March rain, snow eases drought in Northwest
By John O’Connell
Drought conditions have improved dramatically over the last two months in much of the West.
But with critically low reservoirs, a small snowpack and low precipitation, California continues to face a dire outlook.
Following consecutive wet months, Washington state’s mountain snowpack is near normal, and Idaho water managers, who warned of possible irrigation curtailments in January, are now planning for the likelihood of flood control releases because of excess runoff.
Though a wet February and March has also improved the water outlook in Oregon and California, officials with the USDA Natural Resources Conservation Service say parts of those states still face considerable deficits.
Washington received twice its average March moisture, though much fell as rain, said Scott Pattee, the state’s NRCS water supply specialist. Washington’s statewide snowpack started the month at 94 percent of normal and is now near 100 percent — ranging from 85 percent of normal in the Olympic Peninsula to 125 percent in the Walla Walla watershed.
Pattee warns the “maturity” of the snowpack is two to three weeks ahead of schedule, and peak spring flows could come early.
Pattee said the crop season is poised to start with abundant soil moisture, thanks to heavy rainfall, and the reservoirs should all fill.
“I don’t see that there’s going to be any water shortage problems at all in Washington this year,” Pattee said.
Idaho basins also fared well, with the Upper Snake Plain receiving 150 percent of average precipitation, the Clearwater Basin at 175 percent of normal, the Willow, Blackfoot and Portneuf basins at 142 percent of normal and the Boise Project at 101 percent of normal.
Lynn Tominaga, executive director of Idaho Ground Water Appropriators, worried at the start of February he’d have trouble finding surplus water to buy to satisfy a Surface Water Coalition call against groundwater users.
“We’re probably not going to have to buy any at all,” Tominaga said. “It just shows you how much change can happen in a two-month period. In January, they were talking about dry reservoirs, and all of a sudden February and March come and everything is full or will be full.”
Ron Abramovich, Idaho NRCS water supply specialist, said the Owyhee Basin got 140 percent of its average March moisture, but most fell as rain, and the snowpack remains just 57 percent of normal.
Steve Howser, general manager of Idaho’s Aberdeen-Springfield Canal Co., said storms on March 31 and April 1 brought snow, which melts gradually and should help offset a soil-moisture deficit in his area following a dry fall.
“It’s not as likely I’ll have to crank up to 75 percent of my full diversion early in the season. Because there’s water in the ground, my demand is down,” Howser said.
Some southeast Idaho growers with deep wells had already started watering their winter wheat prior to the recent storms, and spring wheat planting started in the region around March 20. American Falls grower Kamren Koompin said early planted spring wheat has already emerged. The rest will be planted on a more normal schedule, due to the snow storms.
“It’s been good precipitation since Feb. 1, but really in the valley we were a little dry. We got in the field a little ahead of normal,” Koompin said.
If flood control releases are necessary, Howser said the state may ask his company to assist with aquifer recharge.
“We are looking at being very close to filling the (Upper Snake reservoir) system. We’ll recover from the last few years,” said Roland Springer, assistant area manager of the Bureau of Reclamation’s Upper Snake Field Office. “What we’re looking at now is the potential of flood-control operations.”
Rex Barrie, Boise River watermaster, sent an email to growers that he expects Arrowrock and Lucky Peak reservoirs to be full, and projections are for Anderson Ranch Reservoir to be 70-80 percent full.
Julie Koeberle, an Oregon NRCS hydrologist, said her state’s March precipitation ranged from 134-182 percent of average, but statewide mountain snowpack, at 61 percent of average, remains “pretty poor for this time of year.”
The snowpack is near average throughout much of Northern Oregon’s high-elevation terrain. Below 5,000 feet, much of Oregon’s March moisture fell as rain, which nonetheless filled most reservoirs to average and above-average levels. Reservoirs in Lake County and the Owyhee and Malheur basins are the exception, with levels ranging from 35 to 65 percent of average.
The low-elevation Rogue, Umpqua and Klamath basins received about 150 percent of their normal March precipitation but have a meager 35-percent-of-average snowpack, up from 20 percent at the beginning of February. Central Oregon’s snowpack is 55-60 percent of normal.
Cary Penhollow, watermaster of Central Oregon Irrigation District in Redmond, said both of his district’s reservoirs are now full, but he’ll keep a close eye on river flows, and the state has declared a drought emergency for adjacent Crook County.
“Some of the storms that came in and the rain after them really made a huge difference,” Penhollow said. “We’re not at this point thinking about rationing.”
Ironically, heavy rains late last month delayed field work in the Willamette Valley.
Vegetable farmers in Oregon’s Willamette Valley were able to plant a few acres of peas before a near-record deluge in March, but have largely been on hold for the past couple weeks, said Chuck Palmquist, vice president of sales and services at Norpac Foods, a farmers’ cooperative.
Growers who contract with Norpac’s processing facilities in Hermiston, Ore., and Quincy, Wash., are doing well, but Willamette Valley growers were stymied, Palmquist said.
“I think our growers are getting a little bit frustrated at sitting on the sideline right now,” he said.
The valley’s grass seed growers were fertilizing and some were replanting sections damaged by last fall’s dry spell or winter cold, but the heavy rain put a temporary stop to that, said Roger Beyer, executive director of the Oregon Seed Council.
“Every dry day in the spring is critical for grass seed growers,” Beyer said. “There’s fertilizer to get on and sprays to get out.”
While recent storms have prompted water agencies to boost pumping, a snow survey April 1 offered little hope of long-term relief from California’s crippling drought.
California’s statewide snowpack is 44 percent of normal, with the Northern California snowpack at 35 percent of normal.
State and federal officials said storms that dumped more than an inch of rain on the Sacramento airport in the last week of March would enable them again to increase pumping from the Sacramento-San Joaquin River Delta, as they did during wet periods in February and early March.
The DWR, the U.S. Bureau of Reclamation and other agencies on March 31 turned up the spigot from 1,500 cubic feet per second to as much as 6,500 cfs and expected to maintain the higher level for at least a week, DWR director Mark Cowin said.
But officials cautioned that although the snowpack in the Sierra Nevada range received a boost from late-season storms, its meager water content still promises a gloomy summer for California farms and many communities.
Rain was expected to continue through the week in some northern areas before a high-pressure ridge returned over California this weekend, with the next system possibly appearing by the end of next week, National Weather Service meteorologist Holly Osborne said.
“Every little bit helps, but for a lot of areas we were still below normal precipitation for March, and for the year we’re still looking at below-normal precipitation,” Osborne told the Capital Press. “It was like that the last couple of years, too. It’s hard to make up that deficit, especially when we’re not even getting normal precipitation.”
Reporters Tim Hearden and Eric Mortenson contributed to this report.