WALLOWA — The Wallowa mid-valley isn’t just home to stunning scenery — it contains some of the county’s best farmland. The Lostine and Wallowa rivers converge here, supplying irrigation water to maintain crops for export and local livestock feed. On the Lostine River alone, there are 11 ditches diverting its water to help support the county’s agriculture-based economy.
Since 1879, the Tulley-Hill irrigation ditch has diverted Lostine River water to mid-valley farms, according to Montana Pagano of the Nez Perce Tribe’s watershed division. Today, it supplies 119 acres with adjudicated water rights between May 1 and Sept. 30.
One hundred fifty years ago the Wallowa Band of the Nez Perce Tribe fished Wallowa County’s rivers for coho, chinook and sockeye salmon as well as steelhead. In the last 25 years, since chinook were added to the federal endangered species list, fisheries, including Nez Perce Tribal Fisheries, have worked closely with landowners to ensure crops and fish get the water they need.
In an effort to continue serving both crops and fish, a reconstruction of the Tulley-Hill ditch began in late July. Funded by the Bonneville Power Administration and Oregon Watershed Enhancement Board, the resulting restoration will improve anadromous fish passage to the Lostine River upstream of the diversion structure and fish ladder.
The new fish passage at the Tulley-Hill ditch diversion replaces structures installed by the U.S. Bureau of Reclamation in 1998. Over time those structures, Pagano said, caused scour pools to form in front of them, creating an upstream barrier. During late-summer low-water flows, juvenile and adult chinook migrating up the Lostine River to spawn faced an elevation greater than 12 inches, exceeding fish passage criteria for “jump height,” the height that a fish can jump over a barrier.
A Nez Perce Tribal Fisheries report outlining the project said there was a concern that as the existing structures continued to age, extreme high water could cause catastrophic failure at the diversion, endangering the continued survival of salmon and steelhead and a properly functioning irrigation ditch.
Pagano said the idea behind the design of the reconstruction, called a roughened channel, uses rocks instead of concrete. Before the rocks could be placed, fish within the project area were electro-shocked and moved. The ditch water was piped almost 280 feet and, during construction, the river was diverted to the ditch in the dewatered river channel.
In mid-August, Joe Partney of Partney Construction used an excavator to carefully placed large boulders in a V-shape, creating one of the project’s eight rock and log weirs. Joe Smetana stood nearby on a boulder with a transit “shooting the grade,” measuring the elevation of the rocks of the newly formed weir against the project’s design specifications.
Katie Frenyea, of Nez Perce Fisheries Watershed Division, said the new system mimics nature by using rocks as they would normally line a river, and the distance is now twice the length of the previously constructed fish passage creating a shallower incline.
“The weirs have enough grade for the farmers to get irrigation water while still passable for fish,” Frenyea said.
She explained that because the stretch of river lacked pools, several small ones were designed throughout the project area with a large plunge pool at the lowest end.
The project was designed to fully allow farm operations to continue without interruption. Pagano said it was important the design not interfere with the use of the diversion’s head gate that controls water flowing from the river into a canal. She said the design also had to take into consideration the logistics of the project area, which is confined by a road on one side and the toe of a hill’s slope on the other.
This fall, staff from the tribe and the Grande Ronde Model Watershed will help contractors plant the streambank to control erosion, Frenyea said. As the willows and osiers grow taller they will create shade that will help cool the water’s temperature.
As in similar projects completed in 2012 and 2016 on the Lostine River, construction of the Tulley-Hill project was staged on private property. Coby Menton of the Grande Ronde Model Watershed worked with the Nez Perce Tribe’s watershed division overseeing the project. He emphasized the importance of the farmers’ cooperation.
“The landowners’ most valuable contribution is granting permission,” Menton said.
On site it was easy to see why the landowners’ permission was so crucial — portions of two farms, one owned by Woody Wolfe and one by Perry Johnston, were transformed into a construction zone for more than a month.
Wolfe has long worked with the Nez Perce Tribe. Its fisheries division operates its Lostine weir on his ranch upriver from the confluence of the Lostine and Wallowa. The tribe uses the weir for research and broodstock collection for fish hatcheries. This summer, the tribe contributed a percentage of the purchase price of a conservation easement between Wolfe and the Wallowa Land Trust.
“Allowing (the construction) to be here is creating good things,” Wolfe said.