The plan, announced in December, stopped short of calling for the removal of four controversial dams on the Snake River, as some environmental groups and tribal leaders have urged. But officials said it would boost clean energy production and help offset hydropower, transportation and other benefits provided by the dams should Congress ever agree to breach them.

The plan brokered by the Biden administration pauses long-running litigation over federal dam operations and represents the most significant step yet toward eventually taking the four Snake River dams down. The plan will strengthen tribal clean energy projects and provide other benefits for tribes and other communities that depend on the Columbia Basin for agriculture, energy, recreation and transportation, the White House said.

“Since time immemorial, the strength of the Yakama Nation and its people have come from the Columbia River, and from the fish, game, roots and berries it nourishes,” Yakama Nation Chairman Gerald Lewis said at a White House ceremony.

“The Yakama Nation will always fight to protect and restore the salmon because, without the salmon, we cannot maintain the health of our people or our way of life,” Lewis said, adding that Columbia Basin salmon are dying from the impacts of human development.

“Our fishers have empty nets and their homes have empty tables because historically the federal government has not done enough to mitigate these impacts,” he said. “We need a lot more clean energy, but we need to do development in a way that is socially just.”

Lewis was among four tribal leaders who spoke at the hourlong ceremony at the White House complex, along with Washington Gov. Jay Inslee, Oregon Gov. Tina Kotek and an array of federal officials.

The agreement, formally known as the Columbia Basin Restoration Initiative, “deserves to be celebrated,” said Jonathan W. Smith, chairman of the Confederated Tribes of the Warm Springs Reservation.

The settlement “takes the interests of all the stakeholders in the Columbia Basin into account,” he said. “It lays out a pathway to restore salmon and steelhead to healthy and abundant levels and moves forward with the necessary green energy transition in a socially just and equitable way.”

Corinne Sams of the Confederated Tribes of the Umatilla Indian Reservation called the signing ceremony a historic moment, not just for the tribes, but also for the U.S. government “and all Americans in the Pacific Northwest. My heart is big today.”

The Columbia River Basin, an area roughly the size of Texas, was once the world’s greatest salmon-producing river system, with at least 16 stocks of salmon and steelhead. Today, four are extinct and seven are listed under the Endangered Species Act.

Dams are a main culprit behind the salmon’s decline, and federal fisheries scientists have concluded that breaching the dams in eastern Washington on the Snake River, the largest tributary of the Columbia, would be the best hope for recovering them, providing the fish with access to hundreds of miles of pristine habitat and spawning grounds in Idaho.

Conservation groups sued the federal government more than two decades ago in an effort to save the fish. They have argued that the continued operation of the dams violates the Endangered Species Act as well as treaties dating to the mid-19th century ensuring the tribes’ right to harvest fish.

Friday’s celebration did not include congressional Republicans who oppose dam breaching and have vowed to block it.

Dams along the Columbia-Snake River system provide more than one-third of all hydropower capacity in the United States, said Rep. Cathy McMorris Rodgers, a Washington Republican who chairs the House Energy and Commerce Committee. In Washington state, hydropower accounts for 70% of electricity consumed.

The Snake River dams “helped transform Eastern Washington into one of the most productive agricultural regions in the world,” including 40% of America’s wheat, Rodgers said in a statement.

She denounced “secret negotiations” led by White House senior adviser and climate envoy John Podesta, saying he and other officials “worked behind closed doors with a select group of radical environmentalists to develop a secret package of actions and commitments” that advance ”efforts to remove the four Lower Snake River dams.”

Biden officials “ignored the concerns of people who live in the Pacific Northwest and who would be significantly impacted if these dams were breached,” Rodgers said.

Podesta and other speakers at the White House ceremony looked past those concerns, with few even mentioning the dams.

“President Biden understands that the Columbia River is the lifeblood of the Pacific Northwest, for its culture, for its economy and for its people,” said Brenda Mallory, chairwoman of the White House Council on Environmental Quality.

“The historic agreement is charting a new and exciting path to restore the river, provide for clean energy and live up to our responsibilities and obligations to tribal nations,” Mallory said. “I’m confident we will secure the vision … of securing a restored Columbia River Basin, one that is teeming with wild fish, prosperous to tribal nations, (with) affordable clean energy, a strong agricultural economy and an upgraded transportation and recreation system.”