AUSTIN, Texas – Zebra mussels are infesting two Texas lakes and biologists fear them spreading, according to the Texas Parks and Wildlife Department.

Lake Georgetown and Lake Livingston are reportedly infested with the invasive mussels. The species poses an environmental and economic threat.

Each female mussel can produce up to one million larvae which can spread downstream. The mussels can cover beaches with dangerously sharp shells, destroy hydroelectric facilities and damage boats.

North of Austin, biologists found larvae in Lake Georgetown during routine water testing on Oct. 27. A follow-up survey found young zebra mussels attaching to rocks along the lake’s shore.

“This is very unfortunate news because as recently as spring 2017 all routine plankton samples have tested negative for zebra mussel larvae and we hadn’t found any juveniles or adults,” said Brian Van Zee, TPWD inland fisheries regional director. “It just goes to show how rapidly zebra mussels can colonize and establish themselves in our lakes once they are introduced.”

The Georgetown utilities department has monitored the lake for the past few years, knowing an infestation was possible. Now that it's been confirmed, officials are working on their next move, but they don't think the pests will be too costly.

"Our actions now are to determine what maintenance we need to do or preventive maintenance that's necessary," said Glen Dishong, utilities director. "We will have to get divers at some frequency to get down and check our intake structure and see if the mussels are attached and if they have we will have to remove them."

At this time, the city doesn't expect additional costs or increases in water rates.

Controlled by the Trinity River Authority, Lake Livingston is located north of Houston. The lake previously tested positive for zebra mussels, but was upgraded to infested-status after research by Dr. Christopher Churchill from the U.S. Geological Survey.

Boat-owners are encouraged to help slow the spreading of the mussels by properly cleaning, draining, and drying boating equipment before leaving boat ramps. Anyone who spots zebra mussels at the lakes are asked to report it to the TPWD.

Biologists will continue to monitor the spreading of the mussels along with the Brazos River Authority and the U.S. Army Corps of Engineers.

These recent infestations bring the statewide total to 13 lakes. 

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