This article was published on: 01/11/17 12:00 AM
Early snapshot of snow, water levels show promise for Oregon
By Hilary Corrigan
Drivers and parents may be cursing Central Oregon’s heavy recent snowfall by now, but federal and state officials call it a good start of the season for snowpack and water supply.
They’re hoping it continues, at least in the mountains.
“A rainy fall followed by a snowy December has left Oregon’s mountains with above-normal snowpacks for the start of the New Year,” stated a Monday report from the Natural Resources Conservation Service in Oregon, part of the U.S. Department of Agriculture.
“It’s exactly where we want to be,” Scott Oviatt, snow survey supervisor with the conservation service in Oregon, said of snowpack conditions.
But Oviatt noted it’s early in the season and that a report in April will give a more definitive picture than the January report.
“It’s just a brief snapshot,” he said of the new report.
Snowpack refers to the mass of snow on the ground that will fill waterways as it melts — critical to waterways that sustain irrigation, fisheries and drinking water. The conservation service uses the measurement of snow water equivalent to determine the available water that would result from melting the snowpack. The conservation service takes measurements of snowpack, precipitation, temperature, wind, soil moisture and other factors at various sites through the state, using both automated data and manual surveys.
The report — the first of the season in a monthly series that runs through June — found an above-normal snowpack for Oregon overall, with a statewide average of 124 percent of normal on Monday.
The Upper Deschutes and Crooked river basins had a 126 percent of normal reading; the Malheur Basin had a 129 percent reading; and the Owyhee Basin had a 156 percent reading.
The report expects adequate water supplies for spring and summer for the state if the rest of winter continues its current wet, cold, snowy trend, and if the snow melts at a normal rate through spring. That was not the case last year, when record temperatures melted off a solid snowpack quickly and led to earlier peaks in river flows.
The report noted how variable storm patterns are causing the usual disparity in the level of snow at different sites. For instance, Southern Oregon and the Wallowa Mountains are storing below-normal amounts of snow. Meanwhile, many sites in Oregon saw the wettest October on record from rain — an ideal condition to prime the mountain soils before snowfall.
The report found that most reservoirs in the state now store below-average amounts of water, following the summer’s water use and below-normal streamflow. But reservoirs in the Deschutes and Crooked River basins are storing the highest amounts with 90 percent of average. The report expects average or above-average streamflow for the summer, based on the rainy fall, the snowy start of winter and such conditions continuing.
Kyle Gorman, region manager for the Oregon Water Resources Department, noted the report’s streamflow forecast for the Deschutes Basin ranges from about 100 percent to 118 percent of average. Gorman called that level “a really good place to be at this time.”
“A lot of things can change,” Gorman said. “But it’s looking good so far.”
He also noted the unusually high amount of snow for lower elevations, a level he hasn’t seen since the early 1990s. While the snow at lower elevations doesn’t do much to bolster streamflows, it does help keep soil moist so that, heading into spring, the ground is not as dry. Wetter soil at that time can help delay the start of irrigation or require less irrigation water to start the season.
Overall, it’s very important for precipitation and cold temperatures to continue to April, Gorman said — in the mountains, he added.