WASHINGTON DC – Federal agencies announced Thursday they will update the environmental guidelines that shape how they operate 14 dams on the Columbia and Snake rivers.

The move follows a decadeslong legal battle that Native nations, environmental advocates and fishing groups are fighting to get the government to take aggressive action on salmon recovery. A lot of that battle has focused on removing dams on Washington’s lower Snake River.

The fight came to a head in 2020 when federal agencies released the current guidelines for the federal system’s operations — known as the Columbia River Operating System Environmental Impact Statement — which came out against removing the four lower Snake River dams.

Environmental groups and others sued in response. Then, in late 2023, the lawsuits were paused in an agreement between federal agencies, the states of Washington and Oregon, environmental advocates, fishing groups, Native nations and the Biden administration.

That agreement required federal agencies to weigh if new guidelines were necessary. The U.S. Army Corps of Engineers and Bureau of Reclamation have now decided they are.

The guidelines at the center of this shape many crucial aspects of the Columbia River dams’ management — including how much water is used to generate hydroelectricity versus how much passes over spillways to help young salmon safely make it to the ocean.

The move to pursue new guidelines sparked celebration among environmental and fishing advocates and condemnation from business interests that depend on a dammed lower Snake.

“At least four Columbia and Snake River salmon and steelhead stocks have already gone extinct and 13 others — including all four remaining Snake River stocks — are listed under the Endangered Species Act,” Northwest Sportfishing Industry Association Policy Director Liz Hamilton said in a statement.

“Revising (the guidelines) is the logical next step toward meaningful change that complies with the law and the needs of the fish,” she added.

Earthjustice attorney Amanda Goodin emphasized that avoiding regional salmon extinction is possible if the agencies commit to needed actions “including breaching the four lower Snake River dams and replacing their services.”

In a joint statement, powerful agriculture, shipping and hydropower interests highlighted the lower Snake dams’ significant role in the region’s economy and called the move to update the guidelines unlawful.

“The coalition contends that a new National Environmental Policy Act (NEPA) analysis would be both premature and unlawful, warning that it would be incomplete and could mislead the public about these dams’ vital role in supporting the region’s economy and environment,” their statement read.

The next step in the process of updating the guidelines — known cumulatively as completing a supplemental environmental impact statement — is public feedback.

That will take the form of a 90-day public comment period, said Tom Conning, spokesman for the Corps, which operates 12 of the dams.

“The goal is really to get the public to be aware,” he said. “We’re trying to get the public to send comments to us for consideration.”

Conning said the comment process isn’t like voting, where the goal is to select the most popular ideas. Instead, it’s about people raising issues the agencies might not have considered to make sure the guidelines include as many factors and potential side effects as possible.

Next, the agencies will release a draft supplemental environmental impact statement, followed by another public comment period. The process will end when the agencies release the final supplemental environmental impact statement.

While it’s unclear how long the whole process will take, the more intensive 2020 review lasted just over four years.

To produce the guidelines, the agencies will have to weigh two dozen interconnected factors — each with significant environmental, economic and social consequences across the roughly 260,000-square-mile Columbia River Basin. Any decision is bound to anger parties across the basin that will take the issue to the courts.

On one hand, hydropower is increasingly valuable because of massive increases in demand for electricity from the tech industry, especially data centers. That’s compounded by rising population in the Pacific Northwest and fast-approaching fossil fuel-free grid deadlines in Washington and Oregon.

The four lower Snake River dams produce about 5 percent of the region’s electricity — worth between $415 million and $860 million a year. They also allow grain barges to navigate to Lewiston, Idaho, moving 60 percent of Washington’s roughly $750 million in yearly wheat exports.

The overall cost of replacing the dams could be in the tens of billions of dollars each year, according to the Congressional Research Service — especially if the removal is accompanied by massive investment in hard-hit regions to offset the economic toll, which environmental groups and even a Republican congressman have argued for.

But the harmful impacts of the lower Snake dams on salmon are documented by a growing number of government reports, which show the dams are driving salmon extinction by blocking the fish from historic spawning grounds, favoring predators and other means.

Environmental research groups echo that, noting, “Since construction finished on these four dams in the 1970s, wild Snake River salmon populations have plummeted by more than 90 percent.”

Recent estimates show salmon returns to the Columbia have averaged about 2.3 million fish a year for the past decade — a fraction of the 10 million to 16 million that came before dams.

And that 2.3 million estimate doesn’t differentiate between wild and hatchery fish. A 2022 NOAA assessment found the number of wild salmon spawning in Columbia River tributaries declined substantially for nearly every salmon run in nearly every river they measured between 1990 and 2019.

In addition to practical concerns, federal agencies must also navigate a minefield of political uncertainty caused by January’s transition in the presidential administration, as well as shifts in Congress.

Conning said that while every administration brings change, the agencies will not be changing course.

“We’re following federal laws to guide what we’re doing,” he said. “And we can’t really speculate on the incoming administration and next Congress, and what they might do.”

Republicans, who will control the presidency and both the chambers of Congress starting in January, have opposed Snake River dam removal.

During his first term, former and future President Donald Trump showed a clear preference for cutting environmental protections for fish and ecosystems, instead increasing the amount of river water available across the West for farming. He doubled down on that stance while campaigning last summer, The Columbian reported in October.

Whatever the agencies decide on Snake River dam removal, the issue will ultimately have to be decided by Congress.

It’s unclear how negotiations on the Columbia River Treaty between the U.S. and Canada — and a stopgap agreement between the two countries on hydropower generation and flood control — might shape the agencies’ choices.

Public comments on the update can be left at www.nwd.usace.army.mil/columbiariver. The Corps and Reclamation will hold at least three virtual public meetings the week of Feb. 10.