I did hear on the tv that the levees were made to protect against Cat 3 hurricanes not Cat #5's
According to officials from Plaquemines Parish, the levees have never been tested against a Cat 3, so they're not counting on them even for that intensity.
New Orleans can't survive a Cat 4 storm, much less a Cat 5. The folks who spent a lot of time and money boarding up the windows on the first and second floors of buildings were engaged in a pointless effort.