I am a little confused. I see reports that there's going to be 5-15 feet of water into NO from the lake by tomorrow, but then the Mayor expects the city to be functioning in 4 weeks?
He meant 4 weeks on top of the 8 weeks they had planned before the latest failures. IF everything goes after plan and the water starts receding (which it won't).
If/when the pumps are working and the breaches in the levees are fixed, the pumps can expel water at a rate of 1 inch per hour (the figure is actually the rainfall rate on greater NO that it can handle). 15 feet would take somewhere around a week to pump out.