by this -
Was looking at google earth trying to pinpoint area to see what kind of development was engulfed - anyone know if this is close?


And if so, there is a fascinating array of encroachment into nature - esp this right over a couple hills S from there. Someone please find this on google earth and explain wtf that is

[Hugh Conway]

NPH - lradius around a road would suggest highline loggin'?

That is troubling. I can understand if locals who buy land wanting lax permitting laws for building in such an unsafe zone solely for their own personal use (even if I don't agree with it), but who is responsible for informed consent when that property/house is resold? I wonder if the county will change its zoning and permitting laws as a result of this tragic incident?

This is 'murica not some socialist republic.

[GeezerSteve]

That is troubling. I can understand if locals who buy land wanting lax permitting laws for building in such an unsafe zone solely for their own personal use (even if I don't agree with it), but who is responsible for informed consent when that property/house is resold? I wonder if the county will change its zoning and permitting laws as a result of this tragic incident?

I edited the post to which this responds after doing a bit of research which suggests that the subject lots were platted between 1915 and 1940 as residential lots. The 5th Amendment of the U. S. Constitution has been interpreted such that a downzone of property that renders the property less valuable is a "taking" for which the governmental entity is required to pay compensation. (I am simplifying.) Whenever a governmental entity -- in this case Snohomish Co. -- downzones, it takes the risk of getting hit with compensation claims that it cannot afford to play. So, the county instead warns the owners -- which certainly happened here -- and the owners take their chances.

Re disclosure from seller to buyer, the law typically does not require the disclosure of facts published for the world to see. AFAIK, every landowner in this valley knew and talked about the nearby earthquake fault and the possibility of a major slide. Millions of homes all over the world are in flood plains. Thousands of BC houses are in slopes that could turn to mush. Erosion happens. And when it happens like this, the irrationality of people's choice of building sites makes it no less tragic. I would not build there. My home is on the top of the West Seattle moraine -- but it's also proximate to the Seattle Fault. There are no risk-free building sites.

[RootSkier]

The 5th Amendment of the U. S. Constitution has been interpreted such that a downzone of property that renders the property less valuable is a "taking" for which the governmental entity is required to pay compensation. (I am simplifying.)

Regulatory takings aren't really my thing*, but I thought such planning efforts only constituted a taking if the regulation deprives the property of all economically viable uses.


*I am, however, out of town doing depos in a more garden variety takings case right now.


Edit: ++vibes++ to those affected by this shitstorm.

[NoPostholio]

NPH - lradius around a road would suggest highline

Thanks, but found it - all those shiny red towers and nice roads were freaking me out. Radio base makes sense though

http://en.wikipedia.org/wiki/Jim_Cre..._Radio_Station

So I must be in wrong spot for that slide - if hudge naval base was just over hill to the S that was bound to come upon the news.

[plugboots]

And if so, there is a fascinating array of encroachment into nature - esp this right over a couple hills S from there. Someone please find this on google earth and explain wtf that is

I don't know what "that" is, but the area that got engulfed is just East of Oso. The Steelhead Dr. area in the river bend on the North side of 530 has been obliterated.

[cat in january]

Leo, has anything been heard from the woman or her son?

[GeezerSteve]

Regulatory takings aren't really my thing*, but I thought such planning efforts only constituted a taking if the regulation deprives the property of all economically viable uses

Yup, I misspoke, but that's what these landowners would have argued. Those lots had no economic value other than as residential building lots. It also would have been politically difficult to declare those lots unbuildable. These issues get replayed over and over in rural America and the typical play is to warn the landowners of the risk and let them build.

[NoPostholio]

I don't know what "that" is, but the area that got engulfed is just East of Oso. The Steelhead Dr. area in the river bend on the North side of 530 has been obliterated.

thanks plug - that helped me find it. I was too far west - those were some fairly large houses in that development - again vibes to those in the area affected. Shame that the mtns give so much but also take back at their mercy.

[jamesp]

Yup, I misspoke, but that's what these landowners would have argued. Those lots had no economic value other than as residential building lots. It also would have been politically difficult to declare those lots unbuildable. These issues get replayed over and over in rural America and the typical play is to warn the landowners of the risk and let them build.

the same discussion happens after every flood event also. The towns/counties/cities don't want to tell people not to build because then they miss out on property taxes, increased population etc. Its a conflict of interest because they are approving their own revenue streams via development, but then compensation when shit hits the fan (clean-up costs etc) are picked up by the state or federal gov'ts up the chain. There isn't any good way to resolve unfortunately.

[NoPostholio]

and all long eastern seaboard hurricane Mcmansions ville - another sandy/Irene and there will a lot more thought about how close you really need to be to the ocean when Cat 5 storms roll through twice a decade. Weather is gonna continue to show its teeth, question is how quick will we react.

[spook]

dude it was funnier when only 8 were missing. do a line, or whatever you lawyers do now to chill.

[KQ]

the same discussion happens after every flood event also. The towns/counties/cities don't want to tell people not to build because then they miss out on property taxes, increased population etc. Its a conflict of interest because they are approving their own revenue streams via development, but then compensation when shit hits the fan (clean-up costs etc) are picked up by the state or federal gov'ts up the chain. There isn't any good way to resolve unfortunately.

But in some cases they do set certain requirements if you are going to insist on building in a flood plain. I have two marks on my property - the "100 year flood plain" and the "500 year flood plain". The first spot I picked to build my barn was in the 100 year flood plain. The county highly discouraged it and told me if I went ahead with it I'd have a lot of hoops to jump through. Granted that was a barn and not a home but it was the same for my neighbor down the road when he went to build his home.

Also, didn't South or North Carolina ban ppl from rebuilding on one of their barrier islands after a particularly nasty hurricane a couple years back? I seem to recall it had something to do with the government not wanting to have to build a new road and service ppl who insisted on living on the edge.

[RootSkier]

Also, didn't South ...Carolina ban ppl from rebuilding on one of their barrier islands ....

http://en.wikipedia.org/wiki/Lucas_v...oastal_Council

If you don't understand the end result, it's OK. Neither does anyone else.

[GeezerSteve]

14 confirmed dead, 176 missing

[cat in january]

Morning news has it up to 24 dead and 150 unaccounted

Thoughts and prayers for all