Fiercer water wars seen for West

Warming report predicts cost hikes

Jim Erickson, Rocky Mountain News

Thursday, February 22, 2007

Global warming likely will reduce Colorado River flows in the coming decades, increasing competition for the West's lifeblood liquid, a federal panel said Wednesday.

Reduced Colorado River flows also would contribute to more severe, frequent and longer Western droughts, the National Research Council panel concluded in a six-chapter report, Colorado River Basin Water Management: Evaluating and Adjusting to Hydroclimatic Variability.

The Colorado River Basin covers portions of seven Western states. The river has an average annual flow of 15 million acre- feet and supports tens of millions of Americans.

As the population boom continues, Western water wars will grow fiercer, water costs will rise and more agricultural water will be diverted to urban use, the report notes. Now, about 80 percent of Western water is used for crop production.

But "the availability of agricultural water is finite," and all signs point to a future "in which the potential for conflict among existing and prospective new users will prove endemic," the report says.

Water conservation and technological fixes such as new dams, cloud seeding, desalination plants and underground water storage may help buy some time, but "any gains in water supply will be eventually absorbed by the growing population," according to the report.

The National Research Council is the principal operating arm of both the National Academy of Sciences and the National Academy of Engineering.

"The point that we make is that the technological and conservation operations, although very useful and necessary, will not in the long run constitute a panacea for coping with the limited water supplies in this desert area," said panel chairman Ernest Smerdon, dean emeritus of the University of Arizona College of Engineering and Mines.

The report's projections for the West's future echo a climate- change update issued Feb. 2 by the Intergovernmental Panel on Climate Change. That panel's latest study said the U.S. West is likely to warm around 7 degrees Fahrenheit by 2100. The warming, unless accompanied by increased precipitation, would result in regional drying and reduced stream flows, it said.

The new National Research Council document calls for further study of the Colorado River Basin but offers no solutions for the West's water woes.

"The Colorado River has been called the hardest-working river, but how much more work can it be asked to do?" said study co-author Kelly Redmond, a climatologist at the Desert Research Institute in Reno, Nev.

"The issue of limitations has to be confronted eventually, and it's just a question of which generation is going to take it on," Redmond said.

"Down the road, we'll either decide that the population cannot continue to grow inexorably, or we will have to go to greater and greater lengths to find (other sources of) water and move it to where the people are."

"There's not much in here that should be a surprise to anybody," Eric Kuhn, manager of the Colorado River Water Conservation District in Glenwood Springs, said of the new study.

"The big question is, will the water management infrastructure - meaning the big state and federal agencies - adopt it or dismiss it because it's telling them things they don't want to hear?"

River of trouble

• The Colorado River has an annual average flow of about 15 million acre-feet of water. Several recent studies have concluded that the average flow will decline in coming decades because of climate warming. A look at different computer models' scenarios:

20 percent decreases were projected by the end of the century in a 2005 study.

14 percent to 18 percent declines were forecast over the next half century in 2004.

8 percent to 11 percent drops were foreseen by the end of the century in a study completed last year.

ericksonj@RockyMountainNews.com or 303-954-5129