This news is particularly relevant heading into Copenhagen...for those who think conservation of any kind is impossible or unattainable or out of keeping with American goals.
The US Geological Survey released a study today showing that Americans used less water in 2005 than 35 years ago—despite a 30 percent population increase. Most of the decline is attributable to alternative cooling methods at power plants and to more efficient irrigation systems.
(The AAAS reminds us that some commercial farmers in the US have doubled the crops they grow with a given amount of irrigation water by using sub-surface drip irrigation.)
In 2005, 297 million Americans used 410 billion gallons of water per day. That's 5 percent less than in 1980, the year of peak water use, when there were 227 million Americans. Or ~1,400 gallons of water per day per American in 2005, compared with ~2,000 gallons per person per day in 1980. Not bad. And a reminder that trends can be managed, not just suffered.
The quick stats on water use in the US today:
- Nearly half of water cools thermoelectric power plants (more reason to conserve energy).
- Irrigation appropriates 31 percent (more reason to eat consciously).
- The public uses 11 percent.
- The remaining 9 percent supplies industry, livestock, aquaculture, mining, and rural household use.
We need to remember however that a changing climate requires changes in water planning. In a blog posted last year, I cited a study in Science predicting water supplies will decrease substantially in parts of North America as the globe warms (as well as in parts of Europe, the Middle East, Africa).
Wonder about your own water footprint? Read Josh Harkinson's fine MoJo piece.
Drip, drip, drip. It's all finite. Let's act accordingly.
CORRECTION: Now made in the water use per American per day. Thanks to readers.