Re: Mississippi River Spring Floods of 2011
Quote:
Originally Posted by
HelmutVII
_ The designers did not have the benefit of computer modeling, CAD software and many other modern design tools that we take for granted today. The design was done by a bunch of guys wearing black pants, neck ties and white shirts with a pack of Camels in the pocket. Their tools were slide rules, and drafting was done with triangles, and parallel bars. They sharpened their pencils with sand paper. Pretty primitive but they got the job done. Also, they did not have the body of knowledge then that we have today.
They built the structure with state of the art materials for that time. Materials that are no longer used today like grade 40 Rebar and 3000 psi concrete.
The only saving grace was that if they figured 1 foot 6 inches was enough they probably made it 2 feet 0 inches. Things were heavier, thicker and wider back then. Not necessarily bad just different.
If they would build the same structure today you might see the same scheme but executed totally different. Different foundations, stronger lighter steel and rebar, higher strength concrete, wider gates.
The design is not bad, actually it's was excellent then as it is now. After all, it is almost 90 years old and has worked 24/7 since it was placed into service. _
So you're saying the ORCS is always channeling water?
Re: Mississippi River Spring Floods of 2011
Orcs keeps the 70-30 split. This article is a pretty good one.
http://www.americaswetlandresources....erControl.html
igeaux.mobi
Re: Mississippi River Spring Floods of 2011
Quote:
Originally Posted by
biged05
This has probably been asked aleady, but have they used the overbank structure? Also, wouldn't it be fair to say that now that the Atchafalaya has crested & is receding in Simmsport above the Morganza & the river is still going down in Baton Rouge that the Atchafalaya & lower Mississippi are capable of handling the flow rate & they can now start looking at closing the gates on the Morganza?
Re: Mississippi River Spring Floods of 2011
Quote:
Originally Posted by
Bandwagon King
_ Helmut, would you mind reposting the link with times & flow charts when they opened the gates on the spillway? I can't seem to find the reference you posted on. Thanks. _
I don't remember that one. Maybe somebody else did.
Re: Mississippi River Spring Floods of 2011
Quote:
Originally Posted by
Bandwagon King
_ So you're saying the ORCS is always channeling water? _
Well Yes it is actually.
Receding floodwaters reveal ruined homes, crops
Quote:
MEMPHIS, Tenn. – The Mississippi River crest has passed through the South, but the misery caused by flooding is far from over. As water recedes, residents from Tennessee to Louisiana face the task of gutting houses soaked in polluted water. Farmers will ...
Re: Mississippi River Spring Floods of 2011
Quote:
Originally Posted by
Bandwagon King
_ This has probably been asked aleady, but have they used the overbank structure? Also, wouldn't it be fair to say that now that the Atchafalaya has crested & is receding in Simmsport above the Morganza & the river is still going down in Baton Rouge that the Atchafalaya & lower Mississippi are capable of handling the flow rate & they can now start looking at closing the gates on the Morganza? _
I don't know the exact operating plan but I would suspect that they wouldn't think of closure until the total flow through all structures results in less than 1.5 million cfs at Red river landing including the normal 70/30 split at ORCS. There is an operational plan and it has been reviewed and approved. I'm sure there are people out there watching very closely for any deviation. If they deviate then there will be hell to pay.
What's the hurry to close? They have a spillway and a floodway, so why not use it? The water is behaving better than expected. Even if they close Morganza, ORCS will still be dumping large amounts of water into the Atchafalaya probably into late June or early July.
Bonnet Carre is still open and operating above design flow will probably stay open for a good while longer. At least until such time that they can safely put the pins in place.
Re: Mississippi River Spring Floods of 2011
Quote:
Originally Posted by
CajunRed
_ BigEd...for anyone out there who doesn't know or understand the full history of the three rivers and the structures that regulate them, THIS is the best piece I've ever seen. I thought I knew much of the above. Turns out that I knew way less than I thought. This should be read by all south Louisianians.
igeaux.mobi _
It was a great read. It reminded me about things I had forgotten about.
Re: Mississippi River Spring Floods of 2011
Quote:
Originally Posted by
HelmutVII
_ I don't know the exact operating plan but I would suspect that they wouldn't think of closure until the total flow through all structures results in less than 1.5 million cfs at Red river landing including the normal 70/30 split at ORCS. There is an operational plan and it has been reviewed and approved. I'm sure there are people out there watching very closely for any deviation. If they deviate then there will be hell to pay.
What's the hurry to close? They have a spillway and a floodway, so why not use it? The water is behaving better than expected. Even if they close Morganza, ORCS will still be dumping large amounts of water into the Atchafalaya probably into late June or early July.
Bonnet Carre is still open and operating above design flow will probably stay open for a good while longer. At least until such time that they can safely put the pins in place. _
You're right, there is an OP plan and if we want to change it we have to get a deveation granted, and if we don't there are enough people looking and hell would be paid!!
I'm not sure what the OP plan actually states, but it is tied in to the 1.5 mil cfs flowing past Red River landing.
Also, the overbank structure is not being used at this time. There is leakage through the needles, but it is not being operated.
