Canals

Canals have to drain the city. Looks like they are going to be fighting against themselves.

Both sides of the equation. They are only fixing the inflow problem. What about the fact that the city needs to drain because it's below sea level and water accumulates. Are they trying to avoid flooding or just minimize it? What if it's a slow moving rain drenching storm? Then what?

How about thinking through the problem and move the damn pumps out to the lake. Then you won't have 4 manmade sea level tidal estuaries (bayous) and the miles of levees (sic) on either side (which, of course, increases the chance of failure). If you eliminate 30 miles of inland levees, you may eliminate some of the potential problems of failure. It seems to me that one pumpstation/floodgate would be less likely to fail than 30 miles of shoddily constructed levees with "floodwalls" on top of them. But what do I know? I am just a Latin teacher. Not an engineer.