From above, the main channel of the Arnold Irrigation District appears like a serpent, winding in gentle green curves along the southern fringe of Bend. At ground level, the canal is lined with shrubs and ponderosa pines, perfect cover for mule deer and other wildlife. It sounds idyllic.
But just underground is a highly prized water supply that is the subject of fierce debate.
The water supply that feeds this ecosystem is the result of water seeping into the ground from the canal, which was installed over a century ago by settlers who could not foresee the problems, the debates and the environmental impact their irrigation projects would cause on future generations of Bend. residents.
Arnold Irrigation District wants to stop seepage with a $34 million pipeline. The piping, according to the district, could have maintained irrigation water until September of this year. Instead, the district ran out of water a month ago, leaving the canal dry.
But people living near the canal — mostly residents of Deschutes River Woods and Woodside Ranch — are fighting the canalization plan to hold back some seepage. Save Arnold Canal, a grassroots community-led movement, believes seepage will keep the ground saturated during the months when water is available. Infiltration is necessary to protect the micro-habitat that runs along the canal, they say.
Save Arnold Canal has a website to promote alternatives to piping and a lawyer as well. Instead of a pipe, the group wants the channel to be lined with semi-permeable concrete to retain most of the water, but also allow around 30% to seep into the ground to charge the aquifer shortly. deep.
“Everyone wants to conserve water for the good of the Deschutes River. But what will be lost when Arnold Irrigation channels its main channel? Twelve miles of animal habitat, thousands of mature ponderosa pines and dozens of working wells,” said Geoff Reynolds, a supporter of the group.
Alan Keyes, another resident of the area, is mostly worried about the fate of mule deer and other wildlife that inhabit his neighborhood. Cutting off the water flow will permanently disrupt local habitat and drive animals away, he said.
“Wildlife shares our unique environment and contributes to its character,” Keyes said. “Drive them out and you will further erode the uniqueness of our region.”
Compromise solution sought
Mark Elling, president and board member of Save Arnold Canal, says locals are concerned about property values, community aesthetics and the local ecosystem. But he adds that an open channel instead of a pipe provides benefits throughout the Deschutes Basin, including wildlife habitat, accessible water for fighting wildfires and groundwater.
“We believe that for the benefit of all, whether it is keeping water in the reservoir for winter endangered species habitat or transferring water to Madras North Unit, we believe that there are other ways to do this that don’t have the collateral damage of the pipeline,” said Elling, whose property backs onto the canal.
Elling wants the Arnold Irrigation District to consider lining the canal walls with shotcrete, a form of concrete, instead of enclosing the canal in high-density polyethylene pipe. According to him, the shotcrete will be cheaper than the piping, even if it has to be replaced.
A channel lined with shotcrete can also be made permeable to allow some of the water to seep into the ground, but also retain more water than the current channel, which is mostly unlined.
“Our group advocates the most commonly applied style of non-membrane shotcrete in a layer of at least three inches,” Elling said. “By avoiding the membrane, there is still a certain amount of infiltration to damage trees and wells less, and it’s much cheaper without the membrane.”
The geomembrane mentioned by Elling is essentially a giant sheet of plastic used as a waterproof barrier that can be installed under a layer of shotcrete. This would reduce leakage into the ground to small amounts – which is good for water conservation – but would fall short of the Save Arnold Canal Group’s goal of allowing 30% seepage to sustain the ecosystem at the edge of the canal.
Steve Johnson, district manager for the Arnold Irrigation District, says simply lining the channel bed with shotcrete, with or without a membrane, would require more maintenance than the piped option. Funds for repairs are not guaranteed, he said. Piping saves 100% of water from seepage and evaporation, he said.
As for the green aesthetic the seep provides, Johnson notes that for much of the year, the idyllic creek flowing behind people’s homes is non-existent. Certainly, during the last three years of drought, the district has had to turn off the water on record dates.
“Their water feature only has water for three and a half months, and it’s empty for eight and a half months,” Johnson said. “How attractive is this ditch for eight and a half months of the year when there is no water in it?
While farmers will benefit from the proposed hose and more water later in the irrigation season, conservationists and conservationists say they are happy with the expected benefits for the Deschutes and aquatic species trying to survive in the diminished river. Energy consumption will also be reduced as the pressurized pipe eliminates the need for pumps.
