On the effects of water conservation, our friends at the American Water Works Association report:

The latest data from the U.S. Geological Survey (USGS) confirms what conservation professionals have known for years - water conservation saves measurable amounts of water. The USGS released its water statistics for the United States, and there was a flat trend in consumption even as the U.S.'s population grew and electricity production, the largest user of water, increased.

The data from USGS indicates that water consumption is largely unchanged since 1985 and is 25 percent less than the 1970s, when it peaked.

“It's pretty good news for the nation,” says Robert Hirsch, chief hydrologist for the Geological Survey. The agency examined 50 years of water use through 2000.

But some people knowledgeable about water use caution that some of the gains could dry up unless people change their personal habits and farmers who irrigate their crops become more efficient.

As most conservation experts realize, water that Americans saved at home has not been a result of voluntary efforts but from measures they hardly notice - low-flow bathroom fixtures and water-saving appliances - the result of the 1992 Energy Policy Act. According to the USGS, the biggest savings have been by industry, the result of water-saving technology driven by energy-saving and environmental protection laws passed in the 1970s. Utilities that once needed huge amounts of water to cool electrical generating plants in “once-through” fashion now conserve water by re-circulating it in a closed loop.

The report says the U.S. consumes 408 billion gallons a day. Homes and most businesses use 11 percent of that. Nearly half, 48 percent, goes to power plants. Watering crops takes 34 percent. The remaining 7 percent includes mining, livestock and individual domestic wells.

The USGS water-use report can be found on the agency's Web site: www.usgs.gov.