[supercat]

After the levee was breached, REPAIRS STOPPED at night. WHY?

I don't know what efforts were made to shore up the levee before the breach, but once a levee is breached, the water on both sides WILL equalize. Continued shoring efforts may help a tiny bit, but would be about as effective as trying to battle a blaze in a 1920's film vault.

[Yasotay]

but once a levee is breached, the water on both sides WILL equalize.

If the breach isn't plugged yes the water will and did equalize. This levee was on a canal coming from the lake. I am convinced that a heavy army engineer battalion could have plugged the canal and repaired the levee.