Aspen Journalism is compiling a data dashboard highlighting metrics of local public interest, updated at least weekly by mid-day Tuesday.
Snowpack at Indy, McClure passes dips slightly below historic averages
SNOTEL sites that monitor snowfall throughout the winter measured the snowpack at Independence Pass at 98.9% of average on Jan. 23, with a “snow water equivalent” (SWE) of 9.09 inches. With volume up only slightly since last week, the size of the snowpack relative to the 30-year average is down from at 104.7% on Jan. 16. Last year on Jan. 23, the SNOTEL station up the pass recorded an SWE of 6.61 inches.
The monitoring station at the lower-elevation McClure Pass recorded an SWE of 8.9 inches, or 95.7% of average, on Jan. 23. A week before, the station reported 8.7 inches of water contained in the snowpack, or 102.4% of average. Last year, on that same day, the station measured a snowpack holding 4.49 inches of water, or 48.3% of average.
On the northeast side of the Roaring Fork Basin, snowpack at Ivanhoe contains higher water levels than the 1991-2020 average, with 10.31 inches on Jan. 23, which is 124.3% of the average of 8.3 inches. It’s also up from last year’s 6.42 inches of SWE.
Snowpack at Schofield Pass reached 24.88 inches on Jan. 23, which represents 139.8% of average. Schofield Pass, which sits at an elevation of 10,700 feet between Marble and Crested Butte, has gained over 15 inches of SWE since Dec. 23.
“It looks like the storm system at the end of December may have just hit the western half of the Elk Mountains with more snow than further east,” Karl Wetlaufer, hydrologist and assistant snow survey at the U.S. Department of Agriculture-Natural Resources Conservation Service, wrote in an email.
Even lower elevation sites, like North Lost Trail and all of the Fryingpan basin sites, received substantial accumulations during that storm, according to Wetlaufer. North Lost Trail, located at 9,200 feet to the north of Schofield Pass, recorded a snowpack holding 13.5 inches of water, or 143.7% of average on Jan. 23.
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 level is getting close to critical elevation
The U.S. Bureau of Reclamation announced on Jan. 7 that 350,000 acre-feet of water will be held back in Lake Powell from January to April instead of being released downstream to Lake Mead. The 350,000 acre-feet of water will reach Lake Mead later this year, between June and September after the spring runoff occurs.
“Without the changes to monthly water releases, the reservoir’s elevation was projected to steadily decline below the target elevation through the winter months,” a bureau press release noted.
Lake Powell‘s storage reached its lowest level recorded since it began filling in the 1960s and ’70s on Jan. 23, when the reservoir was 26.45% of full.
Last week, on Jan. 16, the reservoir was 26.8% of full. The reservoir’s capacity has fallen since last year, when on Jan. 23, 2021, the reservoir was 40.12% of full.
The surface elevation of Lake Powell is only eight feet above the target elevation of 3,525 feet as it hit a record low on Jan. 23, 2022, when the reservoir’s elevation dropped to 3,533.1 feet, or 167 feet from full pool. The reservoir has lost more than a foot since Jan. 16, when the elevation was at 165.58 feet from full pool. Last year, on Jan. 23, the reservoir reached 3,579.14 feet or 122.14 feet from full pool.
Air temperature close to normal
Temperatures increased last week, from a high of 31°F on Jan. 15, which is 1.8 degrees below normal, to a high of 41°F on Jan. 16, which is 8.2 degrees above normal, before decreasing to 36°F on Jan. 19, according to temperatures recorded at the Aspen/Pitkin County Airport. The minimum dropped from 17°F on Jan. 14 to 4°F on Jan. 16, which is 2.9°F below normal.
Clean air reported in Aspen
The air quality in Aspen was “good” this past week. The AQI index for ozone ranged from 39 on Jan. 18 to 43 on Jan. 20 and 23.