Rich nations can conserve water

Efforts to conserve water - from low-flush toilets to more efficient power plants and crop irrigation - are working so well that Americans use less of it than they did 30 years ago, a report issued Thursday by the federal government says.

The flat trend in consumption came even as the USA's population grew and electricity production, the largest user of water, increased.

The study from the U.S. Geological Survey says consumption is largely unchanged since 1985 and is 25% less than the 1970s, when it peaked.

Here is some more evidence:

The biggest savings have been by industry. And that is a 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 recirculating it in a closed loop.

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

Here is the full story, which also ranks states by water use. Here is the original report. On a global scale, agriculture accounts for 70 percent of water use, which indicates further room for conservation. It is indeed a problem that rich nations use ten time more water per capita than poor ones. But in a time when people are talking seriously of nanotechnology, can cheap desalinization be so far on the horizon? Read here on a recent Israeli effort.