I assume that there would be a current that would erode the surrounding environment, but how bad would it really be?
I'm not sure why they can't just pump ocean water up into the canal. Perhaps it's just too much water to be feasible.
Because that would wipe out the ecosystem there, the canal is freshwater while the ocean is saltwater.
The French did change their plans to use locks after a few years of work
But more seriously interesting to see that the New Jersey Style wins again.
like digging down 25 meters has been done numerous times all over the world. But having to do that for I think like 70 to 80Km distance wise from would not be cheap.
I thought about this maybe being a usecase for small modular nuclear, another commenter suggested that that has already been done (when the US was running the show).
Several others have commented on the environmental issues with pumping seawater into the freshwater ecosystems.
The locks are like a ship elevator. If they weren't there the inland waterway would drain and there wouldn't be water to float on anymore.