While more than 70 percent of our planet is covered by water, freshwater is in limited quantities. Of all the surface water that covers the Earth, only 3 percent is freshwater. Of that 3 percent, about two-thirds of it is frozen in glaciers and polar ice caps. That means only about 0.3 percent of all of the water on the planet's surface is safe and useable for drinking, showering, watering our crops, and powering our industries. The world's supply...