The new White Salmon sandbar

moondog · Fri Dec 09, 11 8:29 am

Went to the WS sandbar this week and it is turning into the classic textbook example of the "friction dominated delta", that kitezilla depicted on his master thesis of sandbars. A Bar is forming on each side of the bank and in the middle. Their are 2 main channels flowing between the 3 bars. Talked to a fisherman and he said they would walk out on the sandbar and cast for salmon from the edge of the bar. Do I foresee a little tension out there next summer?

kitezilla · Since 22 Jun 2006 453 Posts gorge Obsessed

We have another 'kite beach' where a "River Runs Through It" and I don't see fishermen casting from HR's 'The Sandbar'. Really, we have two, if you count the unmentionable one that rhymes with 'tit-for-tat'.

It could be that the fishing won't be any good from shore, anymore, now that the deep channel is history.

moondog · Sat Dec 24, 11 11:41 am

The first launch Nov, 2011

moondog · Wed Mar 07, 12 5:56 pm **march 7, 2012 update photo**

After the heavy winter rain and snow season I was disappointed not to see a more pronounced sandbar. It has grown in size but not much is above water. The water level was low today. The HR sandbar was out in it's full glory. Most of the WS bar was 2-6 inches below water, but huge! The waves were very small just upwind of the bar. To the south of it we had the typical 2-3 foot swell. Somehow we need the mass of sand at the Native American in lieu site to build up the existing base.

hilton · Since 15 Aug 2008 787 Posts Opinionated

I walked around a bit on the new sand bar Sunday.
Much like the HR bar, the outside edge is soft and drops off fast.
The middle, however, felt quite solid although it was (as you said) under water between calf and thigh deep.
The water upwind of the new sandbar was (sadly) pretty flat.
Much flatter than the waves/swell out in the main channel.

genek · Since 21 Jul 2006 2165 Posts East Po KGB

dangler · Since 26 Feb 2006 1744 Posts WINDY SPOTS XTreme Poster

It would be nice to avoid the bridge toll from carson

apctjb · Since 19 Aug 2007 427 Posts Obsessed

Anyone know if there are plans to dredge a channel to the Indian boat ramp?

That could add some extra spoils to the bar...

apctjb · Since 19 Aug 2007 427 Posts Obsessed

Sand bar as of today; if you look in the middle you can see someone out trying out the new "pool"

kitezilla · Since 22 Jun 2006 453 Posts gorge Obsessed

Wanted: "Sleuths" and "Observers"

This should be an interesting 5 month period, concerning 2 related 'natural' phenomenum...swell on the river, and sand bar transformation.

If you look at the old picture of the WS delta, taken from the Eirie, you may find a few hints of what is to come. My guess is that the picture was taken on a day in August, based on the fact that the river is low (judged from the distance the water is from the shrubs on the shore). I would guess August because of the windless appearance of the river, the leaves on the Oak tree, and the high position of the sun. My guess is that the sand bar will look like that in the picture, this August.

Can you find any other things in the picture, that would be fun, on which to base a hypothesis?

As far as "swell" (technically, or more accurately, 'chop') goes... the subject gets very interesting... where will it be best, when, and under what flow conditions of the Columbia and WS rivers?

In guessing at the "swell", here are two basic facts to be considered:

(1) Ocean or lake waves: The waves move, but the individual molecules of the water stay in one place (going in little circles).

(2) River or Ocean current waves: The waves stay in one place, but the individual molecules of the water move (all the way from its source to its destination) .

A third fact to be considered where water is driven by 'current', is that: When fast water meets slow water, a hump, (standing wave, like you see on a river) will occur.

A forth thing that will cause a hump or water to form, is where a wave 'feels' the bottom, as it encounters a shallow area.

When you put together these 4 phenomenon, you may be able to form a hypothesis, explaining the 'what, where and when' of swell formation on the Columbia River.

