Aspen Journalism is compiling a data dashboard highlighting metrics of local public interest, updated at least weekly by mid-day Tuesday.
Lake Powell is only one foot away from dropping below target elevation
The U.S. Bureau of Reclamation announced on March 5 that Lake Powell will decline below 3,525 feet in elevation in the near future, reflecting a dry winter season. “The drop is temporary and Lake Powell’s elevation is expected to recover above 3,525 feet through the course of the spring runoff season, likely in May,” the press release noted.
Lake Powell could drop 2 to 3 feet below the target elevation in March, according to recent projections. “A very dry January and February eroded the Colorado River Basin’s snowpack, decreasing Lake Powell’s projected unregulated inflow forecast for water year 2022 by approximately 2.2 million acre-feet from January through February,” according to the press release.
Lake Powell‘s storage reached its lowest level recorded since it began filling in the 1960s and ’70s on March 6, when the reservoir was 24.62% of full.
Last week, on Feb. 27, the reservoir was 24.92% of full. The reservoir’s capacity has fallen since last year, when on March 6, 2021, the reservoir was 37.59% of full.
The surface elevation of Lake Powell is only one foot above the target elevation of 3,525 feet as it hit a record low on March 6, 2022, when the reservoir’s elevation dropped to 3,526 feet, or 174 feet from full pool. The reservoir has lost about one foot since Feb. 27, when the elevation was at 3,527.18 feet from full pool. Last year, on March 6, the reservoir reached 3,570.45 feet or 129.55 feet from full pool.
The “minimum power pool” for turbines generating hydropower at the Glen Canyon 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.
Snowpack at Indy Pass remains at over 80% of average
SNOTEL sites that monitor snowfall throughout the winter measured the snowpack at Independence Pass at 82.7% of average on March 6, with a “snow water equivalent” (SWE) of 11.42 inches. The size of the snowpack relative to the 30-year average is down from 84.5% on Feb. 27. Last year on March 6, the SNOTEL station up the pass recorded an SWE of 10.98 inches.
The monitoring station at the lower-elevation McClure Pass recorded an SWE of 12.52 inches, or 82.4% of average, on March 6. A week before, the station reported 11.69 inches of water contained in the snowpack, or 83.5% of average. Last year, on that same day, the station measured a snowpack holding 10.98 inches of water, or 72.3% of average.
On the northeast side of the Roaring Fork Basin, snowpack at Ivanhoe contains higher water levels than the 1991-2020 average, with 12.91 inches on March 6, which is 101.7% of the average of 12.7 inches. It’s also up from last year’s 12.2 inches of SWE.
Snowpack at Schofield Pass reached 33.31 inches on March 6, which represents 117.7% of average. Schofield Pass, which sits at an elevation of 10,700 feet between Marble and Crested Butte, picked up 3.11 inches of SWE since last week.
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.
Temperature rose between late-February and early-March
Temperatures jumped from a high of 20°F on Feb. 24, which is 16.9 degrees below normal, to a high of 49°F on March 1, which is about 11 degrees above normal, according to temperatures recorded at the Aspen/Pitkin County Airport. The minimum increased from -4°F on Feb. 27 to 11°F on March 1.
Air quality in Aspen remains “good”
The air quality in Aspen was “good” this past week. The AQI index ranged from 21 for PM2.5 on March 2 to 50 for ozone on Feb. 28.