Just double checked on it. It wasn't a video, it was part of a video... here are the details on it for now...it was east of NO, near Chalmette, under a bridge at a substation, on the Mississippi Gulf Outlet which is a man-made canal. No FR thread or other documentation. Didn't think to check the time. I was talking to my source before I saw your post. I may be able to get my hands on the pic, but it might take a while.
Some of my file notes on Katrina were posted on one of the "Bush said/Blanco said" video threads the other day--just tidbits in real time, chronologically. Picking out two pieces pertaining to what you're discussing:
~~~~
News summary of earlier events of the day, Mon afternoon 2:37PM
The National Weather Service reported that a levee broke on the Industrial Canal near the St. Bernard-Orleans parish line, and 3 to 8 feet of flooding was possible. The Industrial Canal is a 5.5-mile waterway that connects the Mississippi River to the Intracoastal Waterway.
~~~~
Tue night
The whole WWL news crew just paused and took a deep breath, 'St Bernard Parish is gone,' --heartbreaking.
A professor from LSU said on WWL yesterday that the storm surge of 22 feet inundated the 17 foot sea wall.
He said the entirety of St. Bernard Parish was under 12 feet of water within two hours.