Aspen Journalism is compiling a data dashboard highlighting metrics of local public interest, updated weekly.
Snowpack still above average
Snowpack in the Roaring Fork basin reached 117% of average for Feb. 19 or 124% of median with 14.8 inches of snow-water equivalent, according to NOAA.
SNOTEL sites that monitor snowfall throughout the winter measured the snowpack at Independence Pass at 95% of average on Feb. 19 with a “snow water equivalent” (SWE) of 11.4 inches, up from 10.9 inches on Feb.12. Last year on Feb. 19, the SNOTEL station up the pass (located at elevation 10,600 feet) recorded an SWE of 9.7 inches.
The monitoring station at McClure Pass located at elevation 9,500 feet recorded a SWE of 18 inches on Feb. 19, or 141.7% of average. That’s up from a SWE of 16.5 inches on Feb. 12. Last year, on Feb. 19, the station measured a snowpack holding 9.4 inches of water.
On the northeast side of the Roaring Fork Basin, snowpack at Ivanhoe, which sits at an elevation of 10,400 feet, reached 12 inches of SWE on Feb. 19, or 109.1% of average.
Snowpack at Schofield Pass reached 28.6 inches on Feb. 19, which represents 120.2% of average. 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.
Low temperature down to -12°F
High air temperatures at the Aspen airport dropped from 44°F on Feb. 12 to 20°F on Feb. 16 before going up to 32°F on Feb. 17, which is about three degrees below normal. Meanwhile, low temperatures increased from -8°F on Feb. 10 to 15°F on Feb. 14 before dropping to -12 on Feb. 16, which is about 21 degrees below normal.
Lake Powell’s elevation keeps dropping
Lake Powell‘s storage is at its lowest level recorded since it began filling in the 1960s. On Feb. 19, the reservoir was 22.03% full (with a total capacity based on a 1986 sedimentation survey) or 22.98% full (based on updated 2017-18 sedimentation data). That’s down from Feb. 12, when the nation’s second-largest reservoir was at 22.17% of capacity (1986 data) or 23.13% (based on 2017-18 data).
On July 1, 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.
The reservoir’s capacity has fallen since last year, when on Feb. 19, 2022, it was 25.24% full (based on 1986 data).
On Feb. 19, Lake Powell’s elevation reached 3,521.7 feet, or 178.3 feet from full pool, down from 3,522.3 feet on Feb. 12. The reservoir’s water level on Feb. 19 was 3.3 feet below the target elevation of 3,525. In the last water year, Powell’s surface elevation peaked at 3,539.84 feet on July 3, after it dipped to what was then its lowest level since filling of 3,522.24 on April 22. Last year, on Feb. 19, the reservoir reached 3,528.41 feet in elevation, or 171.59 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 remains clean in Aspen
The air quality in Aspen was “good” last week with an AQI index ranging from 29 for PM2.5 on Feb. 17 to 46 for ozone on Feb. 19.