Earlier quoted context omitted.
The rotor wash beneath it all would be breathtaking.. and might blow all the water out of the canal. :)
Which makes me think - what about using all these choppers to blow the water in - and keep it there? :). (I assume this is an equivalent problem to the lifting problem, as the extra pressure they'd be fighting would be that of the ship displacing water.)
I do believe this is probably one of the solutions that's being investigated but I also believe it's
1. Super expensive to construct an impromptu dam under water
2. Floating a listing ship can result in more severe listing if you're not careful (See, for instance, the fact that when a ship beaches itself while the tide is out it's initially bad news - and when the tide starts to come back in it becomes significantly worse news.
Learning and humor are fun together!