Put on your thinking caps and clean your sun glasses...

mazzi · Since 28 Jul 2008 6 Posts Portland, OR Kook

It will be interesting to see what happens to the bar over the next several seasons. I have a personal and professional interest in river dynamics and it has been fun to read everybody’s different hypothesis. The physical processes involved in the evolution of the sandbar are extremely complex and not fully understood by science (at every scale). There are advanced morphological models that can account for the first order processes but it’s difficult to accurately define all the inputs, account for natural variability (i.e. sediment supply), and collect data to calibrate and validate such a model. Bottom line…anybody who tells you that they KNOW what’s going to happen to the sand bar is a fool. The best indicator as to what’s going to happen is to look at other tributaries, as some folks have pointed out.

The more relevant question for kiter’s (as kitezilla has pointed out) is: what impact will the new sandbar have on the water conditions, mainly swell.

Kitezilla - I like your attempt to identify the first order controlling processes but, no offense, they aren’t relevant (nor are they all accurate). You’re missing the driving force, WIND. If swell were only controlled by bathymetry (the river bottom) and current speed, the waves would be there with, or without, wind which they are not. WIND is the primary driving force.

Then question becomes: why are the waves bigger in certain areas (i.e. pre-dam breach White Salmon, Arlington, Doug’s Beach, Hatch, etc.)? What do all those areas have in common? Higher current speed (velocity) – that’s the second requirement for big swell. Each of the sites have higher velocities for different reasons; most are from a slight channel constriction, and you can see that in Google Earth. The Hatch is a natural bedrock outcrop that causes localized flow acceleration, Doug’s in the same, the areas just east of wind mt. is another natural constriction which has massive swell. Arlignton’s big swell is caused by the manmade marina which creates localized swell just downstream near the OR side – you all know where it is. The story at White Salmon is less obvious and can’t be seen from Google Earth. The flow acceleration there was being caused by the old underwater delta which was there before the dam came out, as somebody pointed out. River currents would accelerate over the top of that underwater delta creating higher velocities, more wind drag, and thus bigger swell. So the question about what will happen to the swell with the new sandbar depends on what the new river bathymetry looks like and what affect that will have on local velocities. It seems like the sediment wedge is now causing flow to go around, rather than over, the delta which will still create flow acceleration and swell conditions. From early observations (kiting) there is still swell downstream of the mouth but the waves seem more unsettled (but I’ve only been out twice this year). I wonder if that’s related to there being more turbulence. The flow transition is more dramatic than it used to be and maybe that’s creating a lot more turbulence. In any event, expect the sandbar geometry and swell characteristics continue to change as the river slowly adjusts to its new dynamic equilibrium. It will probably take several seasons for the changes to slow down, depending on how well they control the remaining upstream sediment.

Sorry for all the nerd talk, somebody else started it…

mazzi · Since 28 Jul 2008 6 Posts Portland, OR Kook

It will be interesting to see what happens to the bar over the next several seasons. I have a personal and professional interest in river dynamics and it has been fun to read everybody’s different hypothesis. The physical processes involved in the evolution of the sandbar are extremely complex and not fully understood by science (at every scale). There are advanced morphological models that can account for the first order processes but it’s difficult to accurately define all the inputs, account for natural variability (i.e. sediment supply), and collect data to calibrate and validate such a model. Bottom line…anybody who tells you that they KNOW what’s going to happen to the sand bar is a fool. The best indicator as to what’s going to happen is to look at other tributaries, as some folks have pointed out.

The more relevant question for kiter’s (as kitezilla has pointed out) is: what impact will the new sandbar have on the water conditions, mainly swell.

Kitezilla - I like your attempt to identify the first order controlling processes but, no offense, they aren’t relevant (nor are they all accurate). You’re missing the driving force, WIND. If swell were only controlled by bathymetry (the river bottom) and current speed, the waves would be there with, or without, wind which they are not. WIND is the primary driving force.

