Near the end of 21st century, the Earth faced a global water crisis. Dust bowls threatened the Great Plains, and expansion of the Sahara loomed dangerously over the Middle East and North Africa. A great search began for drinkable water, and an answer appeared from the most unlikely of sources: the Bionanotech, which allowed use of semi-biological nanostructures for the purification of water. The Aqua-Purifier came into being.