Most people are returning to New Orleans and surrounding areas. I wonder why the army core of engineers ?

Question

won't just build the Levey's 100 feet tall Or 2hundred feet tall?

Answer 1

First, it isn't necessary.  Many levees do need to be higher than they were when Katrina struck, but not 100 feet high.  Katrina had the highest storm surge ever recovred to hit North America at about 28 feet above sea level.

The levees also don't need to be really high everywhere. The areas at the greatest risk from storm surge are places that are directly on the coastline.  New Orleans (except for New Orleans East) is actually well back from the coast.

A practical problem restricts the realistic height one can build a levee in southeast Louisiana:  All of the area is river delta and heavy construcions sink into the soil unless properly supported.  The supports are expensive, but are still practical when building - for example - a skyscraper.  There are 350 miles of levees around New Orleans and the cost of building the system to a great height is prohibitive (even when compared with the damage done by Katrina).

The height of the levees WAS an issue for some of the system during Katrina, but the worst failures were due to improper construction rather than a lack of height.

The US Army Corps of Engineers is giving the levee system a $14 Billion upgrade, and the work will increase the height of the levees in many areas. However, accomplishing the improvments correctly is more important than exactly to what height the levees should be increased.

Finally, the wetlands that naturally protected New Orleans from storm surge have been badly erode during the pastr 60 years.  The lon-term protection for New Orleans has to include restoring the wetlands.    

Answer 2

100 feet tall?  For what reason?  It's not necessary to spend that much money on something not needed.

Answer 3

It's hard enough to build levees that are 20 feet tall because of the cost.    Even (or especially) the locals wouldn't want a levee that's 100 feet tall.

Answer 4

Why would they? it's not practical, imagine what would happen if they did that and the levees broke. I think the thing they should do is just get rid of the levees all together, they just make flooding worse anyways. Or maybe they should re-grade N.O. higher above the river/ocean.