The Klamath River, as seen from Highway 96.Xavier Mascare/TNS/ZUMA

This story was originally published by the Guardian and is reproduced here as part of the Climate Desk collaboration.

Explosions roared through the canyons lining the Klamath River earlier this year, signaling a new chapter for the region that hugs the Oregon-California border.

In October, the removal of four hydroelectric dams built on the river was completed—the largest project of its kind in US history.

The blast of the final dam was just the beginning. The work to restore the river, which winds 263 miles from the volcanic Cascade mountain range in Oregon to the Pacific coast in northern California, is now under way. Already it’s been among the most hopeful environmental stories of past years.

“It has been more successful than we ever imagined,” said Ren Brownell, the spokesperson for the Klamath River Renewal Corporation, a nonprofit created to oversee and implement the removal, adding: “There’s an incredible amount of joy.”

The Klamath River was once an ecological powerhouse—the third-largest salmon-producing river in the American west. Its basin covered more than 9.4 million acres and its network of wetlands was the largest in the region. The ecosystem was home to millions of migrating birds. Tribes including the Hoopa, Karuk, Klamath, Modoc, and Yurok thrived in this bountiful and beautiful watershed for thousands of years, with the river providing both sustenance and ritual.

Over the last hundred years, these landscapes have been drastically altered.

After the first dam began operating in 1918—one of four that would eventually be forged in the lower Klamath to provide hydroelectric power to communities nearby—the course of the river was changed. The dams obstructed the migration of salmon and other native species, which help carry nutrients into the systems from the ocean, to cascading effects.

They also held on to huge stores of sediment that would otherwise have flowed downriver, and created shallow reservoirs that quickly heated when the weather warmed. Increased water temperatures in the river allowed toxic algal blooms to thrive.

In recent decades, the climate crisis has turned up the dial, deepening droughts and fueling a rise in catastrophic fire as the region grows ever hotter. The impacts only increased as more water was diverted to support the farming and ranching in the region, and more habitat was altered by mining and logging.

Twenty-eight types of salmon and steelhead trout, seen as indicator species that represent the health of the ecosystems they live in, have been

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