Aspen Journalism is compiling a data dashboard highlighting metrics of local public interest, updated at least weekly by mid-day Tuesday.

Lake Powell is about two inches away from target elevation

Lake Powell‘s storage reached its lowest level recorded since it began filling in the 1960s and ’70s on March 13 when the reservoir was 24.41% of full.

Last week, on March 6, the reservoir was 24.62% of full. The reservoir’s capacity has fallen since last year, when on March 13, 2021, the reservoir was 37.22% of full.

The surface elevation of Lake Powell on March 13 was only about two inches above the target elevation of 3,525 feet as it hit a record low when the reservoir’s elevation dropped to 3,525.2 feet, or 174.8 feet from full pool. The reservoir had lost about one foot since March 6, when the elevation was at 3,526 feet from full pool. Last year, on March 13, the reservoir reached 3,569.34 feet or 130.6 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. Last week, Aspen Journalism published a story on the the impact of last summer’s emergency releases designed to help Lake Powell.

Snowpack at Ivanhoe and Schofield Pass remain above historical averages

SNOTEL sites that monitor snowfall throughout the winter measured the snowpack at Independence Pass at 83.9% of average on March 13, with a “snow water equivalent” (SWE) of 12.09 inches. The size of the snowpack relative to the 30-year average is up from 82.7% on March 6. Last year on March 13, the SNOTEL station up the pass recorded an SWE of 11.3 inches.

The monitoring station at the lower-elevation McClure Pass recorded an SWE of 13.5 inches, or 83.9% of average, on March 13. A week before, the station reported 12.52 inches of water contained in the snowpack, or 82.4% of average. Last year, on that same day, the station measured a snowpack holding 11.61 inches of water, or 72.1% of average.

On the northeast side of the Roaring Fork Basin, snowpack at Ivanhoe contains higher water levels than the 1991-2020 average, with 13.7 inches on March 13, which is 103% of the average of 13.3 inches. It’s also up from last year’s 12.4 inches of SWE.

Snowpack at Schofield Pass reached 34.69 inches on March 13, which represents 115.2% of average. Schofield Pass, which sits at an elevation of 10,700 feet between Marble and Crested Butte, picked up more than one inch 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.

Maximum air temperature averaging 37°F during the first week of March

Temperatures dropped from a high of 55°F on March 3, which is about 16 degrees above normal, to a high of 22°F on March 7, which is about 18 degrees below normal, before going back up to 38°F on March 9, according to temperatures recorded at the Aspen/Pitkin County Airport. The minimum decreased from 26°F on March 5 to -1°F on March 8 before reaching 17°F on March 9.

Clean air reported in Aspen

The air quality in Aspen was “good” this past week. The AQI index for ozone ranged from 42 on March 7 to 47 on March 11.

Laurine Lassalle

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,...