Vietnam Era "LZ Cutters" were 10,000 pound High Explosive bombs dropped by C-130's or CH-54 Sky Crane Helicopters. They were fairly effective at making an instant LZ in the Jungle....and simultaneously supressing any hostile fire from the newly created wood line! The current version is a 15,000 pound device nick named "Moab".
As water is incompressible....and the sea has far more resistance than air....what good would it do?
If my Eighth grade physics class holds....everything in life seeks the path of least resistance.