A pesky mussel that invaded Lake Mead in 2007 might have spread to two reservoirs in Northern Nevada.
Rye Patch Reservoir south of Winnemucca and Lahontan Reservoir west of Fallon have tested positive for the presence of quagga mussels, a state wildlife official confirmed Wednesday.
Follow-up tests are under way, with results expected sometime next week, said Doug Nielsen, spokesman for the Nevada Department of Wildlife.
If confirmed, it would mark the first discovery of quaggas in Nevada outside of the Colorado River system.
Each mussel is usually no bigger than a man's thumbnail, but their dense and fast-growing colonies have caused billions of dollars in damage and preventive maintenance costs in the Great Lakes region and elsewhere in the Midwest and eastern United States.
Left unchecked, quaggas can clog water pipelines, power plant cooling systems and marine equipment. They can completely plug a pipe up to 12 inches in diameter and restrict flow in larger pipes. Their colonies also are known to speed the corrosion of underwater infrastructure.
Until January 2007, when they turned up in Lake Mead, quagga mussels had never been found west of the Mississippi River. Since then, the bivalve mollusk with the striped shell has turned up in lakes Mohave and Havasu downstream from Hoover Dam and in water systems in California and Arizona.
If quaggas are confirmed in Rye Patch or Lahontan reservoirs, Nielsen said, they most likely got there by hitching a ride on someone's boat or boating equipment.
Under the right conditions, the mussels can be spread on life jackets, waders, swimsuits or even on the bumper of a car that is backed into the water to drop off a boat.
"Our message to all recreationists is clean, drain and dry your equipment," Nielsen said.
Just to be safe, he said, recreationists should use soap and hot water and then leave the equipment out to dry for at least five days in the summer heat.