I’d also mention that I think it was the COE who built some of the locks in New Orleans that failed in Katrina - which, shhh.....don’t let this get around...but Katrina was down to a cat 3 when it made landfall. That’s a very significant storm, but everything was supposed to be tight up through a Cat 3 storm.
Having said that, I know nothing about the specifics of the Panama Canal.
My daughter got her PhD at Tulane so we made more than a couple trips down there. I believe part if not most of the problem in New Orleans is that part of the French Quarter may have fallen as much as 16 feet over the last 200 years or so. We did the swamp tour and the guide pointed out that we were at essentially sea level there but still 16 feet above Canal Street.
I thought the problem in NOLA was that the dikes were over topped, (water was higher than the dikes) not that the dikes failed hydrostatically. The COE had plans to make NOLA Cat 5 proof, but could not overcome environmentalist (as opposed to environmental) objections. There was money and time enough to upgrade the dikes, what was lacking was the will.
The trouble with the N.O. gates that failed wasn’t design, it was upkeep. N.O. collected taxes/fees specifically to repair and maintain them, and then spent it on something else.
Also, N.O. is sinking a foot every 25 years, so old solutions aren’t enough.