The Willamette River, the aqueous arterial that defines much of Western Oregon, is in trouble.

Last week, the advocacy group American Rivers, named the Willamette to its top-10 list of endangered rivers in the country, a dubious distinction that the group hopes will draw attention to the perils facing the waterway.

Of course, the river itself is not endangered. The headwaters in the Cascades will continue to channel rainfall and gush snowmelt into the 13 tributaries that contribute to the 187-mile waterway, which drains nearly 12,000 square miles. But while the river itself won’t soon go extinct, the same can’t be said for two endangered species of fish that have come to define its troubles: spring chinook and winter steelhead.

The existence of these iconic species is threatened by a number of factors, but their primary threat, according to American Rivers, is loss of access to habitat, cut off by more than a dozen dams that keep the Willamette Valley from flooding.

A 2008 federal document mandated changes to those dams to make migration easier for the threatened fish, but according to advocates, the agency in charge of the dams has dragged its feet, delayed projects and failed to allocate adequate funding that could help save the endangered species.

“It’s like they’ve been operating in slow motion,” said David Moryc, senior director for public lands policy at American Rivers. “The fish can’t wait any more.”

Historically, the Willamette River has been home to the spawning grounds of roughly half a million fish, many of them coveted salmonids like spring chinook and winter steelhead. Adult fish swim upstream, past the mists and roar of Willamette Falls, to lay their eggs in Cascade and coast range creeks and streams. Newly hatched juvenile salmon then navigated the same course in reverse, swimming down the unimpeded streams to mature in ocean waters before returning to their inland spawning grounds to hatch the next generation.

That’s how things worked for thousands of years. Then, in the 1950s and ’60s, federally-managed dams sprung up on the McKenzie, Santiam and multiple forks of the Upper Willamette. The dams were built for flood control to protect the growing population centers that dot the Willamette Valley, now home to 75 percent of the state’s population.

Locations of dams on the Willamette River system.

But most of the dams were built with faces hundreds of feet tall, impossible hurdles for migratory fish looking to return to their historic spawning grounds. Over the ensuing decades, the number of salmonids returning to the rivers to spawn plummeted. In 1999, the Upper Willamette spring chinook and winter steelhead were given protections under the Endangered Species Act.

Bob Rees, grew up in Northeast Portland and has been fishing on the Willamette and its tributaries since he was a boy. He’s been guiding fishing trips on the river for the last 23 years and now serves as executive director of the Northwest Guides and Anglers Association. Rees has seen the decline of steelhead and chinook firsthand.

Early in his career, Rees said salmon runs fluctuated on the river, with good years and bad. Recently, though, he said runs of the endangered fish have “tanked.”

“The fisheries have just about disappeared,” he said. “The writing is on the wall.”

In 2007, Willamette Riverkeeper sued the feds and the result of that litigation was a document called a Biological Opinion, which laid out specific steps that needed to be taken to protect the imperiled fish from the dams, which are referred to as the “Willamette Project” in the document.

”The Upper Willamette River Chinook is currently at a high risk of extinction,” the Biological Opinion reads. “The Willamette project contributes to this risk by blocking access to major spawning and rearing habitat for four of seven Chinook populations, and by degrading their remaining downstream habitat.”

That was more than a decade ago. Things have only gotten worse for the fish since then.

The Cougar Dam on the McKenzie River..LC-

The Army Corps of Engineers, the agency that built and manages the Willamette River dam system, was charged with improving fish passage for adults swimming upstream, juveniles headed out to the ocean and water temperature below the dams where warm water acted as a barrier to returning salmon.

Some of those projects have been completed — the corps has spent nearly $225 million on improvements to the dam system since the Biological Opinion was issued and some species have been removed from the endangered species list, at least in part, because of those improvements. But, more than 10 years after the Biological Opinion, others are still in the works and some haven’t been started yet as spring chinook and winter steelhead .

The Biological Opinion called for construction of a downstream passage facility at Cougar Dam on the McKenzie river by 2014. The project proved more complex than originally anticipated, according to Laura Bennett, a spokeswoman for the Army Corps of Engineers, and the deadline was pushed back.

The draft of the environmental assessment for construction was released in January of this year with completion of the project anticipated by 2022.

Detroit Dam. Scott Learn/The OregonianLC- The Oregonian

Similar projects are supposed to be completed at the Lookout Point Dam on the Upper Willamette by 2021 and at Detroit Dam on the Santiam River by 2023. The Detroit project has been broken up into two phases with the first to be completed in 2024, Bennett said, and the second by 2028.

The Lookout Point project will begin a series of “check-ins” this year, but there is no timeline for when construction would be completed.

“Challenges exist in implementing large-scale downstream passage actions in regards to effectiveness and cost,” Bennett said in an email. “But the Corps is adapting these projects as we learn new information.”

The cost is not just the federal government’s to bear, though. Many of the dams hold back reservoirs that supply water to cities and farmers. Those reserves support recreation and the tourist dollars that come with it. Any disruption to the reservoirs would, at least in the short term, create hardship for those that depend on them.

But Bob Rees, the fishing guide, said he, too, is losing money as the fish population dwindles, but that a long-term solution is the only one that makes sense.

“Tourist dollars are very important to the economy,” he said. “But we’re talking about the extinction of spring chinook in the whole basin. Who could justify how we do business if we watch as a whole species winks out?”

The latest budget proposal from the federal government included drastic cuts to construction funds to the Army Corps of Engineers, which prompted a letter from Oregon legislators urging the lawmakers to fully fund the agency.

“The (Army Corps of Engineers) is required by law to mitigate for impacts by the dams to the state’s iconic salmon and steelhead populations and as they hit a crucial milestone in that work, a reduction in construction funding could exacerbate the issues they’re currently working to address,” reads the letter, which was signed by all four of the state’s Democratic members of congress.

Moryc said that’s what endangered designation for the Willamette is all about, getting the public to weigh in on the process as the Corps revises its plans and to generate support for Oregon’s members of congress as they ask for the necessary funds.

“We already have a plan that’s 10 years old that hasn’t been implemented, and we are headed in the wrong direction” he said. “The can’t wait another 10 years.”

-- Kale Williams

kwilliams@oregonian.com

503-294-4048

@sfkale

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