Healthy snowpack bodes well for Arizona

Tony Davis in the Arizona Star: The northern Rockies have been slammed with enough snow this year that it might be possible to delay shortages of Colorado River water for Arizona water users for two to five years, officials say. After years of drought and below-normal snowpack in the Colorado's Upper Basin, primarily in Utah, Colorado and Wyoming, this year's snowpack there is now about 120 percent of normal, said a U.S. government forecasting agency.

The Colorado River Basin Forecasting Center predicts that April-July runoff into Lake Powell, which straddles the Arizona-Utah border, will be about 113 percent of normal. That's about 9 million acre-feet of water. An acre-foot is about 325,850 gallons.

Last year's April-June runoff was only 73 percent of average, or 5.79 million acre-feet, said Brenda Alcorn, a forecaster for the center in Salt Lake City. For the decade of 2000-2009, the Colorado's average annual flow into Lee's Ferry, just below Lake Powell, was the lowest for any decade since authorities started keeping records on the river more than a century ago.

Last year's low snowpack and runoff sent Lake Mead at the Arizona-Nevada border to its lowest level since 1937, about 1,082 feet above sea level. That prompted predictions that the Central Arizona Project might start seeing shortages affecting farmers, mines and other users of excess CAP water as early as 2012. Excess CAP is water that a local government, tribe or other user has a contract for but isn't buying or using.

But now, if the snowpack stays strong into the spring and the river runoff continues to flow as predicted, a shortage could be delayed for two to three years past 2012, said Dan Bunk, a Bureau of Reclamation hydrologist in Boulder City, Nevada…

Cascade Geyser, Upper Geyser Basin, Yellowstone National Park, Wyoming. National Park Service