State snowpack still above average
Something to think about as you shovel the 4 inches of “mostly cloudy” off your driveway: The statewide snowpack actually decreased in January.
According to the latest snow surveys from the U.S. Department of Agriculture’s Natural Resources Conservation Service, Colorado’s statewide snowpack dropped from 136 percent of average on Jan. 1 to 117 percent of average on Feb. 1.
Allen Green, state conservationist with the service, said decreases were seen in all five of the major river basins, with the San Juan, Animas, Dolores and San Miguel basins in southwest Colorado experiencing the driest conditions during January.
Those areas, Green said, recorded only 25 percent of their normal January precipitation.
Green said similar drops were seen in the Gunnison Basin, where the snowpack dipped to 126 percent of average compared to 138 percent of average a year ago.
“Without those big storms back in December, most of the state would be well below average right now,” Green said. “At this point, they’ve allowed us to endure a dry month, yet maintain good snowpack readings nearly everywhere.”
He said statewide numbers were “considerably better” than at the same time in 2010 and similar to this time in 2009.
As of Feb. 1, statewide snowpack remains above average. The Colorado River basin is at 135 percent of average and nearly twice as deep (188 percent) as the 2010 Feb. 1 snowpack.
Reservoir storage in the Colorado Basin is at 112 percent of average while statewide it is 103 percent of average.
Statewide snowpack totals are currently tracking at 137 percent of those from a year ago.
“For a while in late December we saw the La Niña conditions go away and the weather went back to more normal pattern and we got pounded in the San Juan Basin,” said Mike Gillespie, state conservation service snow survey supervisor. “But since then it’s been pretty much shut off and we’ve seen our cushion go away as the percentages decrease.”
Facing the prospect of possible high spring runoff, the Bureau of Reclamation is making room in Blue Mesa Reservoir.
Water storage in Blue Mesa is at 108 percent of average.
Reservoirs across the Gunnison Basin were at 109 percent of the Feb. 1 average with snowpack readings at 126 percent of average, adding to a runoff estimate of 108 percent of average.
Colorado gets 80-percent of its snowfall from December through March, which means at least two more months of snow adding to what’s already a substantial snowpack.
“We should be able to make up a little ground,” Gillespie said. “But remember, this is only a forecast and things can change quite a bit between now and May 1,” the official end of the snow year.
With the prospect of high runoff in mind and desirous of ensuring plenty of storage room in Blue Mesa Reservoir, the Bureau increased releases from Crystal Reservoir by 300 cubic feet per second.
Releases will reach 800 cfs by late Tuesday, said Dan Crabtree, lead hydrologist at the bureau’s Grand Junction office.
He also said that should the spring runoff forecast hold, the Black Canyon Water Right 24-hour peak target flow would be 6,340 cfs.