A small irrigation district's big idea for taking over Mirror Pond dam

April 25, 2015
A small irrigation district's big idea for taking over Mirror Pond dam

Tumalo Irrigation District’s idea for the dam could improve the health of lower Tumalo Creek and the Middle Deschutes River

By Scott Hammers / The Bulletin

If the Tumalo Irrigation District can strike a deal to take over the Mirror Pond dam, the biggest impact may not be felt in the placid waters alongside Bend’s Drake Park, but a few miles away near where Tumalo Creek meets the Deschutes River.

At a meeting of the Mirror Pond Ad Hoc Committee on Thursday, Bend City Councilor Victor Chudowsky said the most exciting prospect presented by the district’s pitch is the possibility it could scale back the use of its Tumalo Creek intake, adding dramatically more cold creek water to the Deschutes River system. Doing so would improve the health of lower stretches of Tumalo Creek and the Middle Deschutes River, “beyond the wildest dreams of anyone,” Chudowsky said.

Ken Rieck, manager of the Tumalo Irrigation District, said Thursday the district’s hope would be to rehabilitate the more than 100-year-old dam on Mirror Pond owned by PacifiCorp and use it to generate electricity and provide an income to the district.

An irrigation intake at the Steidl Dam a short distance downstream would be retired, Rieck said, and replaced with an intake at the Mirror Pond dam that could draw in more water at higher pressure to feed the district’s pipe wrapping around the north side of Awbrey Butte. The improved intake, if combined with additional water rights to Deschutes River water, would allow the district to draw less water at its other intake just below Shevlin Park on Tumalo Creek.

Rieck said his district has several goals with its proposal, but restoring water to the area below its Tumalo Creek intake ranks high among them.

Rieck said even if his district and other irrigation districts significantly reduced the amount of water they pull out of the Deschutes River, the health of the stretch known as the Middle Deschutes — running from Bend to Lake Billy Chinook — depends on an infusion of water from short, fast-moving and glacier-fed Tumalo Creek.

“What’s good for trout is cold water,” Rieck said. “If we’ve got X amount of water going past all the irrigation diversions in Bend, and if we were to add more water to that in the Deschutes River, we’ll not make it better water — because it doesn’t change in temperature.”

By the time they reach the Bend area, Tumalo Creek runs about 10 degrees cooler than Deschutes River, Rieck said. The more Tumalo Creek water is available when the creek meets the river, the cooler — and better for fish — the water will be from there downstream.

Boosting flows in the lower stretches of Tumalo Creek and dropping water temperatures could also address many of the concerns raised in a lawsuit filed against the city by Central Oregon LandWatch, a local environmental group opposed to aspects of the city’s surface water intake project. The project draws water for city use from a pipe at Bridge Creek, a tributary of Tumalo Creek more than 10 miles upstream from the Tumalo Irrigation District’s Tumalo Creek intake.

The suit asserts that the city’s use of Bridge Creek water leaves too little in Tumalo Creek for fish and other wildlife, particularly below the irrigation district’s intake.

Bend City Manager Eric King said the suit has been appealed to the 9th U.S. Circuit Court of Appeals, after a U.S. District Court judge ruled for the city and against LandWatch late last year. King said the two sides intend to enter mediation next month but was uncertain whether the Tumalo Irrigation District’s proposal would factor in to how it might help the two sides resolve their differences.

Chudowsky said even before Tumalo Irrigation District put its proposal on the table, the district’s push to pipe the canals and laterals it uses to serve the Tumalo area have allowed it to return more water to Tumalo Creek, satisfying many of the concerns raised by the lawsuit.

“All these developments with (the irrigation district) piping are completely passing LandWatch by,” Chudowsky said. “They have not been a part of this process whatsoever; we’ve been urging them to be involved, to have a seat at the table and help us out, and so far, they haven’t done so.”

Paul Dewey, executive director of LandWatch, said even if the district were to restore water to lower Tumalo Creek, it wouldn’t address his group’s concern that the city’s diversion leaves too little water in the creek further upstream. Still, he said, he’s liked what he’s heard of the irrigation district’s proposal so far and felt it could help bring LandWatch and the city to an agreement.

“We’re very interested; it’s an intriguing concept,” Dewey said Friday. “Of course we don’t want just another piping project or hydro project where conservation is only a possibility 10 or 20 years down the road.”

For the Tumalo Irrigation District to rely less on Tumalo Creek water and more on Deschutes River water, it would need to secure additional water rights beyond its current Deschutes River allotment.

Any decision on water rights would have to go through the Oregon Department of Water Resources. Kyle Gorman, regional manager for the department, said from what little he’s seen, the irrigation district’s plan appears to be achievable.

Gorman said as of today, the Tumalo Irrigation District has water rights allowing it to draw up to 140 cubic feet per second from the Deschutes River, and 200 cfs from Tumalo Creek. However, it doesn’t take that full amount from either source, Gorman said, usually topping out at around 180 cfs during the height of summer.

The district would have a few options if it wanted to meet customer demands while using less water from Tumalo Creek, Gorman said.

Gorman said the district could buy water rights from a user served by a different irrigation district, an opportunity that presents itself when a farm or other irrigated property is redeveloped for more urban-style use. Alternatively, it could continue piping its canals and laterals to boost efficiency within its own system. Though the district draws up to 180 cfs from the creek and the river today, Gorman said much of that never makes it to farmers’ fields and is instead lost to evaporation and seepage out the bottom of unlined canals.

A conservation project by one of the other irrigation districts that takes water from the Deschutes could be another opportunity, Gorman said. Current law only requires 25 percent of water saved through conservation to go back in to the river, he said — if another irrigation district on the Deschutes piped its canals or found other ways to save 100 cfs, 75 cfs could be sold or otherwise transferred to the Tumalo Irrigation District.

Gorman said there are still many steps the district would have to take before it’s known if its proposal can work.

“You never know what could pop up; you never know what environmental hurdle could pop up that they couldn’t get over,” he said.

Representatives of the city of Bend and the Bend Park & Recreation District are looking to arrange a meeting with the Tumalo Irrigation District to learn more about the proposal, but for now the utility company that owns the Mirror Pond dam has not been in contact with the irrigation district.

PacifiCorp representatives would be interested in learning more about the irrigation district’s plan to acquire its dam, Bob Gravely, PacifiCorp spokesman, said Friday.

“If this is a proposal they’re serious about, and local officials are taking seriously, we’d certainly expect those conversations to take place,” Gravely said. “But nothing’s happened, yet.”

— Reporter: 541-383-0387,


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