Quagga mussel control program launched by Metropolitan Water Board

A comprehensive program was launched to detect and control an invasion of quagga mussels in the regional water import and treatment system that provides the Metropolitan Water District of Southern California with half its drinking water. The mussels, related to zebra mussels that have overrun the Great Lakes and Mississippi River, were found Jan. 6 in Lake Mead and at MWDSC's Whitsett Intake Pumping Plant on Lake Havasu and Gene Wash Reservoir, at the start of the Colorado River Aqueduct....

LOS ANGELES, Feb. 15, 2007 -- A comprehensive program to detect and control an invasion of quagga mussels in the regional water import and treatment system that provides the Southland with half of its drinking water was launched this week by the Board of Directors of the Metropolitan Water District of Southern California.

Quagga mussels, which are related to the notorious zebra mussels that have overrun the Great Lakes and Mississippi River watershed, were found Jan. 6 in Lake Mead, on the Colorado River, and were subsequently found at Metropolitan's Whitsett Intake Pumping Plant on Lake Havasu and the nearby Gene Wash Reservoir, at the beginning of the district's Colorado River Aqueduct.

The mussels, which are spread by commercial ships and recreational boats, can multiply rapidly, clog pipes and pumping machinery, and ruin the ecology of lakes and reservoirs. Importantly, once the ecology is altered, the growth of algae can occur and affect the taste of a region's drinking water.

"With recent evidence that quagga mussels have infested the entry portals of our Colorado River Aqueduct system, this is the initial stage of a three-phase program to detect, assess and control these invaders," said Metropolitan General Manager Jeff Kightlinger.

"This control program will not only protect critical water-supply infrastructure in Southern California, but will safeguard the extensive freshwater fisheries in our Diamond Valley Lake and Lake Skinner reservoirs," Kightlinger said.

The first phase of the program was approved unanimously by Metropolitan's board, and will be launched immediately with the purchase of $180,000 of portable decontamination units, deep-water surveillance equipment, automated water samplers, and a $16,000 polarizing microscope. It also includes increased surveillance of Metropolitan's aqueduct and reservoirs by divers and maintenance personnel, and laboratory inspections of water samples.

Dr. Ric De Leon, Metropolitan's microbiology manager, said the program's first phase should be completed in six months, at which time results and recommendations will be reported to Metropolitan's board.

The results of the surveillance, studies and vulnerability assessment conducted during the first phase will be used to prioritize infrastructure upgrades and develop control measures for subsequent phases of the program, and will include recommendations for changes in boating practices or additional facilities needed to control the spread of the mussels at Diamond Valley Lake and Lake Skinner.

During Metropolitan's initial quagga discovery -- the first verified finding of the mussel in California -- divers found low densities of the mussels, ranging in size from a quarter-inch to 1 ¼-inches wide, attached to concrete surfaces and anchors at depths of 30 to 40 feet during an inspection at the Whitsett Intake plant. Additional small numbers of quagga were found later at Gene Wash, which serves as a forebay for another nearby pumping plant along Metropolitan's aqueduct.

Although subsequent underwater inspections of Metropolitan reservoirs, including Diamond Valley Lake and Lake Skinner, have failed to turn up any additional mussels, Debra C. Man, Metropolitan's chief operating officer, said the district would take aggressive action to control the number of quagga in its aqueduct system and protect the district's raw (untreated) water conveyance system from further invasion.

"Controlling the spread of this mussel in our water system is a top priority for us," Man said. "We plan to take every action necessary to protect and maintain the reliability of our aqueduct, lakes, pipelines and other facilities."

The Metropolitan Water District of Southern California (www.mwdh2o.com) is a cooperative of 26 cities and water agencies serving 18 million people in six counties. The district imports water from the Colorado River and Northern California to supplement local supplies, and helps its members to develop increased water conservation, recycling, storage and other resource-management programs.

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Also see: "MWDSC Board moves to protect, preserve water education facility at Diamond Valley Lake: District will look for partners to develop, operate self-sustaining water education facility"

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