Zebra mussels have been confirmed in Ray Roberts Lake, state parks officials announced late Wednesday.
The discovery comes three years after the destructive, invasive species was found in Lake Texoma.
Originally from Eastern Europe, zebra mussels were first found in Lake St. Clair, Mich., in 1988. They have been found in more than 600 lakes or reservoirs in 29 states. Ray Roberts is the second Texas lake found to have zebra mussel colonies and the first in the Trinity River basin.
Park officials made the discovery after DNA analysis of water samples were taken from 14 North Texas reservoirs, 12 of which came back negative. Carter Smith, Texas Parks and Wildlife Department executive director, called the finding “very bad news.”
Department spokesman Mike Cox said that some mussels were found below the dam at Ray Roberts Lake but none elsewhere.
“They checked Lewisville Lake this afternoon and didn’t find anything,” Cox said in an interview Wednesday.
Zebra mussels can clog public water intake pipes and other underwater equipment by completely covering anything left underwater. The mussels’ razor-sharp edges also make recreation hazardous.
The mussels compete with baitfish for available forage, which affects game fish such as bass, striped bass and catfish. Zebra mussels will also colonize on the shells of native mussels and suffocate them.
Denton, which draws its water from Ray Roberts Lake as well as Lewisville Lake, could be immediately impacted.
“Obviously we’re very concerned that zebra mussels can have a negative impact to our water impact system at either Ray Roberts Lake or Lewisville Lake. This in turn could lead to costly repairs of our infrastructure, which obviously could impact our water rates,” said John Cabrales, spokesman with the city of Denton. “Obviously, there’s no easy answer to eradicate these mussels, otherwise other states would have done so.”
Cabrales said though the mussels are not big in size, “there’s so many of them that collectively, they became a massive entity to deal with.”
The news does not come as a complete surprise to city officials.
“We knew it was a matter of time before they would transfer,” Cabrales said.
The North Texas Municipal Water District stopped pumping water from Lake Texoma in 2009 because of a zebra mussel infestation and is building a 46-mile pipeline extension that carries water directly from Texoma to a treatment plant at Lake Lavon.
Prior to Ray Roberts Lake, Lake Texoma and Sister Grove Creek had been the only bodies of water in Texas where zebra mussel colonies had been found. A lone adult zebra mussel was found in Lake Ray Hubbard in May 2011.
PEGGY HEINKEL-WOLFE can be reached at 940-566-6881. Her e-mail address is pheinkel-wolfe@dentonrc.com .
DAWN COBB can be reached at 940-566-6879. Her e-mail address is dcobb@dentonrc.com .




