Fish return sparks excitement
The release of a three-year water quality study and salmon returns in the Deschutes River were big news for Portland General Electric over the past week.
Across the Columbia River basin, disappointing returns of spring Chinook salmon are the norm this year, including returns at the adult fish trap just below the Pelton Round Butte Hydroelectric Project, near Madras, which are the lowest in years.
But there's a twist: Despite the poor returns, biologists at the Pelton trap report this is shaping up as one of the best years so far for returns of reintroduced spring Chinook that originated in Deschutes River basin above the hydro project.
"This is exciting," said Megan Hill, the Portland General Electric biologist who leads the fisheries and water quality team at the hydro project. "With the odds stacked against the fish this year due to ocean and river conditions outside the basin, the fact we're seeing relatively strong upper basin returns is likely directly related to improvements we made in juvenile downstream fish passage two years ago."
PGE and their co-owner at the hydro project, the Confederated Tribes of Warm Springs, are working with dozens of partner organizations and agencies in the Deschutes Basin to reintroduce salmon and steelhead runs that were cut off when Pelton and Round Butte dams were built in the 1950s and '60s.
Given the long lifecycle of these migratory fish, it can take from two to four years for changes made to help the fish to show results. It's a long-term project and runs cannot be expected to be self-sustaining for decades to come.
While more than a million juvenile fish have successfully passed downstream since PGE and the tribes completed a new fish passage system at the dams in 2010, adult returns have been slower to recover than initially hoped, with a combined annual total ranging from 72 to 620 Chinook, sockeye and steelhead. The strongest individual run occurred in 2016, when 536 upper basin sockeye returned to the project.
Two years ago, dam operators made changes to improve smolt survival by collecting and releasing juvenile fish at night, when the fish are most active and less vulnerable to predators.
Last year, just five upper basin spring Chinook made it home, but this year, a total of 46 have completed the trip so far and have been released to spawn in the Deschutes tributaries above the dams. That occurred even though the total return of spring Chinook — including fish that originated at the Round Butte Fish Hatchery — is less than a third the size of last year's total return.
Of the 46 upstream fish that have returned, five have made their way up Whychus Creek, near Sisters, where they have been tracked to locations in restored salmon habitat along the creek that is protected by the Deschutes Land Trust at Willow Springs Preserve and Rimrock Ranch and, just above and below the Land Trust's Camp Polk Meadow Preserve.
That is the largest number of adult fish that have returned to Whychus Creek in any year of the restoration effort so far.
"The Land Trust is thrilled to have the first Chinook make it back to our Willow Springs Preserve! We've worked for more than 20 years to ensure the lands and waters of Whychus Creek are protected so native fish like Chinook will always have a place to come home," said Brad Chalfant, executive director of the Deschutes Land Trust.
"It's heartening to see that our collaborative efforts with PGE, the Confederated Tribes of Warm Springs, the Deschutes River Conservancy, and the Upper Deschutes Watershed Council are helping protect and improve habitat and water quality for native fish," he said.
More information and regular updates on the work of restoring salmon and steelhead runs on the Deschutes is available at www.portlandgeneral.com/deschutes.
After three years of data collection at nearly 30 sites, months of analysis and complex modeling, and several weeks of review by an independent technical team, PGE and the Confederated Tribes of Warm Springs released a major Deschutes River water quality study late last week.
The report is the first of its scale, examining more than 20 water quality parameters over the course of several years, from the tributaries entering Lake Billy Chinook all the way to the mouth of the river where it enters the Columbia.
The study is an important addition to the body of scientific data on the Deschutes, so water quality and fisheries managers are hopeful that it will help them in their continued efforts to make balanced, informed decisions for the river.
PGE and the tribes commissioned the study back in 2015, to gain a better understanding of water quality conditions in the Lower Deschutes River.
"We realized that, while we had extensive information on fish passage and other components of the ecosystem, we had this critical gap in our dataset," said Hill, the PGE biologist who leads the fisheries and water quality team at Pelton Round Butte. "We're excited about using this study to move forward with our collaborative work in the Deschutes Basin."
The co-owners shared the report on June 20, with the Pelton Round Butte Fish Committee — a group of representatives from environmental nonprofits and state, federal and tribal agencies that evaluate and help guide fisheries and water quality management decisions on the river.
Joe Eilers and Kellie Vache of MaxDepth Aquatics, conducted and authored the study, measuring pH, temperature, nutrient composition, algae growth, and numerous other water quality parameters.
Additionally, the researchers built computer models to test various scenarios, forecasting how changes in climate or project operations might affect conditions in the river and reservoirs.
The study found that many factors are at play in the condition of the Deschutes — some natural and therefore difficult to control, others caused by human actions. "Phosphorus and nitrogen are the two nutrients most often linked to increased algae in lakes and rivers," explained Eilers. "Over 90% of the phosphorus entering Lake Billy Chinook appears to be from natural weathering of volcanic rocks, whereas the vast majority of nitrogen entering the lake, primarily from the Crooked River, is derived from human activity."
Several climate considerations, like low stream flows and rising regional temperatures, are also beyond the control of resource managers. But other changes in the river have been influenced by installation of the selective water withdrawal, a fish passage system completed at Round Butte Dam in 2010.
The structure was designed to reconnect the Deschutes above and below the Pelton Round Butte Project, and has successfully enabled the migration of fish in both directions for the first time since the dams were built in the 1950s and '60s, while restoring natural seasonal temperature patterns.
Highlights of the salmon reintroduction effort have included a strong return of adult upper basin sockeye in 2016, and the announcement last week that upper basin spring Chinook returns this year are running strong, despite poor returns elsewhere in the Columbia Basin.
But with the more interconnected ecosystem, the upper basin now has a more direct impact on the lower river. For instance, downstream algae growth is highly influenced by upstream runoff from urban and agricultural lands. Because the selective water withdrawal pulls water from both the surface and the depths of Lake Billy Chinook, and more nutrient-laden surface water is now passed directly downstream, the dams no longer "buffer" the lower river from those conditions the way they did before the new system was installed.
Those complex dynamics make finding solutions to "fix" every issue especially challenging. "Some of the changes we modeled could result in water quality improvements in the Lower Deschutes River, but virtually all of the scenarios involve trade-offs," said Eilers. "One change may elicit a beneficial response in one portion of the system, but might cause moderate to serious negative consequences elsewhere. There is no free lunch in reservoir management."
While the study offers no easy solutions, the Pelton Round Butte Fish Committee is already at work considering next steps. "This is a long-term project, and our direction will continue to be determined through collaboration with our partners and regulators, based on the best available science," said Hill. "Everyone wants a healthy watershed, and we're all working together toward that goal."
PGE and the tribes are hosting two upcoming open houses in Bend and Portland where members of the public can learn more and ask questions about the study. Information about those events, as well as the complete study, its data, and other resources can be found at PortlandGeneral.com/waterquality.
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