Snow maintained most of its water content during heatwave

(May 4, 2023) – Despite the recent heatwave, Nevada Irrigation District (NID) snow courses are 230 percent of average.

District hydrographers measured an average of 61.8 inches of snow water content during their May survey, even though a major warm-up drove temperatures in the Sierra Nevada late last month. The historical May 1 average water content is 26.9 inches.

“Despite a drier than normal May and warming late last month, the snowpack has maintained most of its water content. The peak of the snowmelt is yet to come,” said NID’s Water Resources Superintendent Thor Larsen.  

“Snowmelt will accelerate in May and we're hopeful for below-average temperatures to carry the runoff period into June. The District asks the public to use caution around waterways, which will continue their dangerously high, cold flows,” Larsen said. 

NID conducts its snow surveys on five snow courses of varying elevation that provide water to raw- and treated water customers. 

The May survey found snow depth at Bowman Reservoir was 74.2 inches, while the water content equivalent was 36.1 inches. By comparison, the April survey measured 107.2 inches snow depth with a water content equivalent of 47.4 inches. 

Seasonal precipitation at Bowman stands at 90.44 inches, which is 140 percent of average, as of May 1.

District reservoir storage is also above average. NID’s nine reservoirs are currently storing 249,054 acre-feet of water, which is 92 percent of capacity and 107 percent of average.

In total, April precipitation was 1.79 inches, which is 31 percent of average for the month.

Here are the specifics of the snow survey:

• NID’s highest course, Webber Peak, at 7,800 feet, had 150.6 inches of snow with a water content of 82.4 inches (survey taken on April 27)
• English Mountain snow course (7,100 ft.) had 143.8 inches of snow with a water content of 77.7 inches (survey taken on April 26)
• Webber Lake (7,000 ft.) had 115.3 inches of snow with a water content of 59 inches (survey taken on April 27)
• Findley Peak (6,500 ft.) had a snowpack of 109.5 inches and a 54-inch water content (survey taken on April 26)
• Bowman Reservoir (5,650 ft.) had 74.2 inches of snow and a 36.1-inch water content (survey taken on April 26)
• At the lower Chalk Bluff snow course (4,850 ft.) on the Deer Creek watershed, the survey showed 2.3 inches of snow with a 1-inch water content on May 2 (the Chalk Bluff numbers are not included in the total average).

Snow water equivalent is an indicator of how much water the snowpack contains. This helps water managers plan for water use.

NID is a member of the California Cooperative Snow Survey. Results of the District’s snow surveys are used to predict water availability locally and statewide.