Bend Bulletin - Arnold Irrigation District conservation projects close to approval, district manager says

This article was published on: 08/7/22 3:54 PM

Federal funds to help pay for nearly 12 miles of canal to pipe conversion, wood flume taken off chopping block

On Bend’s southern outskirts, canals and ditches are already dry due to extreme drought conditions this summer, forcing farmers to reduce their herd size or give up their farms altogether.

But a conservation strategy by Arnold Irrigation District, which has supplied water to the area for 117 years, could extend the life of the irrigation season as soon as next year.

Steve Johnson, general manager for the district, said approval for the district’s Watershed Plan Environmental Assessment could be finalized by September or October. That approval will pave the way for a multi-million dollar funding package to get the piping project started as early as November.

It’s a multi-step process before approval can be given, said Johnson.

First comes the issuance of a finding of no significant Impact by the Natural Resources Conservation Service, a significant procedural step that is expected Monday. Then the watershed plan is sent to the agency in Washington, D.C., for authorization.

Piping the district’s antiquated canals would provide massive water savings for the district, which had to shut off water to patrons on July 23, the earliest shut-off date in district history, dating back to 1905. Had the canals been piped by now, water would continue to flow into September, said Johnson.

“It would be a dramatic improvement for Arnold,” said Johnson. “It’s the third year in a row that Arnold has had to turn off early.”

The district’s plan will convert 11.9 miles of its canal by installing a four-foot diameter pipe in four phases.

Phase one sees three miles of pipe converted over the coming winter and ready for use by March 2023. The remaining eight miles of the canal can be piped by 2026 or 2028.

Replacing the leaky, porous canal will conserve 11.2 cubic feet of water per second in the first phase alone, said Johnson. The entire project will save 32.5 cubic feet of water per second.

Getting back to a normal water allotment will help ranchers who rely on the water to grow hay for their livestock. When water is not available they have to cut the size of their herds or buy hay from other farms. Skyrocketing prices for hay are making this less feasible each year. The price for a ton of hay has reached $450 this year, compared to $300 a year ago.

Some Arnold patrons have gotten creative with their business.

Courtney Schuur, owner of the North 44 Farm in Bend, said she and her husband have no choice but to transfer their livestock to pastures in other irrigation districts when Arnold’s water runs out.

“It’s extremely challenging,” said Schuur. “When the water shuts off, we move all animals off-property into irrigation districts that have more senior water rights.”

The water savings has environmental benefits as well, said Johnson. Once piping is complete the district can divert 30% less water but still deliver the same amount of water to patrons. This leaves more water in the river for threatened species, including the Oregon spotted frog and bull trout.

“If the main canal had been piped last year, we would not have had to shut off at all, and the numbers would be similar for this year with slightly lower than average deliveries to the patrons’ head gates,” said Johnson.

Arnold’s piping plan does look a little different than it did a year ago. The district had to eliminate a fifth phase that would have seen the removal of a 70-year-old wooden flume that funnels water for more than a mile from the Deschutes River.

Without the flume removal, the cost of the project has dropped from around $42 million to $34 million.

Seventy-five percent of that total cost, or $24 million, will come from the federally funded Watershed Protection and Flood Prevention Act, also known simply as PL 83-566. The district has to match the remaining 25%, or $8 million, with non-federal funds.

Johnson said replacing the flume lacked the necessary cost-benefit ratio to receive the PL 83-566 funds. That’s because even though the flume is old and requires maintenance, it does not leak water as the porous canals do. Because the flume efficiently conveys water with little loss — and carries a high cost for replacement — the federal government determined it was not eligible to be included in the modernization project.

Adding the cost of the flume would also have made the funding request too high — PL 83-566 funding caps out at $25 million, so the irrigation district would have had to foot the bill for replacing the flume.

Johnson is hopeful for another round of funding that can replace the aging flume but doesn’t expect that to occur for another decade, at least. But he’s sure that the flume’s days are numbered.

“The point of replacing the flume is due to its age, the risk of structural failure, and increasingly high cost of maintenance,” he said. “It’s all about the capability and surety of transporting the water diverted from the Deschutes to our main canal.”

Until there is money to replace the flume, the district is committed to maintaining it and improving its efficiency. Johnson said a sealant will be placed on the galvanized steel plates that make up the flume to increase its longevity and durability.

“We will extend the life of that flume as much as possible,” said Johnson. “We feel really good about that sealant. It held up really well (in testing).”

Extending the life of the flume is also favored by some area residents who have grown to appreciate the picturesque wooden structure nestled in the Deschutes National Forest. Looking like a prop from an Old West film or a Loggers Run amusement park ride, the flume rises above the forest floor, cradled by the wooden scaffolding.

“I’m pleased that AID has decided not to proceed at this time with their original plan to replace the flume,” said Deschutes River Woods resident Alan Keyes. “AID’s original plan would have caused massive and permanent harm to the environment in this area.”

Keyes said when it comes time to deal with the flume he hopes that the wooden parts of the system can be replaced with steel supports “that mimic the design, color, and footprint of the existing wood, and which do not alter the existing landscape.”

-Michael Kohn