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Saving Klamath Lake:
the solution that could slip away
By Blake Edgar
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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."
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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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