$10 million project improves fish habit
Two open irrigation ditches, operated by Barkley Irrigation Company and Methow Valley Irrigation District (MVID), have been completely enclosed in pipe through a project that broke ground almost three years ago.
Since the early 1900s, Barkley and MVID have provided irrigation on the east side of the Methow River north of Twisp. Like other previously open ditches in the Methow Valley, including the Skyline and other portions of MVID, the Barkley and the last open section of MVID are now piped to improve fish habitat by reducing the amount of water diverted from rivers.
Plans to transform Barkley’s 8-mile-long open canal to a pipeline system began almost 10 years ago, after the irrigation company was told by federal fisheries officials that it needed to change the way it diverts water from the Methow River.
The $10 million construction project, led by Trout Unlimited, is being completed this summer, said project manager Aaron Penvose.
“We got started in late fall of 2018 … and just wrapped up the final major construction phase this spring in May,” Penvose said. “The Barkley has now joined the 21st century. It is a big deal and a major upgrade.”
“The historic canals and ditches were put in during the early 1900s; the infrastructure that allowed that to happen is ancient and in disrepair,” Penvose said. “Making water move more efficiently” has become more critical with the impacts of climate change, he said.
As a result of the changes to the irrigation systems, more water will remain in the Methow River to support fish. “And Barkley and MVID have new infrastructure for the next century,” Penvose said.
Work was completed in several phases over the past three years to allow water to continue being delivered during irrigation season, Penvose said. One of the most visible signs of the changes is removal of cottonwood trees that thrived along the open ditch that flowed next to the Twisp-Winthrop Eastside County Road.
Impetus for change
The impetus to develop a new irrigation system for the Barkley ditch came in 2012 when federal fisheries officials told the Barkley Irrigation Company to end its longstanding practice of creating a temporary dam. Each July, as the Methow River began to approach summer low flows, the company, under a permit from the state, would drive a bulldozer up a side channel of the river to create an earthen dam to direct water toward the ditch.
The temporary dam channeled water from the mainstream of the Methow River into a side channel leading to the Barkley headgate, adversely impacting fish habitat, Penvose said.
The canal headgate was located about a half-mile upstream from the confluence of Bear Creek and the Methow River. Because the first half-mile of the canal did not have a fish screen, endangered fish species — including juvenile spring Chinook, steelhead, bull trout and Pacific Lamprey — would become stranded when the ditch was shut down, and had to be removed by hand.
Trout Unlimited and numerous other partners worked with the irrigation company to develop a plan to address those issues and reduce the amount of water taken out of the river.
The new Barkley irrigation system combines gravity-fed and pressurized piped systems to serve Barkley water users. The point of diversion from the Methow River was moved 4 miles downstream from the original headgate and consolidated with an MVID diversion near the south end of the Methow Valley State Airport.
Improving fish habitat
Moving the Barkley diversion downstream improves instream flow in those 4 miles of the Methow River by 26 cubic feet per second (cfs), Penvose said. And Bear Creek, which previously dumped water into the Barkley canal, will be reconnected to the Methow River through a restoration project by Methow Salmon Recovery Foundation, providing access to habitat suitable for steelhead spawning and rearing, he said.
Water for MVID and Barkley is carried from the diversion near the airport in two buried pipes that run parallel to each other downhill to Mill Hill, located across the river from the Twisp Park. The water for Barkley and MVID previously converged in an open ditch about 2 miles above Mill Hill.
The rest of MVID’s open canal system along the east and west side of the Methow River was enclosed in a project that was completed in 2016. Barkley serves about 40 shareholders, and MVID has approximately 240 members.
The easement for the new buried pipelines along the Twisp-Winthrop Eastside County Road, previously an open ditch, is now a smooth flat surface, which has proved to be an attraction to bikers and walkers, Penvose said. However, the easement is on private property and not open to the public for recreation, he said.
In addition to the piping, a pump station was installed at the new Barkley headgate near the airport to feed a smaller pipeline that pushes water to irrigators with property above the grade of the new pipeline.
“Creating a pressure system generates the most water savings,” Penvose said. It provides an “on-demand” service, in which water is only transported when needed by irrigators, rather than being carried in an open ditch throughout the irrigation season.
At the upper end of the Barkley ditch, upstream of the airport, six ditch customers were provided wells, “eliminating 1.5 miles of leaky earthen canal and the need for a lengthy pipe installation with few services,” Penvose said. With those customers served by wells, “a large portion of the upper Barkley was abandoned,” he said.
The project was initially estimated to cost about $5 million. But consolidating the diversion for the two ditches and piping the upper four miles of MVID, coupled with higher construction and material costs — especially for 40,000 feet of pipe — pushed the project budget just over $10 million, Penvose said.
Funding for the project comes from the Bureau of Reclamation, Bonneville Power Administration, Confederated Tribes of the Colville Nation, Chelan and Douglas County Public Utility Districts, Natural Resource Conservation Service, National Fish and Wildlife Foundation, Priest Rapids Coordinating Committee, Department of Ecology, Washington State Conservation Commission, U.S Forest Service, Okanogan Conservation District, Methow Conservancy, U.S. Fish and Wildlife Service, Salmon Recovery Funding Board and Trout Unlimited.
The redesign of the irrigation system offered opportunities for habitat restoration, including a project undertaken by the Methow Salmon Recovery Foundation (MSRF). The two-year project, which began last year and continues this year, “will restore ecological processes at the historic location of the Barkley Irrigation Company diversion to improve fish habitat for steelhead and spring Chinook,” according to MSRF.
The project will repurpose and enhance the irrigation features no longer needed by the Barkley irrigation company to improve floodplain connectivity, MSRF said.
Specific actions include creating a new inlet to the existing side channel, removing the existing head gate and converting portions of the irrigation canal into side channel habitat. The project will also remove riprap protecting the irrigation canal and reconnect Bear Creek with the Methow River.
Engineered logjams and other wood placements within Methow River, connected side channels, and the floodplain will increase habitat for the endangered salmon, according to MSRF. Work within the Methow River is limited to the month of July in each year to protect fish species.
Work began this year in late June and will continue along the left bank of the Methow River through July.