Washington Mud Slide

[jerrybob]

Incredible mudslide....a real tragedy for this community. Been thru that area many times.......thoughts with the families and victims.

Washington mudslide rescue operation shifts to recovery mission, official says | Fox News

 

[oosik]

Yes, I've seen videos of this on the news. The videos make this look almost like a lahar. They have given up on this being a rescue mission.

 

[dave1949]

Very sad. The news said some areas in the slide were covered to depths of over 30'.

One of the photos in the news showed the hillside where the slide originated. It looks like the next hillside to the right of that one in picture had had a landslide sometime not too long ago, maybe 30 years?

 

[PILOON]

When you stop to think about it, it is just like snow avalanches.
Different layers of different consistencies of material.
In this case water entered the equation changing the lower layer's characteristics. I'm willing to bet that there was a high percentage of clay in that subsoil. Wet clay gets slippery and the heavy top cover slides away.
Have seen similar situations in my area and generally our slides occur when excessive fill is used to level terrain with inadequate retainer walls to hold things back. Our city has just introduced bylaws to avert this type of occurrences.

 

[Western]

They said the body's have where literally torn apart from the slide and clothing was ripped off. I cant imagine what those poor folks felt.

 

[Tractor Seabee]

From Puget Sound up into the east-side foothills layers of clay are interspersed with the other layers. The clay gets saturated and creates a slip plane. This geology is well known. I would never build on a hillside in that zone. It's like folks building on a flood plane and then want the Gov to bail them out multiple times so they keep on living and get washed every two to three years. This also occurs in Seattle from time to time. Real common along the east coastline.

Ron

 

[dave1949]

Photos: Washington state landslide - CNN.com

The 11th photo clearly shows two previous slides adjacent to the this one.

The story says the last one happened in 2006 and a geologist's report said there would be more. That report didn't get translated into building restrictions somehow. That is how it is being reported, I'm sure there is more to it as usual.

 

[dragoneggs]

Yes a very tragic thing. The town of Oso is a very old and this wiped it out! I too live on a hillside on the Hood Canal. Most of my land is glacial till so the water does drain rather well. I do have a couple of clay spots and I am putting french drains or whatever you call them to help direct water appropriately as I alter the terrain to step the slope to make it more useful and manageful. Scary scary thing and my heart goes out to those fellow Washingtonians.

 

[jerrybob]

Our Search and Rescue Team just got put on stand bye......we may be up there Sat. or Sun. Apparently.....crews are getting tired and they may need some extra help. A real tragedy up there.......

 

[deerseeker001]

Its so sad to watch this on the News,how to deal with this mess.God Bless them.

 

[jerrybob]

Very tough weekend. Our S&R team worked the slide for two days. Terrible mess......mud and debris everywhere. Still can't get big equipment into many areas. Met some wonderful people.......a real community up there. We found lots of personal belongings......everything was bagged and sent for cleaning. Hopefully....it will find it's way to the owners. Tragically.....we found remains as well.....both human and animal. Our fellow searchers are some of the most respectful folks I have ever encountered. When remains were found or a helicopter flew out........everyone stopped searching......paid their respects and helped each other. Been through many rescue operations......this one was really tough. Thoughts to all the families and folks affected by this event. Thanks to all the folks up there working the recovery. We may go back next week-end.

 

[dave1949]

Good for you and team for doing that task. Can't be easy.

I saw one photo taken at street level. In the background an excavator was sitting on the road, and behind that a wall of dirt and debris that the excavator apparently was working its way into. Seen from that perspective, I could get a real understanding of how much that area was buried.

 

[bcp]

From the Oregonian newspaper last Thursday:

 

[dmccarty]

... Our fellow searchers are some of the most respectful folks I have ever encountered. When remains were found or a helicopter flew out........everyone stopped searching......paid their respects and helped each other. Been through many rescue operations......this one was really tough. Thoughts to all the families and folks affected by this event. ...

Working on a disaster site recovering property, much less remains, is very humbling... Much more so when the survivors are around.

In this case, I worry that most of the missing are buried under that mess and some might never be found.

The "landslide" looks like the hill just collapsed. We were in the NC mountains a few summers ago and some of the houses gave me the willies. They were under cliffs and if a rocks or the mountain gave way, it was going to be ugly.

Later,
Dan

 

[Dr_Zinj]

Two factors contributed to this slide. The soil type and saturation that the media have covered ad nauseum, and the fact that the river itself undercuts that hillside. Once enough material is removed, the whole thing slumps down. Rain, soil, and logging in the near past, contributed to the rest.

Point to consider for everyone building on glacial flood plain soils is that if you get an earthquake with saturated soils, the whole thing liquifies in place and can cause buildings to sink straight down.

 

[LJH]

Total respect for all participating in this recovery effort. Please be safe.

 

[dragoneggs]

jerrybob, good on you! Tough work... and noble. Be safe. I know the road as I went to summer camp several times very near by as a kid. My heart goes out to all the families affected.

 

[Larry Caldwell]

Two factors contributed to this slide. The soil type and saturation that the media have covered ad nauseum, and the fact that the river itself undercuts that hillside. Once enough material is removed, the whole thing slumps down. Rain, soil, and logging in the near past, contributed to the rest.

Point to consider for everyone building on glacial flood plain soils is that if you get an earthquake with saturated soils, the whole thing liquifies in place and can cause buildings to sink straight down.

From the photos of the area, it looks to me like there were two slides. The first was the unstable soil left over from the 2006 slide, which liquefied and wiped out the houses and highway. Then the upper bench broke loose and slid about halfway down, but did not liquefy. I have seen may slides, and the proximate cause was cutting the toe of the slope.

Risk of slide ‘unforeseen’? Warnings go back decades | Local News | The Seattle Times

 

[Tractor Seabee]

God Bless all you guys that went in there to help. I am 100 Mi away and at my age probably not much help. We are praying for the victims, their families and also all you rescue workers. Keep up the good work.

Ron

 

[turnkey4099]

Two factors contributed to this slide. The soil type and saturation that the media have covered ad nauseum, and the fact that the river itself undercuts that hillside. Once enough material is removed, the whole thing slumps down. Rain, soil, and logging in the near past, contributed to the rest.

Point to consider for everyone building on glacial flood plain soils is that if you get an earthquake with saturated soils, the whole thing liquifies in place and can cause buildings to sink straight down.

Paper today reported that there was an authorized clear cut above the slide that, per dept of Ecology report back in 1987, should not have been allowed.

Harry K