Report on 17th St Canal Levee Failure

[Pearl River]

http://wwl.com/Article.asp?id=184926&spid=

[Ixolib]

The Corps of Engineers says it never anticipated the clay would be to blame for the failure, and is now making adjustments

How could the "experts" not anticipate that the foundation (soil or clay or sand or whatever) UNDER the levees would become a critical issue in terms of strength against the pressure of water??? Duh.....

Things that make 'ya go hmmmmmmmmmm.....

[ROCK]

I had an interesting discussion with a collegue today on this very subject. We lost 12 sites in LA and plan on re-building 3 in areas where people are slowly coming back. People need money right so I agreed with him on that call even if the levees don't hold again. Makes you think just how bad the rest of the system is though. Hopefully, whats left of NO won't have to find out this year.

[terstorm1012]

Ack...I hate to think about what's under the levees that protect river towns up here in PA......this is a good report, but it scares me more. If the infrastructure was shoddy there, it could be shoddy everywhere!

[Audrey2Katrina]

I can't speak with any authority on it; and I know that liquefaction is almost always referred to as associated with earthquakes; but the principle seems quite applicable in this kind of scenario: Very moist soil with a lot of water suddenly is on the receiving end of a lot of turbulence and force (this time from surge and hurricane winds), and the result is literally a "liquification" of the soil at lower levels, and then a collapse, or slump of underlaying land--consequence something very much akin to what happened at this levee, and taking measures to prevent liquefaction in soil as saturated as that around here would, I presume, be a very expensive and meticulous process.

A2K

[MGC]

Didn't some levees break in California the other day? I'm no soil engineer but I was under the impression that any soil that is moist enough under the right conditions can liquify. I don't see how earth can hold a solid (concrete walls) when under force (water surge on walls). The design with the sheet pilings has proven to be a poor design, yet as far as I can tell the COE is rebuilding New Orleans' levees in a similar fashion. Am I missing something?.....MGC

[Audrey2Katrina]

Didn't some levees break in California the other day? I'm no soil engineer but I was under the impression that any soil that is moist enough under the right conditions can liquify. I don't see how earth can hold a solid (concrete walls) when under force (water surge on walls). The design with the sheet pilings has proven to be a poor design, yet as far as I can tell the COE is rebuilding New Orleans' levees in a similar fashion. Am I missing something?.....MGC

well they're changing that "I" design to what is called a "T" design, that allegedly provides better anchoring; but I gotta tell ya... I'm not convinced it'll hold much/any better.

A2K

[TSmith274]

For anyone interested, the following is a link to a news special on this report, coupled with an overview of what needs to be done to save New Orleans. It's very interesting... about 30 minutes long, and worth a look...

http://www.wwltv.com/sharedcontent/VideoPlayer/videoPlayer.php?vidId=54840&catId=53

[Audrey2Katrina]

Good link, thanks TS! I found 2 things of particular interest:

1.) The MRGO NEEDS TO GO!!!!!!!!
and I found it very enfuriating that even the gentleman from the Pontrchartrain Basin Foundation who would love that to happen, sighed that it just isn't... That is beyond pathetic! 2 1/2 hours of constant SURGE coming at incredible speeds up that stupid, as he put it, "Cancer in the wetlands"... caused catastrophic flooding and destruction... if nobody does anything about this monstrosity, some folks need to file a class action suit! That thing is an abomination and positively MUST GO.

2.) The efforts at rebuilding our wetlands. Unbelievable... we lost over 100 SQUARE MILES of our coastal land in 24 hours... more than 4 times our annual average--in one DAY with this storm. I was intrigued that this man once headed the group that fought against surge gates at the Rigolets, (something I've been saying for YEARS we needed) is finally conceding that while not his preference, it has now become something we really have no choice but to do if we're to protect the city.

AMEN!

A2K

[TSmith274]

Hey I'm glad you watched it. It really sums up our situation well.

And there was some interesting statistical data about Katrina discussed in the program... that Katrina's surge was traveling at 12 feet per second as it rushed into our levees.

[Audrey2Katrina]

that Katrina's surge was traveling at 12 feet per second as it rushed into our levees.

Yup... that's the "incredible speed" to which I referred in my post... just unbelievable. They'll be writing and talking about this one for a long, LONG time.

A2K

[Dionne]

The clays found in the earth in this region change volume when moisture is introduced. In my experience there is only one way to securely build on top of these clays. You must drive pilings to bedrock, form and pour concrete footers... below elevation, only then can you proceed out of the ground and build on top.

Now, just imagine how far down bedrock is in the lower Mississippi valley?

[canetracker]

The Corps of Engineers says it never anticipated the clay would be to blame for the failure, and is now making adjustments

How could the "experts" not anticipate that the foundation (soil or clay or sand or whatever) UNDER the levees would become a critical issue in terms of strength against the pressure of water??? Duh.....

Things that make 'ya go hmmmmmmmmmm.....

My thoughts exactly. I laughed when I heard that quote.

Many around here have been discussing this exact problem way before this finding came out. For the Corps to express that they did not anticipate this result is an outright lie.

[vbhoutex]

The Corps of Engineers says it never anticipated the clay would be to blame for the failure, and is now making adjustments

How could the "experts" not anticipate that the foundation (soil or clay or sand or whatever) UNDER the levees would become a critical issue in terms of strength against the pressure of water??? Duh.....

Things that make 'ya go hmmmmmmmmmm.....

I am not one normally to criticize, but how could any competent engineer(I work with engineers all day everyday)not anticipate a failure in water saturated clayey soil? Any type of protection wall has got to be anchored very deeply and preferably in a rock formation. I know those(rock formations) are not available along the Gulf Coast, so you then go much deeper to over come the overturning moment etc. that can be exerted by massive amounts of water.

Definitely makes me go hhhhhhhmmmmmmm??????????????

[Pearl River]

I'm sure the biggest reason was $$$$$$$$$$$$

[Audrey2Katrina]

I'm sure the biggest reason was $$$$$$$$$$$$

Which equates to a void of common CENTS!

A2K

[Ixolib]

I'm sure the biggest reason was $$$$$$$$$$$$

Which equates to a void of common CENTS!

A2K

Arr Arr Arr...

[MiamiensisWx]

If you really think about it, the levees are still based on 19th-century technology; in fact, much of the levee has been in place since the 1800s and early 1900s. "Maintenance" won't fix that problem.

[f5]

every one said CAT 5 levees cost to much after Katrina that seems like a wal mart discount