is it true that the river will wash away sediment when it....

Intuitively, I wouldn't think it would recede fast enough for that to be an issue. But IDK!

And most of this board doesn't either.

I dont see how water would was away more sediment as it falls. I would also think that as if falls and the water pressure on the levees fall we would be in better shape.

I also don't understand the "need" to worry. As if that would help.

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so for the month or so that the water has been covering the levee that dirt is getting very saturated. So when the water begins to recede the force of the receding water could break off small parts of the levee

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Pretty close. Two things happen. The weight of saturated soil is a lot heavier than dry soil. If the river recedes too quickly the soil will slide because there is no more pressure from the river to hold it in place. The corps will use the same things it did to drop the water levels in reverse to keep the levels high and try and force a slow decrease in water levels. The other thing is as the river rose with those high volumes it may have scoured the bottom of the levee and again when pressure is removed the soil could slide off the side.

the way the corps is talking the river will drop very slowly so I would think the chances are small but not impossible

You think the pressure exerted by the river will make the level stronger? Is that what you are saying?

god help us, you, if that is what you are saying.

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Every wave (surge) that comes in gradually pulls the bottom layers of the castles wall out.

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Pretty shitty analogy

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When will we hear about all that sediment being washed into the Gulf and helping add land that has been lost to coastal erosion?

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Thats how the Atchafalya Basin was formed.....after the Morganza was opened in '73

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This is the same principal as how a plane flies.

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free thinkers.

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It was actually kind of close to right. In addition to saturation and scouring, if the water levels drop too fast and the speed of the water decreases quickly the pressure onthe levees from the river will increase quickly also. As velocity of a fluid increases, pressure decreases and vice versa. It seems like the most dangerous scenario would be a quick decrease in the water level followed by another increase in the level.