Irrigation demand up along with Wickiup flows

May 13, 2015
Irrigation demand up along with Wickiup flows

Releases from reservoir upstream of Bend come early

By Dylan J. Darling / The Bulletin / @DylanJDarling

Natural river flows are down but irrigation demand has come early, so releases out of Wickiup Reservoir are above average for this time of year upstream of Bend on the Deschutes River.

“This year was warm and dry so demand increases significantly,” said Kyle Gorman, region manager for the Oregon Water Resources Department in Bend. Irrigation demand started in early April, he said, as it does in dry years in Central Oregon.

While farmers and ranchers drawing water from the Deschutes River benefit from a robust aquifer unlike their counterparts pulling from the Crooked River, water users relying on both rivers face restrictions in the form of allotments.

The North Unit Irrigation District draws from both rivers and in March established allotments, said Mike Britton, district general manager.

For the Deschutes River water users, the district allotted 2.2 acre-feet per acre, he said. For the Crooked River water users, the district allotted 1.25 acre-feet per acre. An acre-foot is enough water to submerge an acre of land under a foot of water. In a normal year, district water users are not subject to an allotment.

North Unit supplies about 850 to 900 water users on 53,722 acres supplied by the Deschutes River and 5,165 acres supplied by the Crooked River.

Britton said district officials try to be conservative in setting allotments, and more water could become available depending upon late spring and summertime weather, but the allotment for Crooked River water users in the district is slim.

“You can’t grow much with that,” he said. He said some growers relying on the Crooked might fallow some fields this year. In contrast, the allotment for Deschutes River water users in the district probably will be enough for a typical season.

Last year, the district also issued similar allotments, Britton said, the first in about a decade. Allotments come when irrigation starts early and districts turn to stored water, such as the water in Wickiup Reservoir, as a supply.

Drawing more water out of Wickiup now probably means the reservoir will be low at the end of growing season, both Britton and Gorman said. Although late spring and summertime rains could buoy the water level at Wickiup, the snowpack is not expected to help much.

Two automated snow measuring sites out of 14 in the combined Deschutes and Crooked River basins had snow at them as of Tuesday, said Melissa Webb, a snow hydrologist with the Natural Resources Conservation Service in Portland. Both were at record lows.

The low snowpack now means a low stream-flow forecast for the summer. She said the Deschutes River, aided by groundwater, probably will be about 70 percent of normal this summer upstream of Bend whereas the Crooked River upstream of Prineville Reservoir is expected to be 8 percent of normal.

“Everything across the state is quite a bit lower than normal summer stream flow,” Webb said.

— Reporter: 541-617-7812,

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