In technical literature i read about the problems with the locks placed in the Panama canal. These locks have a problem with a shortage of sweet water which could shorly be a problem for the functioning of the locks. Not long after that Practical Solution thought of concept of inflatable rubber bags to be placed on the bottom of the lock. Also these bags could be placed on the walls of the locks. The bags are made of glassfibre reinforced rubber. If a ship enters the lock some bags placed on the sides of the lock can be filled with air. This part of the lock now does not need to be filled with water which reduces the water use. Due to fibre orientation and air pressure these bags are form stable and will not be pressed upward by the water.
This concept is now under a wide investigation at a big Dutch engineering buro.