I think I just heard Nagin say a 2-block hole was penetrated in one levee.
If this is true they need to send an engineer there promptly to dream up some way to plug the breach, quickly, if at all possible. Probably dropping lots of large pieces of concrete and loose rocks initially. Waiting until the pressure equalizes means waiting until that bowl is FULL, which pushes the date of everything else way back. This actually is more important and may save more lives than the individual rescue operations. Resources should be diverted as needed. If the engineers say the breach can't be plugged then send a little Dutch boy to do the job!