Skip to comments.Pile of mud may be clue to levee failure (‘Heave' points to structural problem, not levee topping)
Posted on 10/04/2005 4:45:07 AM PDT by Maria S
A child's clubhouse, built about 25 years ago by a civil engineer for his son, provides another clue pointing to possible design or construction flaws in the structural failures that breached two canal floodwalls and inundated the city during Hurricane Katrina.
Engineer Gus Cantrell, 60, and son Daniel Cantrell, 33 &150; now a structural engineer himself &150; returned to the family's Pratt Drive house last week for the first time since Katrina struck. They discovered the old clubhouse sitting a few feet from its original location next to the London Avenue canal levee &150; on top of a pile of mud and silty sand about 8 feet high.
The Cantrells believe that extreme pressure from high water pushed soil under the base of the floodwall away from the canal and upward in an arc, something known as a heave. That appears to have raised a mound of earth into the back yard under the clubhouse. The wooden clubhouse's base is now even with the edge of the house's roof, Daniel Cantrell said.
(Excerpt) Read more at nola.com ...
Rove/Bush blew up the levee, everybody knows that. Farrakan says it's true.
Those floodwalls were remarkably light and narrow. For an earthen dam, they were thin. Such light construction demands exacting quality control. Far better to build nice wide levies that can be built to an achievable standard. If this means 300 ft. of property has to be condemned on either side of the canal, I don't have a problem with that. That is legitimate public use.
That said, the levies did what they were designed to do, and no more. If greater protection is required in the future, some land is going to have to be lost.
Rove must be a structural engineer to get that levee to do that.
Not really. There's no limit to what you can do with captured UFO technology. ;o)
Where is Calypso Louie with the offical Muslim lab report
showing traces of 'cordite' in the mud?
One of the few things that CA does right is zoning in flood plains.
I sometimes play at a golf course along a creek bed in a pretty ritzy neighborhood. The land would clearly be worth much more as housing, but would be subject to flooding, so it is not developable.
I keep wondering if there isn't some use for most of the land in the flooded areas of NO, which would not lead to a future disaster.
Put in golf courses, amusement parks ala Disney, office buildings with parking on the lower levels, apartment buildings with lower level parking, public parks with sports fields, horse race tracks, casinos with lower level parking, etc.
Sure there would be economic consequences to a flood, but not a civil disaster.
Probably won't ever happen--it would bring higher income people into the area and permanently displace low income. Nagin would lose his voting block.
Sorry, but I don't believe any of this. Th CIA convoy that regularly delivers crack and AIDS into the black neighborhoods was diverted to the levees loaded up with C-4 to make sure the destruction was complete.
Not if it displaces minorities, then it's overbearing racist government action.
Fact is that the construction firm which built this levee informed the Corp of Engineers of the substrate problem at the time of construction and requested a change order in the amount of $809,000 to correct the problem. The change order was denighed.
Well, there should certainly be no problem acquiring the necessary right-of-way now.
I wonder, when all is finally sifted out, whether it won't turn out that the levee failures were due to burrowing nutria.
Did we not also hear of "sand boils" when Rita rolled by?
Few things in this world have the desctrutive force of moving water.
You know what would be pretty slick? The reconstruction could build up the avenues parallel to the flood walls, so the first block is 10 ft above the flood line, with each subsequent block stepping down one or two feet, until you reach your base elevation. That way you would have a huge earthen dam with people living on top of it. You would have to restrict the land to surface use only, and have some controls in place to make sure nobody does anything foolish, like digging a swimming pool. But that way the land would not have to be lost.
"There's no limit to what you can do with captured UFO technology. ;o)"
Naaahhh Cheney brought it back with him through the Haliburton Stargate.
One thing I don't understand is why the canal is there in the first place. Apparently the neighborhoods where flooding began are a sufficient distance from Lake Pontchartrain. But then this safety margin is erased by having a canal go from the lake to a point where only a narrow levee protects the whole city.
Well, the Industrial Canal is there for navigational purposes. But the other canals seem to be for flood control. Water is pumped from the bottomland over the wall and it drains into the lake. Why this water could not be pumped through large concrete pipelines, I don't know.
I can prove conclusively that levees facing Lake Pontchartrain, 17 feet tall, above sea level, west of the 17th Street Canal, 13.5 and 18 feet ASL east of the 17th Street Canal, and 17.5 feet on either side of the London Canal were all topped by storm surge and wave action. The 17th Street Canal and London Canal floodwalls are 14.5 and 14 feet ASL respectively, and were almost certainly topped as well. In my opinion, this topping did not lead to significant scouring or to the levee failures at those points.
That said, examination of the post storm images of the 17th Street Canal Breach and one of the London Canal breachs show that the source of this story's claim to a heave moment (rotation of the fill under the floodwall's base) is probably also not the cause behind the breaches. It is possible that he is referring to the other London Canal breach, in which case my objection may not apply.
If my surmise as to the the sequence of the failures is correct, we will never be able to directly prove it, but the indirect support for the mechanism is extremely difficult to argue with.
For those of you that have been following the series of articles posted here, I expect part 5, "How and Why New Orleans Flooded" in the one to two week time period, and it will include an examination of those specific breaches in depth. For those of you interested but not on the original ping list, you can follow the trail starting here:
Drainage pipes would serve the initial purpose, but they would need to be of a diameter such as to equal the cross section of the canal in capacity. The canals measure roughly 14 by 50 feet, which translates to a pretty big pipe. At that point, a canal is less expensive to construct and offers a benefit/liability that pipes do not, unlimited capacity, if you are willing to overfill the canal.
This can and did cut both ways in the pre-dawn hours prior to Katrina's arrival, with certain areas pumped dry(er) while the receiving canal overfilled and lightly flooded other areas.
NO levee related story....
SOUTHPORT, Fla. -- A construction company based in the Florida Panhandle has denied allegations in a federal lawsuit that it was partly to blame for the failure of a New Orleans levee after Hurricane Katrina.
Daniel Becnel Jr., a Reserve lawyer, sued Gulf Group Inc. of Southport, a Panama City suburb, in New Orleans last week. He claims vehicles and heavy equipment the company left on the 17th Street Canal levee contributed to its failure. Gulf Group was building a bridge near the levee.
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