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Dreadful Dam Project Would Strand California's Salmon

Raising existing dams and building new ones could imperil California’s salmon population.

Raising existing dams and plans to build more could imperil California’s salmon population.

Raising existing dams and plans to build more could imperil California’s salmon population.

Krasowit/Shutterstock

California’s persistent drought has prompted elected officials, agency decision-makers and the concerned public to consider seriously innovative ways to stretch our finite water resources. The state is beginning to implement legislation that for the first time regulates California’s groundwater reserves. There is also encouraging discussion of measures such as requiring more efficient irrigation systems, treating more wastewater for reuse and capturing urban stormwater runoff.

But, in the midst of this forward thinking, the Bureau of Reclamation, the federal agency that operates the Central Valley Project (CVP), has stubbornly set its sights on the “solutions” of the past. The CVP and its state counterpart, the State Water Project (SWP), together form one of the world’s largest water projects. The historical mindset behind these projects is that we can “correct” for California’s dry climate through massive feats of engineering, capturing once free-flowing rivers behind dams and exporting water to irrigate arid lands and support the endless growth of distant cities.

The wholesale re-plumbing of the Central Valley watershed to create the CVP-SWP has wreaked havoc on the environment, drowning wild rivers, blocking salmon from reaching their former spawning grounds, and rendering flows below the dams too low and too warm to support healthy populations of native fish. A number of native species, including California’s iconic Chinook salmon, are perilously close to extinction, their once-abundant populations decimated by the low flows and high temperatures caused by decades of CVP-SWP operations. Too much water is taken out of California’s freshwater ecosystems for the species that evolved in those ecosystems to flourish, and perhaps even to survive.

An aqueduct carrying water through California's arid Central Valley.
An aqueduct carrying water through California's arid Central Valley.
Hank Shiffman/Shutterstock

Despite these problems, the Bureau of Reclamation’s answer to the current drought is to propose building more dams and raising existing ones. (Ironically, this is happening even as some old dams are being torn down to remediate the damage they’ve done to rivers and fisheries.) The first such proposal is a major expansion of the state’s largest reservoir, Shasta Lake in northern California. The proposal is to raise the dam 18.5 feet, which, in theory, would increase the reservoir’s storage capacity. But the current reservoir has only reached full capacity every four years or so during its 70-year existence, and even less frequently in recent years. In light of future reduced precipitation, rapidly declining alpine snowpacks that send melt-water to the reservoir in summer, and higher temperatures that will increase reservoir evaporation, it’s unlikely that raising the dam would increase storage in any but a handful of future years.

The price tag for the Shasta Dam raise is estimated at $1.4 billion. Experience with massive engineering projects suggests it could end up costing significantly more. But the dam raise’s true costs would be far higher, since it would destroy or severely damage a host of invaluable resources.

Among its most egregious costs would be the destruction of the majority of the remaining cultural and spiritual resources of the Winnemem Wintu Tribe. The tribe lost the core of its ancient heritage when Shasta Dam was completed in 1945, flooding ancestral homelands and blocking the salmon runs central to the tribe’s culture. The tribe vigorously advocates the creation of a swimway to allow salmon to bypass the dam and again spawn in the cold, clear waters of the reservoir’s tributaries. But the higher the dam, the harder it will be to create such a passage. The Winnemem Wintu were promised reparations for the past destruction of their lands, but these never came. Now, the Bureau of Reclamation proposes to inundate most of what is left of the tribe’s heritage under the expanded reservoir.

McCloud River
The McCloud River in northern California.
Photo by Don Graham/CC BY 2.0

In high-water years, the dam raise would also flood the lower reaches of the rivers and streams that feed the reservoir, including the McCloud River, a world-famous trout stream protected by California law, which the dam raise would violate. The higher dam would also flood several hundred miles of shoreline and threaten the existence of several species of animals and plants, including the Shasta salamander, that live nowhere else.

Nor would the problems end above the dam. The Bureau of Reclamation claims that one of the main purposes of raising the dam is to improve the survival of anadromous fish like salmon and sturgeon that hatch in fresh water, migrate to and mature in the ocean, and return to spawn in the Sacramento River below the dam.

But, according to the U.S. Fish and Wildlife Service and the California Department of Fish and Wildlife, 90 percent of the time, the dam raise would have either no effect or a negative effect on downstream survival of anadromous fish. In the remaining 10 percent of water years, the wildlife agencies concluded it might have some minor positive effect, but so minor as to be insignificant to the ultimate survival of these fish. The Fish and Wildlife Service, in a painstaking analysis of the project’s effects on wildlife and native plants, concluded that it could not support the Bureau’s proposal.

The final environmental impact statement on the Shasta Dam raise was recently released, though the Bureau of Reclamation has yet to make any final recommendations to Congress, which would have to authorize this ill-founded proposal and its funding.

California needs innovative, affordable, and effective solutions to its long-term water woes, not a return to the failed strategies of 70 years ago. Those strategies have produced degraded rivers and beleaguered wildlife that desperately need our help, not further injury.

This blog was originally posted by the San Francisco Examiner on September 29, 2015.

Tags:  Drought, Salmon, Water
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