Here's an absoultely astounding article (Hat tip to Steve Walsh) about what "might" happen to New Orleans if a large hurricane hit it. The article was written in October of 2001:

The boxes are stacked eight feet high and line the walls of the large, windowless room. Inside them are new body bags, 10,000 in all. If a big, slow-moving hurricane crossed the Gulf of Mexico on the right track, it would drive a sea surge that would drown New Orleans under 20 feet of water. "As the water recedes," says Walter Maestri, a local emergency management director, "we expect to find a lot of dead bodies."

Chilling...