This article was published on: 04/5/19 12:00 AM
Arnold Irrigation District looks to pipe more than 30 miles of canals
By Stephen Hamway
Central Oregon residents will have a chance to weigh in later this month on a massive project to pipe canals to the south of Bend.
The Bend-based Arnold Irrigation District will hold a public meeting at Elk Meadow Elementary on April 17 as part of its proposal to replace its system of aging, open-air canals with enclosed, high-density polyethylene pipe. If the small irrigation district is able to replace its entire network of canals, the district estimates that it will be able to conserve more than 45 cubic feet of water per second, enough to flood more than 14,600 acres with a foot of water over an irrigation season.
“It just sounds like a good deal, and it’s probably something the district needs to do just out of social responsibility,” said Shawn Gerdes, manager and board secretary of Arnold Irrigation District.
Arnold Irrigation District maintains a network of 39 miles of canals and pipes, which it uses to provide about 640 customers with water diverted from the Deschutes River around Little Lava Island during irrigation season. Gerdes said the district has piped about 7.5 miles of the system, primarily in areas where subdivisions have gone in.
The remainder of the system, however, relies on open-air canals that were built about 1900, Gerdes said.
Like similar systems in Central Oregon, the canals lose a significant amount of water to evaporation and seepage. Making matters worse, Gerdes said much of the network was built in areas with lava rock, and water can seep into the porous rock more easily than in other parts of Central Oregon.
Consequently, the irrigation district loses just under half the water it diverts from the river before it reaches the district’s customers, Gerdes said. By replacing the canals with pipe, the district can divert less water while still delivering just as much to customers.
“It’s a way that we can actually put quite a bit of water back in the river,” Gerdes said.
Arnold Irrigation District is one of several irrigation districts operating in the Deschutes Basins that have kicked off ambitious piping projects in recent years, thanks to a growing network of grants and other funding mechanisms.
Last fall, Sen. Jeff Merkley, D-Ore., spearheaded an effort through the Senate Appropriations Subcommittee on Agriculture to secure $30 million that could go toward piping Tumalo Irrigation District canals. Three Sisters Irrigation District has replaced more than 90% of its canals with enclosed pipe.
Margi Hoffmann, community relations director for Farmers Conservation Alliance, which works with irrigation districts to help secure state and federal funding, said Swalley Irrigation District recently had its plan to replace its system approved by the National Resources Conservation Service.
Hoffmann estimated that piping the system will cost $48 million. Because of that, Gerdes said securing outside funding is critical to getting a piping project going for a small district like Arnold.
“We really haven’t done any big piping projects at all,” Gerdes said. “This is all brand-new ground for us.”
To apply for federal funding through the NRCS Watershed Protection and Flood Prevention Program, Hoffmann said districts must submit a plan and go through a robust public process. During the meeting on April 17, residents will have the chance to learn about the project and weigh in on which parts of the system should be piped first. Public comments on the project will be accepted until May 15.
“This is really the first step,” Hoffmann said.
Gerdes said the piping project likely won’t break ground until 2021 at the earliest, and will likely focus on the district’s main canal before moving onto the secondary canals. While he acknowledged he didn’t quite know what to expect at the meeting, he said he was hopeful the community would understand the need.
“If you get the community and everybody else behind (the project), it can happen faster,” Gerdes said.
— Reporter: 541-617-7818, shamway@bendbulletin.com