Then question becomes: why are the waves bigger in certain areas (i.e. pre-dam breach White Salmon, Arlington, Doug’s Beach, Hatch, etc.)? What do all those areas have in common? Higher current speed (velocity) – that’s the second requirement for big swell. Each of the sites have higher velocities for different reasons; most are from a slight channel constriction, and you can see that in Google Earth. The Hatch is a natural bedrock outcrop that causes localized flow acceleration, Doug’s in the same, the areas just east of wind mt. is another natural constriction which has massive swell. Arlignton’s big swell is caused by the manmade marina which creates localized swell just downstream near the OR side – you all know where it is. The story at White Salmon is less obvious and can’t be seen from Google Earth. The flow acceleration there was being caused by the old underwater delta which was there before the dam came out, as somebody pointed out. River currents would accelerate over the top of that underwater delta creating higher velocities, more wind drag, and thus bigger swell. So the question about what will happen to the swell with the new sandbar depends on what the new river bathymetry looks like and what affect that will have on local velocities. It seems like the sediment wedge is now causing flow to go around, rather than over, the delta which will still create flow acceleration and swell conditions. From early observations (kiting) there is still swell downstream of the mouth but the waves seem more unsettled (but I’ve only been out twice this year). I wonder if that’s related to there being more turbulence. The flow transition is more dramatic than it used to be and maybe that’s creating a lot more turbulence. In any event, expect the sandbar geometry and swell characteristics continue to change as the river slowly adjusts to its new dynamic equilibrium. It will probably take several seasons for the changes to slow down, depending on how well they control the remaining upstream sediment.

Sorry for all the nerd talk, somebody else started it…

blireef · Since 31 Aug 2009 37 Posts

I'm looking at all the cams available and am not seeing the sandbar, does anyone have a current image of it, is it still above water?? Big Jim Question

moondog · Fri May 18, 12 8:05 am **where am it?**

When the HR sandbar has a small crescent showing, the WS bar is under water. I went out tuesday and it was completely submerged with just a couple of ankle breaking logs visible, one upstream and one downstream. I went within 50 yards of the bridge where I knew it was shallow and slowly dismounted from my board and started sinking up to my knees. It will take a full season for everything to stabilize. When the HR bar is in it's full glory the WS bar has about 200 square yds. of useable space with lots of debris to catch kites and lines. The wave dynamics are totally different this year with pros and cons depending on your kiting preferences.

Ryan · Since 14 Jul 2005 536 Posts Oregon Addicted

Mazzi, I agree with you. Lets not forget fetch. All those locations have a long strait upwind river section to build waves. Also, to much velocity is not good either, ie Rufus most of last summer.

I just hope we launch and land from the WS SB and the head upwind to the waves.

kitezilla · Since 22 Jun 2006 453 Posts gorge Obsessed

Here are 3 other factors that I think will become important in the discussion of the "what, where and when" of these 'humps' of water, on which, we love to play.

(1) The density of water being over 700 times that of air. The relevance of this will be more obvious, if you consider the force and inertia, exerted by wind (moving air) of 10 MPH compared to the force and inertia of a stream of water, moving 10MPH.

(2) "Wave Trains" ... those formed on a river, by moving water, as a result of a 'drop and pool' feature... compared to the wave trains formed on a lake or ocean, as a result of the pressure of moving air. The waves formed in a classical wave train resulting from a 'drop' in the river, stay in pretty much the exact same spots... whereas the individual waves in a 'set' of waves, resulting from wind, will rotate, where the leader wave will disappear, and reform at the tailend of the wave train. The Columbia River combines both of these wave train phenomenon to create the humps of water that we so love.

(3) The casual use of the words "wave" and "swell" as opposed to the technically accurate use of the words, along with the word "chop". People who live or surf on the ocean have always been annoyed at the misuse of these words, by Gorge people, and I have to agree with them... but I also have to agree with them, when they admit that whatever you call the 'humps of water', that are found in the Columbia River Gorge...that those humps are a lot of fun.

We have all noticed that "too much" current and "too little" river current, wreck the "swell", by either shortening up the 'wave period' too much... or flatening out the height of the 'wave'. The above listed factors (1) and (2) may be helpful in figuring out the "why" of this observation.

Wheeew! Deep stuff!

For the "Geek-challenged" Dudes, who, about now, would like to give me and my "Dude-challenged" Bros, participating in this discussion... a virtual Atomic Wedgie, here is what we are talking about:

" If you feel like your teeth are gonna break, it's chop. If you feel like your back is gonna break, it's a swell." Very Happy

Sella · Fri May 18, 12 12:38 pm