Invasive mussels in South Bay reservoirs

SAN JOSE, CA

The mussels have already been found in one reservoir, and today, divers began taking samples from ten others -- starting with the Calero Reservoir, south of San Jose.

Divers are taking samples from ten Bay Area bodies of water in the coming day, starting with those in Santa Clara County. They're looking for a non native, very invasive species of mussel. If it is in Bay Area waters the damage it could cause would be costly.

Calero Reservoir is home to catfish and bass. Fish and Game wardens fear non native mussels are now moving in. Quagga mussels, originally from Russia, would be disastrous in U.S. waters. They're aggressive, they multiply quickly, and they were found in a San Benito County reservoir, last month.

If the mussels attached to themselves to a boat there, they could re-populate once that boat is launched anywhere.

"Once it becomes established, it's very difficult, if not impossible to remove it from a reservoir like this. You could drain it and do a number of different things, but the end result is you'll probably still not get rid of them," says Pat Foy, Fish and Game Warden.

The worst case scenario is what happened in the Great Lakes area back in the 90's. A massive colony of mussels like this actually clogged up the water lines which impacted the hydro electric current system. It ended up costing the power plant $3.1 billion dollars.

The Santa Clara Valley Water District is worried about Calero's central water level control valve.

"They can actually keep you from opening a valve and can reduce the efficiency of a valve or pipe," says Bruce Cabral, Water Quality manager, Santa Clara Valley Water District

Divers scoured the reservoir looking for signs of these mussels, but found nothing. Water samples were taken, just in case. The mussel's presence would also have a major impact on the eco-system.

"It's a good fishing lake, so I'd hate to see something like that happen to it," says Jim Hanley, fisherman.

The key to stopping the spread is boaters. Officials will do random boat checks until it's clear and the mussel threat is gone.

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