Quagga varmints invade county
Worrisome mussels found in San Vicente Reservoir

By: GIG CONAUGHTON - Staff Writer | Tuesday, August 21, 2007 9:01 PM PDT ∞

SAN DIEGO -- The hope that an exponentially multiplying mussel that has invaded California could be controlled before it reached San Diego County evaporated this week when tests showed quagga mussels in the San Vicente Reservoir near Lakeside.

The mussels don't threaten the water supply, but they have cost agencies and ratepayers billions of dollars to clean up in the Midwest and Great Lakes.

Gary Eaton, director of operations for the San Diego County Water Authority, said biologists at Portland State University confirmed that the "veligers" -- the microscopic larvae found at San Vicente -- were quagga mussels.

Eaton said the Water Authority was working with the California Department of Fish and Game and the Metropolitan Water District of Southern California to create a group that could develop a plan to control the mussels.

Fish and Game officials, meanwhile, immediately suggested that officials -- and the public -- take steps to ensure that boaters, Jet Ski operators and others using San Vicente properly clean equipment and bilges to make sure the mussel was not spread to other reservoirs. The city of San Diego owns the San Vicente Reservoir and stores water supplied by the Water Authority through some of its 270 miles of pipelines in the lake.

Water and wildlife officials have been scurrying to search for and kill the quagga mussels since January, when they were discovered in reservoirs of the Colorado River. That river helps supply drinking water to nearly 18 million Southern Californians in six counties, including San Diego.

Until then, the Ukrainian mussel had never been found near California.

Metropolitan -- Southern California's main water supplier -- actually drained the length of the 242-mile Colorado River Aqueduct for 10 days last month to chlorinate, dry out, and otherwise kill any quagga larvae in the system.

Despite that, the mussel now has spread all the way south, through untreated water pipelines or by larvae-carrying boats, to San Diego County.

Environmental scientists believe that the roundish mussel, which is often the size of a fingernail but can grow to slightly larger than a silver dollar, was brought to the United States in the 1980s in ballast water from foreign ships.

The mussel, which has no natural predators in this part of the world, has become a huge and expensive problem in the Great Lakes. Officials say it creates several problems. The mussel attaches itself to all types of hard surfaces, such as boats, docks, even engines. It can also attach itself to pipeline and filter openings, pumping equipment, and filter screens, restricting water flow.

The mussel is also voracious, often eating phytoplankton and suspended particles in the water, robbing fish and other aquatic species of their natural food supply.

Having the mussel cleanse the water can also let sunlight reach deeper into lakes and reservoirs than it otherwise would, creating algae blooms that could kill off fish and other aquatic species.

The mussel also does not provide an enticing meal for people. Because it can accumulate organic pollutants in its tissues up to 300,000 times greater than concentrations in the environment, officials suggest that people who try to eat the mussel could get sick.

But, at the moment, the biggest problem that the mussel presents water officials is its prolificacy.

"One female can produce 1 million eggs," said Alexia Retallack, spokeswoman for the state Department of Fish and Game's quagga mussel task force.

"(They) can overheat boat motors, they'll pull buoys under from their weight," Retallack said. "They're just a nasty pest."

Metropolitan officials, who updated board members Monday about the quagga infestation, said that in early January, divers and workers were only finding the mussels in small numbers. But those officials said that since January, they've been seeing a tenfold increase in those numbers every two months. Metropolitan officials said they've started adding thousands of gallons of chlorine into parts of the Colorado River Aqueduct system in the hope of killing, and controlling, quagga populations.

Jim Fisher, deputy director for the city of San Diego, said that city officials were still talking with fish and game, Water Authority and Metropolitan officials to decide whether to increase boater education and inspection efforts at San Vicente.

Eaton, meanwhile, said that the Water Authority needs to create a plan to try to control the mussel in part because San Vicente is eventually supposed to become linked to other local reservoirs as part of the $800 million "emergency storage project." The project would link San Vicente, Olivenhain Reservoir and Lake Hodges to give local residents a six-month supply of water in case of emergencies or disaster.

-- Contact staff writer Gig Conaughton at (760) 739-6696 or gconaughton@nctimes.com.

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