Spring Snake River flows looking surprisingly normal
As of now the conditions for fishing on the Snake River are as good as they can be and the Spring Snake River Flows are still normal and clear.
POSTED: TUESDAY, APRIL 14, 2015 4:30 AM
By Mike Koshmrl Jackson Hole Daily | 0 comments
Jackson Lake and Palisades Reservoir are holding more water than usual, and the surplus of storage has water managers anticipating normal Snake River spring flows despite the dwindling snowpack.
As of Monday, Jackson Lake’s nearly 850,000-acre-foot capacity was 77 percent accounted for, Bureau of Reclamation databases show. Palisades’ 1.2-million acre-feet of water storage was 90 percent occupied.
The snowpack in the Wyoming portion of the Snake River basin, meanwhile, had fallen to 84 percent of the long-term median and is on the verge of a significant melt.
“The April-through-July inflow forecast is 75 percent of normal for Jackson Lake and 78 percent of normal for the Snake above Heise [Idaho],” said Mike Beus, the bureau’s Upper Snake Basin water operations manager. “You compare our system storage with average and we have just enough water to make up for that forecast deficit.
“So we’re not in dire straits on the Snake,” Beus said. “We’re the envy of some of our neighbors.”
He attributed the fuller-than-normal reservoirs to spring 2014’s sizable snowpack, August rains and the strong “base flows” that have resulted.River gauges in the Jackson Hole area show that stream flows are running slightly high compared to normal for mid-April.
The Snake at its confluence with Flat Creek was running at 1,950 cubic feet per second Monday, which is about 16 percent above the median, according to U.S. Geological Survey monitors.
The Buffalo Fork was running high at 246 cfs, about 30 percent higher than normal. Also further north, Pacific Creek was gauged at 149 cfs Monday — some 80 percent higher than normal for April 13 historically.
But the big melt, Beus said, has not yet started, and snowfields at higher elevations are intact.
“Snowmelt is not started yet at 8,000 feet and above,” he said, “but I’m certain that the snow is ripe and closer to the onset of runoff than it would usually be at this time.
“At 8,000 feet we’re right on the verge,” Beus said. “We’ve got a lot of thermal energy in snow, pushing it down the mountain.”
The snowpack at the highest elevations in the basin — those above 9,500 feet — don’t typically begin to melt off for another month, he said.
Elsewhere in Wyoming, water and runoff is looking slightly less sparse than in Jackson Hole.