storm order to sit in new orleans in order, how many days will the levees have to hold up before you know you're out of the woods? >> it's a trigger based system, when we operate or in this case the local authorities operate the system there's a trigger base, then we close the system and then there's also equally when it's okay to open it. when you don't open the system until it is safe to do so. >> some of the best news we can get in a bad situation which is that those levees are holding in the system is not breaking. ricky, i have a feeling it's going to be a long night, a long couple of days for you, chief of public affairs for u.s. army corps of engineers in new orleans. thanks so much for being on the program. we appreciate it. and up next, this was the scene tonight's, and a louisiana hospital. that's part of the hospitals roof being blown off. we are going to talk to a