New Orleans: Breach closed in 17th Street Canal levee

Times Picayune ^ | Sept. 4, 2005 7:32 p.m. | joe darby

[jonatron]

The breach in the 17th Street Canal levee that had put the city of New Orleans underwater was essentially closed early Sunday evening after days of work and the use of "ingenuity to the max," a top U.S. Corps of Engineers general said.

[_Jim]

Imagine, for example, that Osama bin Laden had had a plan to blow a hole in one of these levees, and flood New Orleans.

Once again, nothing can really compare to the AWESOME power of mother nature; 200 linear feet of breech does not/will not compare to a 'hole' attempted to be blown by some terrorist when the lake level is nominal (low IOW) ...

To accomplish this 'task' mother nature caused water to:

"overtop a floodwall and scour out the foundation, leading to a structural failure of the wall"

The top of the concrete floodwall, which sits atop an earthen levee, was 14-15 ft above sea level at the point of failure. (The city is 6 to 10 ft below sea level at that point.)

Let's see a terrorist do all that ...

http://archrecord.construction.com/news/daily/archives/050830neworleans.asp

[_Jim]

Update on the status (as of a couple of days ago) on the pumps according to an article in an industry trade journal:

The Sewerage and Water Board is inspecting its pump stations, preparing to bring the flooded ones back online as soon as possible, Naomi says.

"Some are already working, but they're in areas that are not affected right now," he added.

A power station on Claiborne Ave., near the Jefferson Parish line, is critical to the effort, engineers said. The station, which was flooded and knocked offline, supplies 60% of the power to S&WB pumping stations.

"It's a specially designed system, dedicated to the pumping system. It runs on 25 cycles. It's old, but the Corps and the Sewerage and Water Board just spent a lot of money making sure it's in good running order."

The station, and a high-capacity pump station, took on water, but are on relatively high ground, he said. Crews will place about 1,000 bags of cement around the station's perimeter and pump it dry before restarting the power, Naomi said. He was not sure how soon that will be, however.

http://archrecord.construction.com/news/daily/archives/050830neworleans.asp

[Mad_Tom_Rackham]

I would think the Army Corp of Engineers is already doing, preparing or otherwise planning full inspection.

And, not to state the obvious, but they will certainly be planning the upgrade of the entire levee system (which has benn, shall we say, underfunded to date). Budget will be found now. The city and state will have to forego some casinos and sports areanas for a few decades. They might even have to trim welfare payments. The horror!

[Vis Numar]

Lets hope for a third party uprising soon, that's our only hope out of the mess.

[buckandbuck1]

Military rolls in - things get done. Bravo boys!

[nicmarlo]

From now on, whenever a task is performed with maximum bumbling and incompetence, we can refer to it as "pulling a Nagin." ;)

I thought it fit quite well, lol! : )

[Nov3]

I'll admit I'm nowhere near as polished as you apparently are, in avocations involving a lot of sucking.

Your mom and sister taught me everything I know.

[proud American in Canada]

I thought it fit quite well, lol! : )

LOL! It certainly did. ;)

[George Oh Well]

"Your mom and sister taught me everything I know."

You're very well aware that my mom and sister are dead. They laughed themselves to death the minute you pulled your pants down.

[Nov3]

You're very well aware that my mom and sister are dead. They laughed themselves to death the minute you pulled your pants down.

After two girls have worked the events they have well - you got to expect that. . . .

[hobie-one]

just curious, now that the water is leaving the city, just where is it going? Of course it will end up in the gulf and considering the vivid descriptions we have been given as to its contents, just what kind of impact will that have in the gulf? Sort of reminds me of the flooding after hurricane floyd here in eastern NC and the pigs floating down the river.....which ends up in the Atlantic Ocean.

[IrishCatholic]

This is my understanding. The levees held. It was the flood control walls that failed. All of the mainstream press has missed this even though a spokesman from NO emergency management was trying to make the point during their special on Sunday night.

[Frustration]

I heard one idiot on MSNBC say it may be the year 2100 before New Orleans is inhabitable !

ROFL!

People didn't know about the flooding till they woke up Tuesday morning... By Thursday, National Guard troops were streaming into the city in force. By the following Monday (today) the levee is fixed. Bush has done a heck of a job considering how badly the governor and mayor screwed things up before he took charge.

[_Jim]

just curious, now that the water is leaving the city, just where is it going?

'Excess rainwater' is normally pumped straight into lake Pontchartrain; under normal circumstances, they pump the first rain waters into a bayou to the south and east of the city thereby bypassing the pumping of 'debris' into Lake Pontchartrain ...

There is no provision to pump into the Mississippi River; this would necessitate going up hill quite a bit further ...

[_Jim]

It was the flood control walls that failed.

Did you see the second paragraph in post #179?

Looks to me like it was an unfortunate 'cause and effect' relationship that caused the failure ultimately; with water as high was it was, pouring over the wall, it was just a matter of time before the weakest point(s) in the system succumbed to the scouring effect. There are probably a number of other points where this was going on, and these areas will have to be back-filled to return the levee flood walls to full flood-holding strength.

[_Jim]

A bit of the history of the area around the river and New Orleans:

The blue lines represent the drainage canals in New Orleans; notice they exist only close to Lake Pontchartrain.

The Mississippi River deposits more silt closer to its banks during the spring floods. For that reason, the land is higher closer to the river. As one moves away from the river's edge, the land sinks to about 5 to 10 feet below sea level, maybe higher in some places. Because the river deposits more silt closer to its banks, the riverbed itself has been built up so much that the river's surface is actually higher than the surrounding land. Only the natural levee along its banks is higher than the river's surface, and the river is naturally prone to overflow this levee and inundate the low land around it. Because of this, the U.S. Army Corps of Engineers has extended the height of this natural levee in an attempt to keep the river within its natural course.

All of the high land along the river's bank had long since been claimed and developed, but more was needed. In order to reclaim the swamp, a series of canals and pumping stations were built. The pumping stations were able to drain hundreds of square miles of swampland, pumping the excess water into Lake Pontchartrain to the north of the city and into the swamps and bayous to the south, thus leaving behind a dry, yet still spongy prairie upon which the city could sprawl. As can be seen in the photo-map above, the system of canals drains the land farthest away from the River. These are the lowest areas within the city, lying below sea level and naturally covered by shallow marshes and swamps. No canals are needed to drain the land close to the river's banks since the river has built up this land to an elevation a few feet or more above sea level. As water must flow down, the canals drain into the Lake and bayous surrounding the city instead of into the River itself, as one might expect.

The few [only 2 or three seen here] canals that *do* empty into the River are connected to it in order to allow barge traffic to pass through them.

[The Brush]

If I were to someday end up with two women for an evening, would I connect them in series or parallel?
Some folks may laugh, but I think you've asked a series question.

LOL

[hocndoc]

There's y'alls' problem: you're supposed to connect to the women, not connect the women to each other.

[The Brush]

There's y'alls' problem: you're supposed to connect to the women, not connect the women to each other.

This explains why I failed electric shop.. and why I was kicked out of Boy Scouts (for crossing the wrong women)

[Victor]

"....But after several days, the clay foundations on the town side of the levee have been soaked thoroughly. It is possible parts of the levee will brust open as water is trying to be pumped out of New Orleans......"

I wonder if ultimately the whole levee can be encased in concrete? Seems to me that forms could be built and then pump it full of concrete.

But what do I know....