Aspen Journalism is compiling a data dashboard highlighting metrics of local public interest, updated weekly.

The Fork peaked on Friday

The upper Roaring Fork River saw its highest streamflows of the season on June 23. At Stillwater, located upstream of Aspen, the Roaring Fork River ran as high as 842 cfs on June 23, or 200% of average, before dropping to 559 cfs on June 25, or 138% of average. Last week, the river ran at 242 cfs, or 52.8% of average.

This rise in streamflow is due to an increase in temperatures and the Twin Lakes Tunnel diversion being temporarily shut down due to water rights constraints.

The tunnel that sends Roaring Fork flows east of the Continental Divide was running at 1.6 cfs on June 25, while on June 18, 295 cfs was flowing through the tunnel.

The USGS sensor below Maroon Creek recorded the Fork running at 1,520 cfs, or 187.9% of average, on June 25 after reaching 1,720 cfs on June 23. That’s up from 976 cfs on June 18.

At Emma, below the confluence with the dam-controlled Fryingpan, the June 25 streamflow of 2,190 cfs represented about 128.1% of average. That’s down from 2,620 cfs on June 23, or 148% of average, and down from 1,680 cfs, or 90.3% of average, on June 18.

Meanwhile, the Crystal River above Avalanche Creek, which is not impacted by dams or transbasin diversions, flowed at 1,940 cfs or 152.8% of average on June 22 before dropping to 1,570 cfs, or 130.8% of average. Last week, the river ran at 1,270 cfs, or 100% of average.

The Colorado River ran at 13,00 cfs at Glenwood Springs, or 135.4% of average, on June 25, up from 11,300 cfs last week, while the Colorado flowed at 23,000 cfs near the Colorado-Utah stateline, or 160.8% of average.

Aspen Journalism is compiling real time streamflow data. You can find all the featured stations from the dashboard with their real-time streamflow on this webpage.

Roaring Fork snowpack has melted

Snowpack at the SNOTEL stations located at Independence Pass (elevation 10,600), McClure Pass (8,770), Ivanhoe (10,400) and North Lost Trail (9,219) is gone.

Meanwhile, snowpack at Schofield Pass is holding 0.1 inches of water on June 25. Schofield Pass sits at an elevation of 10,700 feet between Marble and Crested Butte.

Snow water equivalent — the metric used to track snowpack — is the amount of water contained within the snowpack, which will become our future water supply running in local rivers and streams.

Lake Powell’s water levels has gained five feet in the past 10 days

Lake Powell‘s water levels began their seasonal rise in mid-March as warming temperatures initiated snowmelt, after the reservoir in the winter dropped to its lowest level on record since filling. On June 25, the reservoir was 38.66% full (with a total capacity based on a 1986 sedimentation survey) or 40.33% full (based on updated 2017-18 sedimentation data). That’s up from June 16, when the nation’s second-largest reservoir was at 36.99% of capacity (1986 data) or 38.58% (based on 2017-18 data).

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 published a story explaining the that drop in storage due to sedimentation.

Last year, on June 25, 2022, the reservoir was 28.11% full (based on 1986 data).

On June 25, Lake Powell’s elevation reached 3,581.4 feet, or 118.7 feet from full pool, up from 3,576.2 feet on June 16. Last year, on June 25, the reservoir reached 3,539.18 feet in elevation, or 160.82 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.

High air temperatures reach 80°F

High air temperatures at the Aspen airport increased from 57°F on June 17 to 80°F on June 22, or about four degrees above normal. Meanwhile, low temperatures ranged between 35°F and 45°F in the past two weeks.

Moderate air quality recorded in Aspen last week

The air quality in Aspen was “moderate” last week — except for June 21, 22 and 25 when the AQI index ranged from 25 for PM2.5 to 50 for ozone. For the remainder of the week, Aspen’s index for ozone went from 51 on June 20 to 77 on June 19.

Laurine Lassalle is Aspen Journalism’s data desk editor, where she works to catalogue and analyze local public data. She also heads our our “Tracking the Curve” project, documenting COVID-19 in Pitkin,...