Desalination, because desalination plants, also known as desalination plants, are industrial facilities intended for desalination, usually of seawater or salty lakes, to obtain drinking water.
Humans cannot drink saline water, but, saline water can be made into freshwater, for which there are many uses. The process is called "desalination", and it is being used more and more around the world to provide people with needed freshwater.