In the United States, thermoelectric power generation — mainly coal, nuclear and natural gas — accounted for 41 percent of U.S. freshwater withdrawals in 2005, U.S. Geological Society data show.

Drinking less beer and more water is usually a good diet plan -- unless you're the world's largest beer brewer. Instead, Anheuser-Busch InBev is planning to make more beer while reducing water use. Every liter it produced in 2007 required about five times as much water to produce it.

Water flushed down the toilet soon could be used to operate power plants in Charles County, MD. Under the plan, the county's sewage would be pumped to treatment stations and then routed to area power plants. Instead of groundwater, the plants would use the treated sewage, called effluent, for their cooling towers and other operations.