Posted on 10/24/2005 12:28:24 PM PDT by caryatid
Decades of debate failed to answer whether a little-used shipping channel east of the city would invite disaster during a major hurricane. Katrina may have settled the argument.
After massive flooding killed hundreds in St. Bernard Parish, eastern New Orleans and the Lower 9th Ward, there is growing consensus that Katrina's surge was made far worse by the Mississippi River-Gulf Outlet, a 76-mile shortcut between the city and the Gulf of Mexico. And while the shipping industry vows to protect the channel, political momentum appears increasingly in favor of St. Bernard officials who have long warned the waterway must be closed.
Scientists from Louisiana State University's Hurricane Center say the Gulf Outlet, also known as MR-GO, and a second channel, the Intracoastal Waterway, funneled Katrina's powerful surge into a narrow bottleneck just north of Chalmette.
The funnel caused floodwaters to stack up several feet higher than elsewhere in the metro area and sharply increased the surge's speed as it rushed through the MR-GO and into the Industrial Canal. As a result, levees that would have been topped -- but not breached -- crumbled under the hydrologic assault, turning a major flood into an unprecedented disaster, according to Hassan Mashriqui, a civil engineer from LSU who had predicted the funnel effect prior to the storm.
Absent the funnel effect, Mashriqui said, "you would have had maybe 2 to 3 feet of flooding at the max, but not everybody's house underwater. It's still flooding, but one is significant and one is catastrophic."
(Excerpt) Read more at nola.com ...
Quick! Someone close that damned barn door before those horses come back!
LOL
How close does the Mississippi come to Lake Ponchartrain? Instead of being transferred at New Orleans, could goods coming down the river be transferred to ocean going vessels docked on the northern shore of the lake? Perhaps a channel and lock connecting the lake and river could be built.
Already been done. The Industrial Canal that bisected the old 9th Ward was dug in 1922. Breaches in the canal walls are blamed for much of the flooding in the Lower 9th Ward.
The lake is connected to the river and MRGO by the industrial canal and lock. It also should be filled in.
It's my understanding that the Industrial Canal enters the lake through New Orleans, which is on the south shore. What I meant is to have ships enter Lake Ponchartrain from the Gulf of Mexico northeast of New Orleans, steam west across the lake and dock at a new terminal site on the lake's north shore. There cargos may transferred to/from river barges, railroads or highways. In another words, the shipping traffic would completely bypass the Delta and downtown New Orleans.
Someone throw a snail darter in the Ninth Ward and St Bernard and let the enviornmentalists end their misery.
New theory.
Lake Ponchatrain is nowhere near deep enough to support shipping. It's wide, but it's average depth is only 10-14 feet, and there are large stretches that are only 4-5 feet deep. Since the floor of the lake is soft silty mud, dredging it would be a never ending project.
It's been looked at in the past, but it's not feasible. Besides, only a fraction of the shipping going up the Mississippi actually stops in New Orleans. You still have to keep the river open and navigable for all of the ships headed upriver to places like Baton Rouge and St. Louis.
Thanks for the ping.
This is actually a very old theory, one which in reality either did not occur or else produced a demonstrably minor effect, but one which has implications so grave that I believe the MRGO should in fact be filled in.
The only valid reason to keep the MRGO open is for large ship transit to the Michoud facility, a large Nasa assembly plant. Once the IC lock project is complete, MRGO can go. Until then the floodgate need to be just east of the Paris Road bridge. That's the only way to prevent the funnel effect.
There was no significant funnel effect during this storm. The MRGO transported surge to the IC, but did not funnel surge into the IC. This is a critical difference. This is also easily ducumented, and in fact, already has been documented. The rest of the analysis however, approximately 25%, remains yet to be completed. Actually that's not entirely true, analysis is 100% complete, the write-up is 75% finished, then after uploading for graphics and HTML work to display them, it will be posted here.
Part IV of the analysis is here:
http://www.freerepublic.com/focus/f-news/1489838/posts
If you wish to get a ping when Part V is posted, Freepmail me if you're not already on the ping list.
This is a splendid idea ... BUT, probably impossible because the average depth of Lake Pontchartrain is about 4 meters [12-14 feet].
The MR-GO has a depth of 30 feet.
It would probably be cost prohibitive to try to create a shipping lane from the Gulf of Mexico into Lake Pontchartrain. The natural limitations render it unlikely ever to be done.
I have re-read your first post to be certain that I understood what you meant. Apparently, what you are suggesting is a canal and lock somewhere in the vicinity of the Bonnet Carre Spillway [upriver from New Orleans]. Again, this would require massive construction to create a 30 foot deep shipping channel ... not only from the River to Lake Pontchartrain, but, also, through the Lake including up to some point on the north shore to create a deep water port, and then through other waterways to the Gulf of Mexico.
If you will look at a map, I think you will see what a huge undertaking this would be. I cannot even imagine how much such a project would cost and do not think it would be either economically or practically feasible.
Doesn't the government already have to perform significant dredging fairly often to keep the lanes through the Delta clear?
Towels.
Towels solve all problems.
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