The Largest Dam Removal in U.S. History Has Begun

The largest dam removal project in American history took an irreversible step forward earlier this month when crews opened a 16-foot-wide tunnel in the base of the Iron Gate Dam in Hornbrook, California. That event marked the beginning of the end of a decades-long effort to restore the Klamath River, which snakes for more than 250 miles through Oregon and California, to a new natural state.

“This is historic and life-changing, and it means that the Yurok people have a future,” Amy Cordalis, a member of the Yurok tribe and one of the leaders of the effort to remove the dams, told NPR. “It means the river has a future, the salmon have a future.”

Members of the Yurok, Karuk, Hoopa, Shasta, and Klamath peoples, among others, have long worked to convince federal regulators that the four dams on the river — Iron Gate, Copco 1, Copco 2, and JC Boyle — have done more harm than good. Originally built a century ago as part of a hydropower development blitz in the American West, they blocked salmon and steelhead trout from reaching their habitats, decimating fish populations and robbing the tribal nations of a vital food source. The dams quickly outlived their usefulness: The amount of power they produce is negligible compared to the needs of the region today.

Copco 2, the smallest of the four dams, came down last fall; that one didn’t have a reservoir, which made it relatively easy to remove. Over the next few months, Iron Gate, Copco 1, and JC Boyle will all have their reservoirs drained, returning the river water to levels not seen since the early 20th century. By the fall, the last vestiges of the dams should be off the river.

The tribes have big plans for what comes next. An immense effort — funded, at least in part, by millions of dollars from the Bipartisan Infrastructure Law — is underway to revegetate the more than 2,200 acres of land that will be exposed when the reservoirs are empty, and with more than 17 billion seeds slated for planting and at least a thousand trees ready to be flown in by helicopter. Over time, the river will slowly turn back into the vibrant, free-flowing ecosystem it once was.

Those who were on-site when the tunnel was opened this month described seeing “chocolate-milk-brown water,” a “dark purge” containing both water and sediment flow through the dam. Sediment is an existential problem, and not just for the dams in the Klamath river — human-made barriers prevent silt from traveling downriver, and the sediment buildups block dams’ release gates, reducing their ability to both generate electricity and release water. This also affects downstream ecosystems, which evolved with a steady supply of fertile new soil. Once enough sediment builds up, a dam becomes practically useless.

The removal of the Iron Gate dam, then, is not just a service to the Native peoples and ecosystems along California’s second-largest river. It’s also the solution to a problem that has quite literally been building for decades.

“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, told the San Francisco Chronicle. “It’s what we’ve been fighting for: to see the river for itself.”