The piping project has support from the Coalition for the Deschutes, Central Oregon LandWatch, and the Deschutes River Conservancy, at least compared to the liner options that require more maintenance and less water conservation.
Up to 10,446 acre-feet of water could be available during the winter months if the pipeline project goes ahead. An acre-foot is the amount of water that can fill an acre of land with one foot of water. This will be accomplished through an exchange with the North Unit Irrigation District and will also provide North Unit farmers with more water during the irrigation season.
The support of biologists and ecologists for the channeling is not surprising given the tendency of local environmental associations to support projects that raise the level of local rivers at all costs.
The Oregon Department of Fish and Wildlife says piping is safer for wildlife. Rather than a safe corridor, canals are considered a hazard that can trap deer in both winter and summer, especially if the canal is lined with concrete. As for the argument that the canals provide drinking water, ODFW field biologist Andrew Walch said mule deer and other animals would simply find water elsewhere.
“There are usually irrigated fields, ponds and yards nearby that provide water sources,” Walch said. “It may just change the distribution and patterns of wildlife that people are used to seeing on their property.”
US Fish & Wildlife also has clear motives for supporting the piping plan. The agency is responsible for protecting endangered species such as the Oregon spotted frog and bull trout. Canal closures support goals outlined in the Deschutes Basin Habitat Conservation Plan, approved by U.S. Fish & Wildlife in 2020. By failing to adhere to the conservation plan, irrigation districts risk losing their permits of “by-catch” that allows them to operate for the life of the 30-year agreement.
For area residents, the pipe’s purported benefits to rivers provide chilly comfort when their community is on the brink of dramatic change. Their grievances echo complaints filed by several Tumalo Irrigation bosses, who filed a lawsuit in 2020 over the impacts a pipeline project has caused in their community. This costume could portend what might happen to Arnold.
Brian Sheets, the agriculture and water rights lawyer who represents the Save Arnold Canal group, says the group is open to discussing a variety of water conservation options, but plumbing is not one of them due to “environmental considerations” and impacts on local ecosystems.
“The piping will evacuate the water from quite a few trees. It will take water from well recharges. This will take water from the riparian habitat that runs through the area,” said Sheets, who is based in Ontario, Oregon. “We don’t think Arnold Irrigation District has considered all the different alternatives that can be used to mitigate their losses and have a win-win situation for everyone.”
Deschutes County Forester Ed Keith — who serves as a liaison between federal, state and local agencies to manage forests and prevent fires — agrees with the Save Arnold Canal group that tree loss will likely occur.
But Keith, the county forester since 2012, says trees along the canal are growing to unsustainable levels. If they can survive without water from the canals, they will, he said.
“Otherwise they shouldn’t be there to begin with. We live in a desert,” Keith said.
Instead of maintaining the artificial environment of the canal, Keith said the priority should be to minimize impacts to fish and wildlife in the Deschutes.
He described a host of frequently cited negative impacts, including unusually high flows in summer, unusually low flows in winter, increased sedimentation and the resulting negative impacts on fish habitat and water quality. .
“The Cadillac desert can’t go on forever,” Keith said, referring to Marc Reisner’s 1986 book, which chronicles the history of irrigation in the arid regions of the American West.
Keith also threw cold water on the idea that the seasonal waterway should be preserved for the sake of the trees that grow beyond their natural range.
“It seems to me that these people expect personal benefits from the canals that run through their properties by expecting them to continue to operate with a design that is over a century old, at no cost to them, and with a significant negative cost to public resources,” Keith said. “These include water, fish and wildlife, and agricultural land that depends on efficient water supplies.
Save Arnold Canal may not have garnered widespread support from Bend’s environmental groups and agencies, but that hasn’t stopped its supporters from backing down.
Keyes, one of the neighborhood residents, concludes that the district is simply not listening to what the locals have to say. He calls the district’s plan “short-sighted” and in complete disregard for the long-term impact on his community.
“If the AID piping proceeds as proposed, Bend area residents, visitors and future generations will look around and wonder what happened to the Bend we loved?” said Keyes. “But by then it will be too late.”