This article was published on: 11/27/07 12:00 AM
Low flows put Deschutes quality at risk
River disrupted to fill reservoirs for next season
By Jim Witty / The Bulletin
Published: November 27. 2007 5:00AM PST
If a river is all about the water, then not all is well on the Deschutes.
It’s suffering from seasonal disruption disorder. That was apparent during a recent stroll along the Upper Deschutes in La Pine State Park.
During the winter, it’s the Upper Deschutes that gets whacked. Beginning in late October, when irrigation season ends, it’s reservoir filling time. With Wickiup Reservoir about half full, flows on the roughly 25-mile reach between the dam and Bend go from an average of 1,000 cubic feet per second to 27 cfs, to allow the reservoir a chance to fill up for the next irrigation season.
During the summer months, with irrigation activity in full swing, the low water focus shifts to the Middle Deschutes downriver from the irrigation outlets in Bend. That’s when the flow is low (about 7 percent of natural, historic flows) and what water there is feels tepid to the touch, marginal conditions for the lethargic rainbow and brown trout that a few months earlier flashed with native vigor.
The problem, according to Bea Armstrong of the Deschutes River Conservancy, is not simple.
Every year in the spring, the irrigation canals are opened and the Deschutes River between Bend and Lake Billy Chinook drops significantly.
According to Tod Heisler, executive director of the Deschutes River Conservancy, the lower flows instituted by North Unit Irrigation District lower the overall health of the river, degrade fish habitat and contribute to higher water temperatures and a general diminution of water quality.
“One of the big problems is sedimentation loads,” Heisler explained. “The up and down action increases the sedimentation problem.” Suspended sediment in the water lowers the quality.
“Low flows also wreak havoc on the vegetation, the riparian habitat,” Heisler noted, standing on a bluff above the river.
The field trip to the Upper Deschutes flowing through La Pine State Park revealed a river that’s a shadow of its summer self. It’s what anglers call “skinny water.” Vast sections of the river are now exposed. That concentrates fish into smaller areas and leaves rocks and other habitat-enhancing structure high and dry,
It’s one thing to read or hear about the low flows, another to see it firsthand. We were walking in the streambed where water recently flowed. Aquatic vegetation, its connection to the river severed, was drying out on the sand. Detritus — beer cans, part of a picnic table, downed trees — lay exposed well below the high water mark.
“It’s an amazing transformation,” said DRC program director Scott McCaulou.
The DRC is working to restore flows to the river, a little bit at a time. Formed in 1996 as an experiment in collaboration, the conservancy works with farmers, irrigation districts, anglers, power producers, the Confederated Tribes of Warm Springs and developers to restore some of the historic stream flow in the sprawling Deschutes watershed.
Balancing the needs and concerns of such a diverse conglomeration of river users can be complex, explained Kyle Gorman, regional manager of South-Central Oregon for the state Water Resources Department. Heisler agreed.
“The trick is to work with the agricultural community to come up with solutions to support their way of life and increase flows in the river,” said Heisler.
A recent project illustrates DRC’s methods.
The minimum allowable flow out of Wickiup, based on historic irrigation water rights, is 20.3 cfs. With flows on the upper Deschutes at about 27, the DRC recently entered into a lease agreement with the irrigation district in Lone Pine, northeast of Redmond, to put 10 cfs more flow into the river for 100 days, in exchange for about $30,000 worth of financial incentives for the irrigator from the DRC, a nonprofit organization that relies on fundraising. The irrigation agency makes the necessary conservation adjustments in exchange for money.
“They’re operating more efficiently — with a financial incentive — and the water goes back into the river,” said Heisler.
Bumping the flow by 10 CFS may not seem like much, based on historic levels, but going from 27 to 37 cfs represents a large percentage, Heisler noted. He said the leasing program has temporarily protected water flows in Whychus Creek, the Deschutes and Crooked rivers and their tributaries.
Also in the DRC quiver of water-conserving tools is a program that permanently transfers water rights back to the river. To date, the program has permanently protected more than 4 cfs of instream flow through the program.
The group also lines canals and supports piping projects (to counteract evaporation and seepage in canals) to conserve water in the river.
The DRC is also intimately involved in the effort to return steelhead and salmon to Whychus Creek and the rest of the Deschutes River watershed. All the while making sure the interests of farmers, developers, anglers, power producers and the tribes are protected. “It’s an intricate dance,” said Gorman.
Jim Witty can be reached at 617-7828 or jwitty@bendbulletin.com.