They are already sounding off even though they won't be back in session until tomorrow. They could build up a gravel pad to above sea level and build on top of that. Cost of the gravel pad: $1/2 billion. Cost of rebuilding on top of the gravel pad: $1 gazillion. A viable city at the mouth of the Mississippi and the Gulf: priceless.
Which will continue to sink.
A viable city at the mouth of the Mississippi and the Gulf: priceless.
Which Mississippi River? The one that currently flows by New Orleans? Or the one that's gonna form eventually well to the west of New Orleans, leaving the existing channel as a brackish slough?
Move it west. Deal with all three problems once.