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Saving Klamath Lake:
the solution that could slip away

By Blake Edgar

Horne image
Alex Horne at Lafayette Reservoir. The Berkeley engineer and international expert on water quality says Upper Klamath and its fish populations would benefit from adding not water, but oxygen, to the shallow lake.
BART NAGEL PHOTO

Snowmelt flowing to the flat high desert of the Klamath Basin once fed a vast network of marshes and shallow lakes. Nearly a century ago, this region that spans the California-Oregon border was chosen for an ambitious federal farming effort. Dams were erected and canals excavated. Today, this massive Klamath Project provides crucial water for cattle ranchers and farmers of potatoes, onions, and alfalfa on 230,000 acres. But this being the West, where water flows, fights erupt.

The Klamath Project’s largest reservoir, Upper Klamath Lake in southern Oregon, supports two rare fish species, the Lost River sucker and the shortnose sucker. Populations of both species plummeted during the 1980s, so the fish were protected under the U.S. Endangered Species Act. Yet mysterious mass fish dieoffs still plague the shallow murky lake.

"If the lake were shallower, that would be fine," says Berkeley civil and environmental engineer Alex Horne. "If it were deeper, that would be fine. But where it is, is just the wrong depth."

Federal policy for the past decade has maintained the Upper Klamath Lake’s water level at higher than normal elevation for the suckers’ sake. Keeping more water in the lake for fish already meant that less was getting released to farmers. When in 2001, drought conditions prompted the U.S. Bureau of Reclamation to cut off all water diversions from the lake, local farmers mounted heated protests. A billboard that appeared at the time read: "Call 911 — Some sucker stole our water." Eventually, the farmers received a fifth of their usual water allotment.

During four decades of research on aquatic systems from Spain to California, Horne has confronted water quality problems and earned an international reputation for finding elegantly simple and environmentally sound fixes. About two years ago, the Klamath Water Users Association, a group of farmers and ranchers, asked Horne to help solve their problem.

Horne, whose straightforward engineering solutions successfully cleared up water at Camanche Reservoir on the Mokelumne River, insists that keeping more water in the lake won’t help and could place the fish in greater jeopardy. "You might think that more water is better," he says, "and in large lakes that would be true. But in shallow lakes the same rules just don’t apply."

Coot image
Horne proposes planting thousands of acres of reeds, which would act like filters, cleaning Klamath Lake of its nutrient-rich blue-green algae that rob fish of oxygen.
BART NAGEL PHOTO

While Upper Klamath Lake covers 70,000 acres, its average depth ranges a mere six to ten feet. Since fish kills have occurred there when the water level was above and below average, Horne sees no clear relationship between lake levels and lethal conditions.

Horne suspects another culprit. "When fish die like that, it means they've run out of oxygen," says Horne. That's not a problem for fish in deep, clear lakes like Lake Tahoe, he says, but Upper Klamath quickly accumulates nutrients from surrounding farms that promote water-clouding blooms of blue-green algae — cyanobacteria. These abundant microbes breathe day and night, competing with fish for oxygen.

Horne believes that the fish in Upper Klamath benefit from frequent nocturnal convective mixing that stirs oxygen-laden surface water down to the bottom, until calm, cloudy summer evenings come along and curtail the nightly mixing. When wind does return, the now stagnant deep water infiltrates the water column along with toxic hydrogen sulfide gas that builds up in the lakebed when oxygen is absent. "It's like mixing a foul brew," says Horne, "and that’s what causes the fish kills."

Instead of adding water, says Horne, add air. "If the fish are short of oxygen, we add it. This lake needs an emergency iron lung soon." Admittedly simple, Horne’s oxygenation solution has created clearer water in many Western lakes and is a common tool at overcrowded fish hatcheries. Using benign wind or solar power, oxygen could be pumped to the bottom of Upper Klamath Lake, forming instant refuges for suckers. Diffusers on the lakebed could aerate surface water and prevent the stratification that restricts oxygen at depth. At a cost as low as $50 per ton of oxygen, Horne says, it’s affordable. "The great thing about oxygenation is that it's dirt cheap."

Horne testified before Congress with his solution in 2001, but the dueling interest groups — politicians, farmers, and biologists — who keep a watchful eye on Klamath Lake have yet to agree. Critics say Horne’s plan either won’t work or doesn’t address the lake’s ongoing problems.

But Horne remains confident that his solution will work, and work immediately. He knows there’s a larger pollution problem behind Upper Klamath’s murky green water — a problem he would solve by engineering the wetlands with thousands of acres of reeds and other native plants to trap nutrients and modify the water flow patterns through the wetlands.

For now, though, no technology exists to detoxify the lake's sediments. Although the latest government guidelines for managing Upper Klamath Lake omit any mention of oxygenation, a recent report by the independent National Research Council concluded that there was no scientific basis for the federal policy to keep more water in the lake. That gives Horne hope that political currents could change, allowing him to demonstrate what a little, or especially a lot, of oxygen could do.

"We’re working to change the conventional wisdom," says Horne, "and for Klamath Lake the clock is ticking. Suckers live a long time — they’re tough as old boots — but they only have a decade or two. Let’s keep the fish alive, and then we’ll clean up the whole lake with a long-term solution."


Blake Edgar, science acquisitions editor at University of California Press and former senior editor of California Wild, has co-authored three books on paleoanthropology, including The Dawn of Human Culture and From Lucy to Languages. His work appears in Bay Area and national magazines.


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