There is only so much fresh water in the world of the kind people need to drink to live. Recycled water, or gray water, is water that has been used for household activities such as taking showers or washing dishes. Then there is water that is a bit more dirty such as from the toilet. There are or will be a time and a place where such water will have to be used as is or will be treated so as to reuse once again. Even now in places like Singapore and Namibia, limited supplies of freshwater are being augmented by adding highly treated waste water to their drinking water.