Watermeisters Dispute Scripps Colorado River Study: Are Their Heads in the Sand or the Clouds?

Here's my special Happy Valentine's Day - Good News post. Smile, things could be worse.

The Scripps report that was the subject of one of yesterday's posts is already generating blowback from water officials. Should we be surprised?

The story in the New York Times on the Scripps report also included some comments from various water officials. Below is Gig Conaughton's story from the 13 February 2008 North County Times (San Diego and Riverside Counties). Brown and Caldwell's California Water News alerted me to this article.

Lake Powell and Lake Mead, the massive Colorado River reservoirs that help keep Southern California wet, could run dry by 2021, according to a report released Tuesday by two Scripps Institute of Oceanography researchers.

Their dire predictions were immediately challenged by federal and local water officials.

Researchers Tim Barnett and David Pierce said there was a 50-50 chance that the reservoirs will be dry by 2021 --- but that they were not predicting that would actually happen.

Instead, Barnett said, the report predicted only that the chance the lakes will run dry by 2021 could be reduced to a coin flip -- one chance in two -- because people were using too much of the Colorado River's water and global warming was eating away the southwest United State's "normal" precipitation.

Officials from the federal Bureau of Reclamation that manages the Colorado River and its reservoirs immediately challenged the report.

The agency's regional director, Terrence Fulp [Note: Fulp is area manager of the Bureau of Reclamation's Boulder Canyon Operations Office], said the agency's own studies predicted that Mead and Powell would be a little less than half full in 2021 -- levels that would provide enough water to supply California, Nevada and Arizona for two years even if the river stopped flowing.

Meanwhile, water officials in Los Angeles and San Diego County said the public should not panic over the Scripps report. They said agencies were already working to cut water use.

They also said the Colorado River was poised to end its current eight-year drought.

"Right now we're sitting on the best snowpack in 11 years -- 128 percent of normal," said Roger Patterson, assistant manager of the Metropolitan Water District, Southern California's main water supplier and the agency that built the Colorado River aqueduct.

However, Barnett, a geophysicist, said the Scripps study looked past today's conditions and into the long-term reliability of the Colorado River, which has been the key water supply of the populations and economies of Southern California, Nevada and Arizona.

Barnett said federal statistics show that California and other states are currently taking 1 million acre-feet of water a year more out of the Colorado River than the river's flows provide.

That, he said, eats into Mead and Powell's storage. An acre-foot is enough water to sustain two households for a single year. Barnett said there was 13 million acre-feet of water in Powell and Mead as of July 2007, and that if people continued to overuse the river by 1 million acre feet a year, the reservoirs would be empty in 13 years -- 2021.

Barnett said that if Mead and Powell ran dry, it would cut hydroelectric production important to the entire West, and make the Colorado River's supplies "highly unstable" because they would be based on year-to-year flows, not stored supplies. Barnett said the Scripps report relied on a Princeton study, which relied in turn on more than a dozen climate studies that showed global warming would decrease rain and snowfall runoff in the Southwest by 10 percent to 30 percent in the next half-century. He said that even if people cut their water use, global warming-caused reductions of runoff would eventually make the river an unstable supply.

"You have to wonder if the civilization we've built in the desert Southwest is sustainable in the future," Barnett said.

Patterson, however, said the Scripps study was based on the idea of a continual decline and did not consider that the Colorado River's flows would rebound, despite global warming.

He said the current snowpack could mean that there would be 3.5 million more acre-feet in the river -- even after California and other states take their allocations in 2008 -- more than reversing the 1 million acre-foot a year deficit in the Scripps study.

"If we have back-to-back years like that, we're back in a surplus condition," Patterson said, meaning that Powell and Mead would be largely restocked.

Patterson and Ken Weinberg, the water resources manager of the San Diego County Water Authority, said that water agencies were taking steps to cut water use.

"No one is planning to continue to use the river the same way they have been historically," Weinberg said.

He said an illustration of that effort came in December, when California, Arizona and Nevada agreed to a drought allocation plan that would call for states to voluntarily take less water from the river if levels in Mead and Powell got too low. The plan was the first such emergency-rationing strategy in the river's history.

"We didn't expect such a big problem basically right on our front doorstep. We thought there'd be more time." -- Tim P. Barnett

Comments

[Michael]

Thanks for the correction, Dave.

[DW]

Terry Fulp is the area manager of the Boulder Canyon Operations Office. Lorrie Gray is the regional manager.
BTW, Dr. Fulp is a straight shooter in my opinion