All that polluted water, have you ever been to south Louisiana? There's no where to pump it to, the hurrican was as huge a blow to the ecosystem as it was to the people in the south. All it can do is spread out. If we pump it out where else can it go? There's no treatment facility large enough for it, if there was one before its probably just as destroyed as the rest of the coast.
Bear in mind it won't be easy to get it to Orleans parish. Strange as it sounds, New Orleans is not in Orleans Parish, its west of it in Jefferson Parish. And I'm sure Orleans Parish is already just as flooded as the city is already. You just don't see much coverage of it cause people know where New Orleans is better than they recognize each Parish. It would just be adding more flooding to that area.
There's nothing good about the situation, its just how it is.