How did New Orleans wind up in a bowl?

[RPM]

I understand that the city is lower than sea level...

but how did it get there - when were these levees built? Are the oceans higher now than before?
Is the land lower?
What gives - at some time, where they built the city had to be above sea level, right?

how how how - i just dont get it...

[myrna minx]

1. New Orleans, like Venice is sinking. New Oreans

is built upon silt at the delta of the Mississippi. on edit-add link.

http://www.cnn.com/2003/TECH/science/02/24/sinking.louisiana.ap/index.html

Louisiana is sinking
Tuesday, February 25, 2003 Posted: 8:32 AM EST (1332 GMT
NEW ORLEANS, Louisiana (AP) -- The high wooden porch slants toward the street. The twin steps are cracked. So is the plastered support between them.

"My wife and I, we'll lie in bed and notice a new crack every couple weeks," said Stalios C. Leres, who rents one side of the aging two-family house.

Southern Louisiana is sinking -- houses, cemeteries, roads and all.

While most of North America rests on bedrock, New Orleans and the surrounding area are built on Mississippi River silt. And the silt is slowly settling and compacting because of gravity.

[calico1]

2. I am curious too.

After the storm that wiped out Galveston they raised the level of the city. Did they ever think of doing this in NO? Or was it not possible for some reason? Was it ever considered? Sitting that low sure makes it vulnerable.

[SlackJawedYokel]

9. Galveston is tiny compared to NO.

They don't do it because it would change the cities historical qualities.
I mean could you imagine somehow jacking up the various historical buildings in the French Quarter 20+ feet?
Ain't gonna happen.
Easiest/quickest solution... build bigger, better levees/dikes.
But don't hold yer breath folks.
The only thing more greasy bad for you than Louisiana cooking is Louisiana politics.
We like our politics like we like our rice... dirty and bad for ya.

I'm just glad I escapted the humidity.
:D

Cletus

[calico1]

13. Actually, I was wondering why they didn't do it many years

ago, not why they don't do it now. You're right, they'd never do it now. But I had just thought of Galveston and wondered why people years ago didn't think to do the same thing there, being it is a vulnerable area.

[Bridget Burke]

11. Galveston was "raised" AFTER the 1900 Storm.

The Seawall was built & everything behind it was raised--up to 11 feet. Buildings were jacked up & sand was pumped under them.

www.1900storm.com/rebuilding/index.lasso

But the greatest natural disaster in US history (counting lives lost) had to happen first. There have been bad storms since but the efforts did help. (Of course, much development has occurred beyond the area protected by the Seawall.)

[XNASA]

3. I've been doing some reading on this lately and it seems.....

That when NOLA was settled, it was mostly around the Mississippi River where the ground is about 10 ft. above sea level.

The area between Gentilly Ridge and Lake Pontchartrain was mostly swamps and bayous and was drained after the levee along the lake was built.

This resulted in NOLA being built in a giant bowl, at least the newer areas near the lake.

[demnan]

4. There might be several reasons

all due to the impact of human beings on the land. First, a lot of the delta area has been washing away in recent years so this makes the area more vulnerable to rains, second, the glaciers are melting so fast now due to global warming that the oceans are rising ever so slightly. Third, old cities with older buildings do tend to sink down as the water table beneath them changes. I have noticed this phenomonom in Alexandria, Virginia where many of the buildings predate the Civil War. The old part of town occasionally gets flooded by heavy rains and the problem seems to get worse all the time.

[candy]

5. Good port,the Mississippi and lots of cotton!

[Redstone]

6. Your tax dollars at work, of course...

in the form of the Army Corps of Engineers and their levee-making ability.

It's also why there are no Delta islands left to soak up storms coming from the south; the chanelled river drops its silt over a cliff into the Gulf, instead of building islands and marshes in the Delta, like it used to before it was "tamed" by the levees.

Redstone

[On the Road]

7. I Heard on NPR That This Was a Raging Controversy Among the First Settlers

Some thought building below sea level was insane. Others took the attitude: no problem, we'll just build some levies. The others won.

[calico1]

8. Well I think others were insane with

that idea. I have never been there but NO has so much rich history and all those historical buildings. It would be a shame for them to be lost but if it ever gets hit as hard as was feared that could happen. I saw in the news this am buildings in the French Quarter all boarded up and was just hoping nothing would happen to them.

[LeftyDarthBrodie]

10. Much like the Grand Canyon

the area now occupied by New Orleans reached it's land level thanks to Noah's flood.:sarcasm: :sarcasm:

[soothsayer]

12. Here's the history of the site

http://www.madere.com/history.html

[RPM]

14. thanks

a long, but interesting, read