Removal of Dillon Dam could happen next summer
ECHO, Ore. — A headache for farmers and fish on the lower Umatilla River for decades, the Dillon Dam is finally near its end.
The Umatilla Basin Watershed Council and Confederated Tribes of the Umatilla Indian Reservation plan to remove the troublesome diversion dam near Echo by next summer. Not only has the concrete structure long blocked passage for native salmon, steelhead and lamprey, it has been a maintenance nightmare as gravel bars routinely wash over the irrigation headgate.
But before the dam can come out, water rights for the local Dillon Irrigation Co. need to be rerouted from another source. The watershed council came up with a design in 2014 that taps into the neighboring Westland Irrigation Canal, running 11,000 feet of pipe down Andrews Road and back into the Dillon Irrigation Ditch — completely bypassing the dam.
Funding for the project appears to be in place after the Oregon Department of Fish and Wildlife’s Restoration and Enhancement Board approved a $175,500 grant in May. The Oregon Fish and Wildlife Commission still needs to approve the grant at its Aug. 5 meeting in Salem, but Jon Staldine, executive director for the watershed council, said their proposal has been well-received.
“They saw it was really a collaborative project,” Staldine said.
The watershed council had already received $350,000 from the Oregon Watershed Enhancement Board and $20,000 from the CTUIR to build the pipeline. Staldine said the grant from ODFW will allow them to start construction in November or December, wrapping up by February so farmers can get back to work.
“The pipeline is the key project,” he said. “If that doesn’t happen, the dam won’t be removed.”
Dillon Dam is operated by the Dillon Irrigation Co., which was established in 1897. The company is currently made up of three landowners with approximately 1,400 total acres. Mike Taylor owns the Double M Ranch, the largest of the bunch, and also serves as president of the irrigation company.
Taylor has been talking about getting rid of the Dillon Dam for 15 years before the watershed council took the reins. He said the Dillon Irrigation Co. collects $10 per acre from landowners, most of which goes toward paying for maintenance at the dam.
Whenever high flows sweep down the river, it washes gravel and debris that plugs up the headgate and fish ladders at the dam. It’s up to the producers to come in and clean up the mess. Taylor said they’re looking forward to having a more reliable water delivery system from the Westland Canal.
“Getting the dam out of the river is a good thing,” Taylor said. “We’ve been working on it for a while.”
Once the pipeline is complete, the watershed council and tribes can turn their attention to physically removing the dam from the river. Staldine said they are working together on a design and applying for permits, which could take four to six months to be approved.
If all goes smoothly, in-stream construction will take place sometime between July 15 and Sept. 30 of next year. Staldine said they haven’t yet worked out the cost, but said it will be paid for out of the tribes’ Fish Accords with the Bonneville Power Administration.
Dillon Dam was originally built in 1915 and replaced sometime in the mid-1970s. It does have fish and lamprey ladders, though Staldine said they’re not up to current standards. Bill Duke, fish biologist with ODFW in Pendleton, said the dam has been a complete barrier to lamprey in past years, and a partial barrier to salmon.
“In some years, it’s a significant portion of the fall chinook run that gets delayed down there,” Duke said.
Staldine said the problem affects juveniles as well as adult fish stuck below the dam. The likelihood of survival for juveniles reared below the dam are virtually non-existent due to high water temperatures in the summertime, he said.
Yanking the dam will allow more fish, including fall and spring chinook runs, to make it to their traditional spawning grounds farther up the Umatilla River, boosting survival and providing more fishing opportunities.
“We won’t have fish caught below that are essentially getting fried every year,” Staldine said.