Between now and 2020, the greatest increases in population growth in the United States are projected to happen in the places that have the biggest problems with fresh water availability. This isn’t just a drinking water problem, or even an agriculture problem. It’s an energy issue, too. Most of our electricity is made by finding various ways to boil water, producing steam that turns a turbine in an electric generator. In 2000, we used as much fresh water to produce electricity as we used for irrigation—each sector represented 39% of our total water use. (From a poster at Lawrence Berkeley National Laboratory.)