A question for those familiar with the USN and probably RN engineering systems aboard ship.
On the (conventional powered or steam powered) Cruisers and Battleships of WWII there are/were water desalination plants for the production of clean water for the ship. It has many uses (cooking,cleaning,showering, firefighting etc.)
The question is what is the two most important purposes for the treated (beyond normal clean) water?
Hint its not for the purposes listed above.
