#264918 - 12/27/04 05:57 PM
Hoh River engineered log jams
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Anonymous
Unregistered
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Does anyone have any recent pics of the giant log jam project on the Hoh?
And how did the structures survive the major high water event of Dec 9-10???
Any info. appreciated.
Thank you.
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#264919 - 12/27/04 06:04 PM
Re: Hoh River engineered log jams
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The Rainman
Registered: 03/05/01
Posts: 2314
Loc: elma washington
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from what i could see while the water was still high it looked liked one of the log jams was gone
_________________________
don't push the river it flows by itself Don't argue with an idiot; people watching may not be able to tell the difference. FREE PARKER DEATH TO RATS
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#264920 - 12/27/04 09:00 PM
Re: Hoh River engineered log jams
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Returning Adult
Registered: 04/27/99
Posts: 347
Loc: Everett, WA. USA
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#264921 - 12/27/04 09:31 PM
Re: Hoh River engineered log jams
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Anonymous
Unregistered
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Looks like the river is still aimed right at the highway, doesn't it? Hopefully, as the flows drop down, we will see the gravel bars forming around the jams.
Thanks for the pics. They give a really good look.
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#264922 - 12/27/04 10:20 PM
Re: Hoh River engineered log jams
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Dazed and Confused
Registered: 03/05/99
Posts: 6367
Loc: Forks, WA & Soldotna, AK
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Looks like the jams themselves are still there, but some of the fill is gone.
You can see that the deep water a few hundred yards below is now quite shallow, perhaps from the fill material.
Nearly all the flow is still in the old channel and is right at the highway. We'll see how it does over time. The one below Morgan's is pretty much gone and it's starting to get behind the rip rap up there ... gonna be messy.
_________________________
Seen ... on a drive to Stam's house:  "You CANNOT fix stupid!"
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#264924 - 12/28/04 10:53 PM
Re: Hoh River engineered log jams
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Parr
Registered: 05/09/04
Posts: 50
Loc: Prosser WA
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Anybody know who did the engineering for those structures? I'm interested in ELJs, but am so far unconvinced of their use in high energy systems.
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#264925 - 12/28/04 11:08 PM
Re: Hoh River engineered log jams
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Returning Adult
Registered: 02/11/03
Posts: 272
Loc: Olympia
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Here's a link to Herrera Inc.'s website where you can find the newslink for the article done by the Seattle Times. Whoops! Forgot the link...here it is http://www.herrerainc.com/news.htm That last picture has me thinking that a few more high waters and the river could be eating away at 101 and eventually wash the road away. I think the 5th picture does a decent job of illustrating just how poor the fill material adjacent to the road is, looks like like unconsolidated sediment consisting of loose coarse soils and plenty of cobble. I don't understand why they couldn't have just armored the rip rap area with a wall of logs rather than making 6 small engineered logjams. Oh well, I guess we'll see how this project fares through the next couple months of rainy weather. 
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#264928 - 12/31/04 01:13 AM
Re: Hoh River engineered log jams
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Parr
Registered: 01/18/03
Posts: 56
Loc: Puget Sound, WA
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I've worked on a number of these log weir projects as well as multi-plate culvert replacement projects on a number of streams in the Puget Sound. Common sense does not prevail when it comes to engineers. They are doing a good job of placing materials in the stream that are native to rivers, such as using smooth agregate rocks instead of quarry rock. But in the case of the Hoh the previous quarry rock that was in place lasted for a long time. They should have used more in conjuction with the log ties.
In regards to the earlier post, the fill used on the Hoh project below the log ties is good material, just not good for stopping a river of this magnitude. Regardless of the material it is not going to hold up unless they use larger rock. My guess would be that they will be adding large quarry rock to bank the existing fill.
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#264929 - 12/31/04 01:47 PM
Re: Hoh River engineered log jams
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Fry
Registered: 04/04/03
Posts: 27
Loc: Bellevue
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I believe the guy's name who engineered these log jams is Tim Abbey. He works for Herrera Environmental Consultants.
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#264930 - 12/31/04 02:11 PM
Re: Hoh River engineered log jams
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Anonymous
Unregistered
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#264931 - 12/31/04 09:53 PM
Re: Hoh River engineered log jams
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Parr
Registered: 05/09/04
Posts: 50
Loc: Prosser WA
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This project should be interesting to keep an eye on. There is a faction of the engineering community that is really pushing LWD and LEJ's to resotore stream function. Another faction is convinced that the only real fix for most stream problems is BFR (big friggin rock) in inverted V weirs and barbs.
So far I have not seen a LWD do much and have seen several rock structures made of undersized material blow out. The only instream structures I have seen hold up under high flows are BFR rock structures. It would be great if ELJs could work, because agencies are more willing to permit them, and a bit more wood in some of these systems is probably not a bad thing, habitat-wise.
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#264932 - 12/31/04 11:52 PM
Re: Hoh River engineered log jams
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Returning Adult
Registered: 02/11/03
Posts: 272
Loc: Olympia
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For a river like the Hoh, logjams either natural or engineered are not static features. The Hoh is a dynamic river system that likes to move around its floodplain and unforunately for both the river and us, roads can't seem to be far away enough to avoid washouts. There is a fair amount of wood that gets moved around throughout the system with each high water event. Oftentimes it is the single logs and logjams just sitting on top of a gravel bar that get washed away. The logjams that have been around for some time are always composed of wood of all different sizes all grouped in interlocking matrices that continue to increase in size. These kinds of logjams seem to be more prevalent on the bends of the river where the force of the water keeps it pinned in place.
Anyways, I just want to comment that ELJs on the Hoh in particular don't seem to be highly successful. That is quite a bit of $$$ going into fairly ephemeral projects. I'm not too sure that this new ELJ project could really be considered a success. Just downstream of the 6 wingjams is a section of riverbank that gets shaved during every high flow. Eventually the river will come close enough to the highway that either rip rap or something else will have to be used to shore up that section. But that will take quite a few years to happen.
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