The Spanish did not bother with the swamp called Louisiana when they were settling Florida & Mexico. The French came down from Canada & founded Mobile then New Oreleans. After some war or other, the Spanish held Louisiana, then it went back to the French. Napoleon sold the Louisian territor to the US. This included the whole central US, basically between the Mississippi River & the Rocky Mountians.

Almost all older houses in New Orleans were not built on slabs, but had crawl spaces underneath. From the way some houses looked skewed around in pictures, I thought some of the flooded houses in the 9th ward were built that way, but then knocked or floated off their raised foundations. I think it might be after they got the big pumps figured out, some time in the 20th cent. that they stopped building that way. I know the 50's & 60's era houses we lived in were on slabs. The Lakewood houses were of the same era & mostly on slabs as well.

I heard in one news report that it was a New Orleanean who invented the pumps that keep Holland dry. Once they were turned on, the did pump the water out much faster than anyone expected. New Orleans can get rid of water, it's levees that are a problem.

One thing I have not seen or heard much of, was the way the canals seemed to have funnelled the storm surges in a way that really stressed the levees. They must be thinking of it because I think I've heard that rebuilding them will include closable gates for times like hurricanes.

The short changing of water projects and diversion of funds to other projects in & around New Orleans has a long & dishonorable history through administrations of both parties both national & local.