I'm not even sure that will help as the entire area is sinking.
The building codes need to be such that no home can be build unless the habitable spaces are 15-20 feet above sea level. And those codes need to be strictly enforced.
Unfortunaly, that means most people can't afford to build a home in such a place.
Its a very bad/sad situation that is only going to get worse.
New Orleans will survive, but we all are going to have to pitch in to help.