A bit of other bad news you might want to consider. While the levees are designed to keep water out, they also act to keep water in when they are breeched and remain intact. Big problem that hasn't been addressed from an enginneering standpoint. The surge can not recede, the pumps are not designed to work 30 feet under water and the debris and various lifeforms and casualties are all trapped in the bowl. What a nightmare.
Well they can punch some holes into the levees down after the storm passes. That will allow some islands to form in the bowl, if any of the bowl is above sea level. That might help to pick up anybody who remains alive.
lets hope FEMA has some huge "portable" pumps.
It's obvious to me, at least, that the only plan the bozos in charge of emergency prepardness ever had down in southeast Louisiana was to hope their luck held out and the things kept turning. I believe they were still thinking like this yesterday during the presser.