Aspen Journalism is compiling a data dashboard highlighting metrics of local public interest, updated at least every Tuesday. Check back for updates as we add more features.

Snowpack at Independence Pass is approximately 80% of average for this time of year

SNOTEL sites that monitor snowfall throughout the winter show the snowpack at Independence Pass at 79.7% of average on Nov. 28 with a “snow water equivalent” (SWE) of 3.11 inches. Last year on the same date, the SNOTEL station up the pass recorded an SWE of 3.19 inches.

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.

The monitoring station at McClure Pass recorded an SWE of less than one inch, or 33.5% of average, on Nov. 28. Last year, on that same day, the station measured a snowpack holding 1.81 inches of water, or 67.1% of average.

On the other side of the Roaring Fork Basin, snowpack at Ivanhoe contains more water than the 1991-2020 average with 4.09 inches on Nov. 28, compared to an average of 3.4 inches.

According to the Roaring Fork Conservancy’s snowpack report of Nov. 24, snowpack in the Roaring Fork Watershed is 80% of average for this time of the year.

Local streams flowing close to last year’s rates

The USGS gauge on the Roaring Fork near Aspen at Stillwater, located upstream of town, measured streamflow at 16.3 cfs on Nov. 28, which represents 54.3% of average. A week before, the river was flowing at 17.4 cfs. On Nov. 28, 2020, the river ran at 12.2 cfs.

The ACES gauge, located near the Mill Street Bridge in central Aspen, measured the Roaring Fork at an average of 20.08 cfs on Nov. 28, up from 21.23 cfs on Nov. 21. The river ran at 17.3 cfs on that day last year.

The Crystal River above Avalanche Creek, near Redstone, flowed at 62 cfs, or 100.1% of average on Nov. 28, which is down from 65 cfs on Nov. 21. That’s up 72% from the streamflow last year, when the river ran at 36 cfs on Nov. 28, 2020. The Crystal River at the CPW Fish Hatchery bridge ran at 71.7 cfs on Nov. 28. That puts the river below the minimum instream flow set at 100 cfs set by the 1979 water rights decree.

Lake Powell keeps drying up

Lake Powell could potentially fall below minimum power pool in 2022, which is an elevation of 3,490 feet, according to the U.S Bureau of Reclamation. “Should extremely dry hydrology continue into next year, Lake Powell could reach elevation 3,490 feet as early as July 2022,” the press release noted.

Lake Powell‘s storage kept getting lower this past week, reaching its lowest level recorded since it began filling in the 1960s and ’70s on Nov. 28, when the reservoir was 28.9% of full.

Last week, on Nov. 21, the reservoir was 29.08% of full. The reservoir’s capacity has fallen since last year, when on Nov. 28, 2020, the reservoir was 43.74% of full.

The surface elevation of Lake Powell is also in decline and hit a record low on Nov. 28, 2021, when the reservoir’s elevation dropped to 3,542 feet, or 158 feet from full pool. The reservoir has lost seven inches since Nov. 21, when the elevation was at 157.3 feet from full pool. Last year, on Nov. 28, the reservoir reached 3,587.99 feet or 112.01 feet from full pool.

Air temperature in Aspen drops

Last week, Aspen experienced a temperature drop, from a high of 54°F on Nov. 22, which is about 4 degrees above normal, to a high of 36°F on Nov. 24, which is 0.9 degrees below normal. Minimum temperature also decreased from 29°F on Nov. 20 to 15°F on Nov. 24 — the latter being 1.3 degrees above normal.

‘Good’ air quality reported last week in Aspen

The air quality in Aspen was “good” this past week. The AQI index for ozone ranged from 33 on Nov. 26 to 40 on Nov. 25 and 28.

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,...