re: Morganza Spillway may or may not open for a 3rd time -- lack of clear info from ACoE

The corps has taken efforts in the past to prevent salt water intrusion into the system; so I would say that there is definitely a chance it could happen without the river shifting.

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The current flood rates projected are not bad. The flow rate should be minimal (60k cfs). Water should rise about a half foot at Morgan City above whatever level you have at the time.

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Well Well well

I was called dumb saying the rise around that area would only be around 6-8”

Not by you slack, you realized that was possible

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I was called dumb saying the rise around that area would only be around 6-8”

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Half a foot over what they've already got I'd essentially a foot higher than it's ever been. Half a foot is the difference between water in or out of many homes, and that's based on projections with no more rainfall after 48 hours.

However, half a foot is not 5 feet either.

To be fair, they're likely going to put thr barge in, and that alone keeps the backwater flooding down. You also said Morganza doesn't impact Stephensville, and it clearly does.

Chalk this one up as a tie.

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The southerly winds keep the tide/water in. The added rain has no where to go but up even with the barge in place. Under normal conditions water would eventually make its way from that area to the Atchafalaya via Bayou Chene.

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The other problem is the coastal work they've done across Terrebonne parish already keeps the water levels higher than they were back in 2011. Not as many outlets for the water to get out.

It was made to open.

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There is no scenario where the water ceases to flow down through New Orleans and on to the gulf.

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Is there a reason why you believe this? What makes you think the river has always flowed next to New Orleans?

Eta: ok you dont think it has stayed static, but what makes you think it cant change course, knowing it has done exactly that for millenia?

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One good measure for the water height on this side of the basin is Bayou Boeuf in Amelia. It has been rising almost since the start of the year. I could tell by the increasing steepness of the ramp to get to the casino in Amelia.

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, not sure if this was meant to be funny, but I laughed.

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I know zero about river management and I can tell you this is 100% bullshite.

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If by “flow” he means the literal sense in that the river won’t push water all the way to the Gulf, he’s probably right because at some point between BR and NOLA the river bed becomes equal to sea level, making St. James Parish a literal gulf front coastal parish.

Then again I guess that would still mean the river would "flow" to the Gulf. Only difference then would be that it would empty into the Gulf around St. James Parish.

BUT, like you, I know zero about river management so I may be wrong.

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I know zero about river management and I can tell you this is 100% bullshite.

There is no scenario where water ceases to flow down through New Orleans and on to the gulf.

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Why are you so mad about it?

I'm only telling you what the hydrologists say. They are more qualified than you or I or anyone else on here on this subject.

Further, there is a ton of evidence that laypeople like you or I can look at to support the claim that if the river was allowed to "meander" to the atchafalaya channel that it would essentially stop flowing (or shrink to a small bayou) to BR/NOLA such as every oxbow lake in LA as well as the historic riverbeds of the Mississippi. Every 500 to 1000 years the river has switched course to a new channel ranging from Manchac/Ponchartrain in the east to just about the Texas border in the west. The current channel has been in use for the past roughly 1000 years. For the 500 years before that it was flowing down what is currently bayou Lafourche. For the 500 years prior to that it was flowing out of Manchac. For the 1000 years prior to that it was using what is now Bayou Teche. This is the nature of ALLUVIAL rivers. The create their own banks by depositing sediment and cutting off old historic channels - again, just like every oxbow lake in the delta.

This permanent course change is only likely in event of a catastrophe where the levees and controls in place fail and cannot stop the river from flowing out to the steeper, lower elevation channel of the Atchafalaya. Here is some actual elevation data from this morning to illustrate the physics that we are fighting:

MISSISSIPPI RIVER ELEVATIONS NEAR ORCS:
Knox Landing = 65' (this is the river gauge right by the control structures)
Low Sill Inlet = 64'
Red River Landing (downstream about as far as Simmsport in latitude) = 62'

ATCHAFALAYA RIVER ELEVATIONS NEAR ORCS:
ORCS outflow channel = 44'
AR at Simmsport (downstream as far as Red Red River Landing in latitude) = 40'

So the Atchafalaya elevation is at least 20' lower than the Mississippi river in this area right now. Historically it wasn't such big difference. The MS riverbed was lower and the atchafalaya riverbed was higher. The Mississippi river right now doesn't drop to less than 40 feet until it gets below Baton Rouge. The path down the atchafalaya is so much steeper there is zero doubt that the course would be preferred by the river and would be permanent.