More hot and dry weather is expected to hang around the Pacific Northwest, exacerbating drought conditions that have gripped the region.
As of Aug. 28, every corner of Oregon, Washington state and Idaho is experiencing some stage of drought, from “abnormally dry” to “extreme,” according to the latest U.S. Drought Monitor.
The result is a summer filled with wildfires belching smoke that has impacted air quality for days at a time, and low stream flows prompting water regulators to curtail deliveries in some basins.
Washington state is seeing below-average flows in nearly half of all rivers and streams. Temperatures have also averaged about 3 degrees above normal statewide in July, making the period between May and June the fourth-warmest on record.
The watersheds draining the southwest side of the Olympic Range are at a record low, according to the U.S. Geological Survey. Streams also are under stress in Southwest Washington, with the Naselle River on Aug. 30 running at 33.2 percent of its 88-year average for that date.
Jeff Marti, drought coordinator for the Washington Department of Ecology, said the state is going through a significant precipitation deficit, which is being most felt in the west and southwest portions of the state.
“We have some rivers that have been establishing record low flows for this day of the year throughout the summer,” Marti said.
The Department of Ecology has been curtailing water for some 88 users in the Chehalis River Basin since late May and early June. State officials, however, have not gone as far as to declare a drought emergency.
The worst conditions appear to be in Western Oregon, which is reeling from a historic lack of rainfall in some areas. The National Weather Service reports the city of Salem had gone 78 straight days without any significant rain as of Aug. 29, and will likely break the record of 79 consecutive days set in 1967. Other parts of the region did get a few light showers Aug. 25-27.
Overall, Oregon precipitation is averaging 86 percent of normal, while stream flows are averaging less than 50 percent of normal — ranging from 30 percent in the John Day Basin to almost 80 percent along the South Coast.
Oregon Gov. Kate Brown has declared a drought emergency in nine counties: Lincoln, Douglas, Klamath, Lake, Harney, Grant, Wheeler, Baker and Morrow. Ken Stahr, surface water program manager for the Oregon Water Resources Department, said he has been surprised by how widespread this year’s drought is.
“I think we saw some of this coming over the winter,” Stahr said, referring to low mountain snowpack and rapid snowmelt in May. “We had kind of a late series of storms where we thought it may help. But by May, it was gone.”
Ivan Gall, administrator for the Field Services Division at OWRD, works with the 21 local watermasters across the state. He said they have largely had to begin regulating water deliveries sooner, curtailing junior users to satisfy senior water rights holders.
“We’ve had to cut deeper into the list of junior users more quickly than compared to normal precipitation years,” Gall said.
Drought conditions are creeping east into Idaho as well. About 70 percent of the state is listed as “abnormally dry,” and the remaining 30 percent is in “moderate drought.”
The National Oceanic and Atmospheric Administration’s Climate Prediction Center is calling for an increased likelihood of more unseasonably warm weather across all three states for the next three months, and likely below-average precipitation in most of Oregon and Washington.
The longer drought lingers, the more it will heighten anxiety over reservoir storage heading into next year, Marti said.
“You could have a vast recovery, or there could be some anxiety if we have a sub-par snowpack year,” he said. “You like to have good carryover. It gives you a little cushion heading into next year.”
Philip Mote, director of the Oregon Climate Change Research Institute at Oregon State University, said based on forecasts, the Northwest drought will not be easing up soon, and in fact more areas in eastern Washington may actually start developing more severe conditions.
In many ways, Mote said this year is reminiscent of 2015, another drought year amplified by low snow and spring precipitation. Some coastal streams in Oregon have lower flows this year than they did in 2015, Mote said.
“For anything relying on snowpack, that was a difficult year,” Mote said.