The Klamath River in California and Oregon is one step closer to a healthy new beginning.

Officials gathered earlier this month at the Iron Gate Dam in Hornbrook, California, to unlatch a gate at the base of its reservoir. As the water flowed through, it signaled the beginning of the end of the largest dam removal project in United States history, report Erik Neumann and Juliet Grable for NPR.

The gate’s opening, formerly just a crack, was extended to three feet wide. Dark brown waters rumbled through the gap, washing years of sediment buildup downriver. Over the next week, 2,200 cubic feet of water per second were expected to flow, lowering the reservoir between two and four feet per day. Eventually, the channel’s entire width—stretching 16 feet across—will allow the uninhibited passage of water and sediment.

Opening the Iron Gate Dam represents a critical advancement in the historic demolition project, which was approved by the Federal Energy Regulatory Commission in November 2022. The effort will remove four aging hydroelectric dams in the Klamath River, restoring hundreds of miles of salmon habitat. The first and smallest dam, Copco 2, was already deconstructed this past autumn, and the rest are slated for removal this year.

“This is historic and life-changing,” Amy Cordalis, an attorney and Yurok Tribe member, says to NPR. “And it means that the Yurok people have a future. It means the river has a future; the salmon have a future.”

The Iron Gate Dam, at 173 feet tall, is the smallest of the dams remaining on the Klamath River, which flows 260 miles from its headwaters in Oregon’s Cascade Mountains to the Pacific Ocean in Crescent City, California.

Last week, the John C. Boyle Dam, located the farthest upriver and about 12 miles north of the California-Oregon border, met a similar fate, as its reservoir was drained over 17 hours. The fourth and final dam, called Copco 1, will soon follow. Between five and seven million cubic yards of sediment—consisting of dead algae, silt and clay—stuck behind the three dams will be washed downstream, Ren Brownell, spokesperson for the Klamath River Renewal Corporation, tells Jefferson Public Radio.

By June, officials say, the Klamath River will return to its historic channel. All that will be left to do is to remove the obsolete infrastructure.

“Not to get too mushy about it, but being able to look at the river flow for the first time in more than 100 years, it’s incredibly important to us,” Frankie Myers, vice chair of the Yurok Tribe, tells the San Francisco Chronicle’s Kurtis Alexander. “It’s what we’ve been fighting for: to see the river for itself.”

Many communities, especially the region’s tribes—self-described “Salmon People,” including the Yurok, Karuk, Shasta, Klamath and Hoopa Valley, among others—rely on salmon as a subsistence food, but the Klamath River dams have disrupted their relationship with the fish for decades.