Aspen Journalism is compiling a data dashboard highlighting metrics of local public interest, updated weekly.
Streamflows are up but sill below average
At Stillwater, located upstream of Aspen, the Roaring Fork River ran at 165 cfs on May 19, or 75.7% of average, up from last week when the river ran at 50.2 cfs and from 36.4% of average.
Water through the tunnel that sends Roaring Fork flows east of the Continental Divide ran at 108 cfs on May 19, up from 29.2 cfs on May 12.
The USGS sensor below Maroon Creek recorded the Fork running at 453 cfs on May 19, or 92.3% of average, up from 192 cfs and from 66% of average, on May 12.
At Emma, below the confluence with the dam-controlled Fryingpan, the May 19 streamflow of 820 cfs represented about 82.5% of average. That’s up from 474 cfs on May 12 and from 67.4% of average.
Meanwhile, the Crystal River above Avalanche Creek, which is not impacted by dams or transbasin diversions, flowed at 743 cfs or 87% of average. Last week, the river ran at 206 cfs, or 33.6% of average.
The Colorado River ran at 8,080 cfs at Glenwood Springs, or 107.9% of average, on May 19, up from 3,910 cfs last week, while the Colorado flowed at 13,100 cfs near the Colorado-Utah stateline, or 89.1% of average.
Lake Powell’s water levels on the rise
Lake Powell‘s water levels are up. On May 19, the reservoir was 34.24% full (based on updated 2017-18 sedimentation data). That’s up from May 12 when the nation’s second-largest reservoir was at 33.99%.
On July 1, 2022, the Bureau of Reclamation revised its data on the amount of water stored in Lake Powell, with a new, lower tally taking into account a 4% drop in the reservoir’s total available capacity between 1986 and 2018 due to sedimentation. Aspen Journalism in July 2022 published a story explaining the that drop in storage due to sedimentation. We will be now using the 2017-18 sedimentation data only.
On May 19, 2023, the reservoir was 28.86% full.
On May 19, Lake Powell’s elevation reached 3,562.7 feet, or 137.3 feet from full pool, which is up from 3,561.9 feet on May 12. Last year, on May 19 the reservoir reached 3,544.38 feet in elevation, or 155.62 feet from full pool.
The “minimum power pool” for turbines generating hydropower at the Glen Canyon Dam is 3,490 feet, and 3,525 feet has been set as a buffer to ensure that the reservoir and the turbines can continue to function properly.
Air temperatures are increasing
High air temperatures at the Aspen airport went from 49°F on May 11 to 67°F on May 13 then went down to 60°F on May 15 before reaching 67°F on May 16, or two degrees above normal. Meanwhile, low temperatures ranged from 29°F on May 11 to 37°F on May 14-15.