Low snowpack raises drought concerns
The mountain snowpack is 44 percent of normal in Washington and 31 percent of normal in Oregon, raising the specter of a summer drought, says a top water expert for Washington.
It’s still early enough that storms could increase snowpack to 80 percent of normal and drought would be avoided, said Scott Pattee, water supply specialist of the Washington Snow Survey Office of the USDA Natural Resources Conservation Service in Mount Vernon.
December normally is a pretty big snow month while January tends to be colder and drier, he said. Any area under 50 percent at the start of January has slim odds of fully catching up, he said.
“It’s very reminiscent of 2005, which is our last drought on record,” Pattee said. “The thing that saved us then was a wet, cool spring. It made for a long, slow melt and irrigation wasn’t needed as early.”
This fall was dry. Storms skirted Oregon and Central Washington but left more snow in Idaho and Montana, he said. Idaho’s snowpack is at 64 percent of normal and Montana’s is at 115 percent as of Jan. 6, he said.
Tree fruit and row crop growers in Central Washington depend on irrigation. Some orchards were torn out for lack of water in the Yakima Valley in 2005 and pears had insufficient water in the Wenatchee Valley. Water was short in the Methow River in the Okanogan.
As of Jan. 6, the upper Columbia region, from the Methow to the Canadian border, was 71 percent of normal, Pattee said. The central area from Lake Chelan southward was 44 percent, the upper Yakima from Snoqualmie and Blewett passes down was 40 percent and the lower Yakima from White and Chinook passes down the Naches River was 50 percent.
Washington’s low is 22 percent of normal in the Olympic Mountains and the high is 80 percent in the lower Snake River region and Blue Mountains, Pattee said.
“Oregon’s biggest concern is always the Klamath Basin because it’s way over allocated,” he said.
If snowpack doesn’t improve by Feb. 1, government agencies will grow concerned, and by March 1 the Washington Department of Ecology will be looking at stream allocations for junior water right holders, he said.
“If I were an irrigator, I would be watching,” Pattee said, “particularly on the Methow and Entiat where there is no storage (no water reservoirs).” The Entiat basin, north of Wenatchee, is at 25 percent of normal snowpack.
In 2005, Washington’s snowpack was 40 percent of normal on Jan. 6 and 33 percent on April 1. Oregon’s was 45 percent on April 1, Idaho 71 percent and Northern California 157 percent.
Other recent drought years were 2001, 1990 and 1977.