28% of rainfall turns water into steam. 57% due to short length of rivers, quickly flows into the ocean. That is to say,83% of water is gone, with only 17% left for people to use. To keep the 27% of Water, reservoirs are built,but they can only keep two thirds of the water at most. What's more, sending water to every house and company wastes another one fifth of water, because of old and bad pipes.