re: There's too much dirt in the Mississippi River

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Fixed. For now anyway. One thing I wonder about if the river did move to the Atchafalaya is the Waterford Nuclear power Plant in St Charles parish. It relies on the Miss River for its cooling. Hope they have that contingency in their disaster plan.

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If the Mississippi rerouted its flow through the Atchafalaya basin, it wouldn't happen overnight. Likewise, the salt water intrusion would be gradual over a period of months, maybe even years.

I'd guess that short of just shutting down, Waterford could run cooling water with a higher salinity than their system was designed for safely for some period of time. In the meantime, they'd be lobbying the PSC to shakedown customers for a new desalinization plant.

no its time to divert to the basin and actually build up LA instead of letting it wash in to the gulf

Sorry I don’t know how to post links. But if you look at Wikipedia Old River Control Struture. Very informative. There is a link to a story by Jeff Masters that tells a lot. The almost failure was in the 1973 flood. I remember it. All the marsh was flooded and the sac a lait were on fire. If the river goes to the Atchafalaya it won’t be able to be brought back. I cross those structures often. You can see the grade to the Atchafalaya. The river filling up with sediment and changing course is called avulsion. Been going on since the beginning of time.

I can’t find the link but the Corps used to have a huge hopper dredge tied up at
Audubon. It had a Congressional mandate pushed through by the dredging lobby that it could only work maybe 20 per cent of the year. We paid to have it stacked to not interfere with private dredging profits.

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The old bridge in br is too low for ships to pass under. Done purposefully by Huey long. No ships go past br

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Which is why I wrote that perhaps a deep water channel could be dredged under the auspices of flood control.

The article pertained to the rising river bottom and the catastrophic effects it could cause in a mega-flood. Xu's dredging suggestion was in relation to reducing flood risk, not improving shipping.

The Corps of Engineers is too incompetent to actually fix something.

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The Corps of Engineers is too incompetent to actually fix something.

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You better hope you're wrong, because they've spent a retarded amount of money around New Orleans since Katrina.

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Just dredge it now, and dredge it on a regular basis.

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They do. The USACE dredges nonstop essentially.

I do this kind of work for a living. The cost of dredging is astronomical. Hence, why so many people are pushing for sediment diversions.

Some of the dredge spoil gets used for beneficial use. Some gets dumped offshore or in banks in the river. USACE is obligated to get rid of the spoil as cheaply as possible. So unless they get additional funding for beneficial use from other entities, it goes to the cheapest available pump out location.

The problem of coastal restoration, which is really a bad word because full restoration is nearly impossible, is extremely complex and moreso, expensive. The research in this field is relatively new, which is why you see all these studies. An understanding is very quickly being gained though, a lot of the models are damn accurate. Still, EXTREMELY dynamic system that will remain a challenge to replenish/restore/save.

USACE and the CPRA are releasing for bid a sediment diversion/relocation project coming up soon.

They are just finishing up the PCCP pump stations project in NOLA and now all the funds are supposed to go towards this 2-3Billion dollar job. It’s going to be a design build but I think they are basically going to build massive canals to divert sediment where they want.

They aren’t as incompetent as pre-Katrina. That was quite the wake up call.

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If there is too much sediment then why do some say that the Mississippi River is only delivering a fraction of the sediment load of years past.

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These aren't mutually exclusive events.

Sediment continually accumulates in the river bed, gradually raising the river bottom over time. If no dredging takes place, channels silt in and sand bars form. If the sediment buildup isn't removed (by dredging or some other means) you'll eventually have to raise the levees to accommodate the flow during high water periods.

Dams and control structures slow or stop the river flow and sediment settles out of the water column. When water is released to lower reservoir levels it doesn't have the same sediment load it would have carried if never obstructed. That doesn't mean no sediment travels downstream, just that less sediment is coming downstream. Obviously, as explained in the OP's link and illustrated by all of the ongoing dredging, plenty of sediment is still making its way downstream.

ETA: Yeah! What JimBeam said!