Scott Condon/The Aspen Times
Last year at this time, Tim Miller was pondering if there would be enough spring runoff to fill Ruedi Reservoir.
This year, the hydrologist with the U.S. Bureau of Reclamation has one of the beefiest snowpacks in at least 10 years to work with.
Miller oversees regulating the outflow of the reservoir 12 miles east of Basalt. It is his responsibility to fill the reservoir so water is available later in the year for irrigation and other uses.
He said droughts and abundant snow years all present their special challenges. Last year, he had to dial back releases to try to fill the tub. This year, he has to make sure he has enough room for the inflow.
“They’re all equally difficult,” Miller said this week. “It’s just difficult in a different way.”
He envisions Ruedi Reservoir filling during the first half of July, likely around July 4. The Bureau of Reclamation and two other agencies have forecast the amount of water flowing into the reservoir this year at 120 percent to 140 percent of average for April through July.
Miller said one thing that stands out this year is that the lower-elevation snowpack is so big in the Fryingpan Valley. The Kiln snow telemetry site, at 9,600 feet in elevation, was at 147 percent of median Thursday.
The Ivanhoe Lake site, at 10,400 feet, was at 168 percent of median. The last comparable snowpacks were in 2011, when winter wouldn’t end.
“In 2011, we continued to hold onto snow longer,” Miller said. “Storms just kept on coming.”
The inflow to the reservoir peaked at about 1,500 cubic feet per second in late June 2011 and stayed at about 1,300 cfs for several days. Releases from the dam were ramped up to 870 cfs, close to the maximum without causing flooding. The reclamation bureau warned town officials going into the Fourth of July weekend that it might have to boost releases from the dam even further. Town officials were prepared for at least minor flooding.
The inflow dropped just in time and faded fast. Flooding was averted.
This year, Ruedi Reservoir is lower than usual for this time of year in the aftermath of the drought of 2018. Extra water was required for fighting the Lake Christine Fire and late-season irrigation.
The reservoir was at about 55 percent full. While that isn’t a historically low level, it is 10,000 acre-feet lower than at this point last year and at this point in 2011, Miller said. Having the extra space compared with the big runoff year of 2011 is reassuring, he said.
Miller said he will keep the reservoir level hovering about where it is in anticipation of runoff starting soon.
The outlook for the reservoir is good for boaters because of the high probability it will fill right around July 4, Miller said.
The outlook for anglers on the lower Fryingpan River is less certain. Miller said the outflows from the reservoir will likely be higher from later this spring through July than they were last year. The flows in late summer and into fall will depend on the U.S. Fish and Wildlife Service’s plan for managing the Colorado River near Grand Junction for endangered fish species. Water from Ruedi Reservoir is often used to increase levels on the Colorado River.
The ideal situation this spring and summer would be slow, steady melting of the snowpack, producing a consistent inflow to the reservoir, according to Miller. But he knows Mother Nature will likely throw some curves.
“We never get that” ideal situation, he said.