If this guy is correct that is a huge problem. I've been assuming that many of the levees that protect the city are based on sea level assuming the Lake gets only so much higher (driven by storm surge).
If the River is allowed to backflow through the Industrial Canal then they have a real ongoing problem. Especially if the River comes up from Rita. MR GO is a relieve valve, I suppose. Time to go to the maps. My connection to the Maptech topo and chart server is down. Do you know levee heights besides the River ones?
Not sure if this graphic has heights or not. Try it and see. I have one that does but there are a lot of levees and they're all different heigths. it's too big to post too. and I don't have a direct link.
http://www.nola.com/hurricane/index.ssf?/washingaway/goingunder.html
There's another possibility too. If just one of the locks' gates are open, then it wouldn't change the wording of the article necessarily, and they would be worrying about it, but there wouldn't be a flood from that cause yet.
Not sure it matters.
The London Canal breach repair has been undermined by percolation and is leaking. Per janetjanet998 here, 6 to 8 inches of water in some neighborhoods of downtown NO.
Another report has sand boils uder downtown levees.
Not trying to be alarmist, but fixing a breach under pressure is a very difficult proposition in any weather.
No panic, no hysteria, but NO stands a good chance of flooding again.
Here is a partial list. There is a big graphic somewhere, but I haven't found the link yet.
http://www.mvn.usace.army.mil/pao/response/MAPS/LAKEVIEW.GIF
