SULTAN — For the first time in several years, there is more than enough mountain snow to feed rivers in Snohomish County’s Sultan Basin through the summer.
A helicopter carried three Snohomish County Public Utility District workers to ridges around Spada Lake last month to measure the snow’s depth and how much water it is holding. This year’s depth is 117 percent of the average measured since the PUD began the annual snowpack survey in 1986.
That is a nice change from the past couple of years, said Mark Flury, a senior engineer at the PUD.
Last year, the utility recorded snow levels less than 80 percent of the average from previous years. In 2015, the PUD workers found no snow at any of the three measurement locations. That had never happened before. While there was scant snow in the mountains that year, there was heavier than usual rain. Water use did not have to be restricted.
The district uses the snowpack information to figure out how much water will be in Spada Lake in late summer and early fall. Spada Lake feeds the PUD’s Jackson hydropower station, which provides about 5 percent of the district’s power supply. It also has small dams on Youngs and Woods creeks.
Spada Lake Reservoir also provides about 80 percent of the county’s drinking water, which is managed by the city of Everett. The lake holds more than 50 billion gallons. That is more than 10 percent of all the water used in the United States in a single day, according to the U.S. Environmental Protection Agency.
The high snow levels mean there should not be concerns about water shortages this year, Flury said. Though, he cautioned, “we don’t have a huge oversupply.”
The PUD measures snow depths and water content at three sites: Kromona Mine at 2,400 feet elevation, Olney Pass at 3,300 feet and Stickney Ridge at 3,600 feet. The depth is measured by sinking a long, hollow tube marked with inches and feet into the snow. It is then pulled out and weighed to figure out the amount of water held in the snow.
This year’s snowpack is higher than normal for most of the West, meteorologist Cliff Mass reported on his Weather Blog on March 25.
The snow in Washington is so deep that the state’s Department of Transportation has delayed opening the North Cascades Highway. The department announced in late March that it could be June before it gets all the snow off the road.
Dan Catchpole: 425-339-3454; firstname.lastname@example.org; Twitter: @dcatchpole.