Environment

California is about to begin the nation’s largest dam removal project. Here’s what it means for wildlife

REDDING – After decades of negotiation, the largest dam-removal project in US history is expected to begin in California’s far north next year.

The first of four aging dams on the Klamath River, the 250-mile waterway that originates in southern Oregon’s towering Cascades and empties along the rugged Northern California coast, is on track to come down in fall 2023. Two others nearby and one across the state line will follow.

The nearly half-billion dollars needed for the joint state, tribal and corporate undertaking has been secured. The demolition plans are drafted. The contractor is in place. Final approval could come by December.

Now, among the last acts of preparation, scientists are trying to make sure the fish and wildlife that are intended to benefit from the emergence of a newly wild river will thrive. While the decision to remove the hydroelectric dams was financial, it was urged —and enabled – by those hoping to see a revival of plants and animals in the Klamath Basin.

The native flora and fauna in the region are bound to prosper as algae-infested reservoirs at the dams are emptied, the flow of the river quickens and cools, and river passage swings wide open.

“At its heart, this is really a fish-restoration project,” said Mike Belchik, senior fisheries biologist for the Yurok Tribe, which has long lamented the decline of salmon on its ancestral territory in the basin. “That’s why we’re doing this.”

In one of the latest and most significant tests of how fish may fare, a team of scientists recently released thousands of juvenile salmon into the rivers and creeks upstream of the dams, areas where fish migrating up the Klamath have not been able to go since the dams blocked access more than a century ago.

The researchers are tracking these “experimental” salmon with the goal of learning whether more than 300 miles of waterways in the upper Klamath Basin are still navigable and fit for fish. As it stands now, fish swim upriver but are stopped at the dams, an impasse considered detrimental to their numbers.

“The landscape is a lot different now than it was,” said Mark Hereford, fish biologist at the Oregon Department of Fish and Wildlife, who is leading the study on fish passage in the Klamath Falls area of ​​Oregon. “There are uncertainties we have about how the fish will do as they migrate through the system.”

The concerns run the gamut. Urban development has crowded out wetlands. Recently established invasive fish could prey on natives. Communities may be drawing too much water from rivers and creeks.

At stake is nothing less than the future of the cherished chinook salmon run. The fish once numbered in the hundreds of thousands in the Klamath River, making its migration the third largest salmon run on the West Coast. Only populations in the Columbia and Sacramento rivers were larger.

Today, the celebrated fall run of chinook is a fraction of what it was, less than 10% by some estimates, contributing to the sharp contraction of commercial salmon fishing on the California coast. On at least one occasion, the Yurok Tribe even stopped serving local salmon at its annual Klamath Salmon Festival.

James Whelan, a graduate student at Cal Poly Humboldt, surgically implants radio transponder tags in a juvenile chinook salmon before the fish is released.

James Whelan, a graduate student at Cal Poly Humboldt, surgically implants radio transponder tags in a juvenile chinook salmon before the fish is released.

Mark Hereford / Oregon Department of Fish & Wildlife

The test fish being released by Hereford and his team will not just help preview the fate of chinook and whether the new terrain can help the salmon rebound. It will also provide a glimpse of what’s in store for other struggling fish that have historically migrated from the ocean to the upper Klamath Basin. These include coho salmon, steelhead trout and Pacific lamprey.

“There’s a lot of habitat up here. There’s enough habitat to support a lot of fish, “Hereford said. “The results of this project are going to be exciting.”


From the window of a Cessna 210 on a recent afternoon, the stunted flow of the once steadily-moving Klamath was visible below. On the California portion of river, one dam after another brought water to a virtual standstill.

The smallest of the three California dams and the first scheduled for removal, 33-foot-tall Copco No. 2, diverts water to a powerhouse to generate electricity. The other two, 173-foot Iron Gate Dam and 126-foot Copco No. 1, produce power as well as hold back large reservoirs that pool water amid sprawling hills just south of the state line.

A fourth dam scheduled for elimination, JC Boyle, is in Oregon, about 12 miles north of the border. Two other dams above JC Boyle, considered less harmful to wildlife, will remain.

Leave a Comment