Dunno which is worse: being stuck below sea level or getting caught on the highway.
Well, downtown has some vey tall buildings, so folks could always go UP. I have a niece and nephew and their families living in Mid-City. If it starts looking really bad, they'll probably head to their grandmother's house, or my brother's house up in Hattiesburg, MS. It's about 2 hrs. north of NO, but there wouldn't be any rooms in any motels to be had all along I-59, and they might as well go where they can stay for free.