I think sometimes it’s better to replace rather than to try to repair something with many faults. It might seem less expensive to repair but it just forestalls the expense, which will be paid, and carries with it the risk of incurring additional expenses tied to failure.
I said some time ago on this thread that the Main Spillway gate structure needs to be replaced. That statement is based upon items from this thread, talking with others in the water business and my personal observation(s) None of which will have any impact on the outcome. We did however relocate some small assets and one family member out of the downstream area last month - permanently.