SALT LAKE CITY — State wildlife officials are fearful that quagga mussels may have made their way into the waters of Deer Creek Reservoir and are ordering that boats leaving the lake be decontaminated immediately.
DNA tests conduced by two laboratories found microscopic juvenile quagga mussels — called veligers — in a water sample taken from the reservoir.
The discovery, however, does not necessarily mean Deer Creek Reservoir is infested with the invasive mussels.
"We've found veligers in the past at other waters in Utah," said Jordan Nielson, aquatic invasive species coordinator for the Utah Division of Wildlife Resources. "With the exception of Lake Powell, mussel populations never established themselves in the waters where veligers were found. We're hoping that will be the case at Deer Creek, too."
The confirmed presence of the juvenile mussels has far-reaching implications and potentially millions of dollars in costs because of Deer Creek Reservoir's intricate role in the water delivery system for more than a half-million people in Utah and Salt Lake counties.
Quagga mussels attach themselves to pipelines, water intake valves and other structures, leading to clogs and equipment failures in everything from boat propellers to sophisticated water delivery systems.
"The invasiveness of this is just beyond belief," said Sen. Scott Jenkins, R-Plain City. "They destroy the fishery, they destroy the sandy beaches, they destroy anything mechanical they attach to. It's just a nightmare what they do."
Nielson said the juvenile mussels were discovered through routine monitoring conducted on major water bodies across the state. The division is involved in sampling at a minimum of once a year, and the U.S. Bureau of Reclamation monitors as well. So far, Lake Powell is the only water body in the state of Utah to be overcome by the quagga, though other major lakes along the lower Colorado River system are infected as well, including Lake Havasu and Lake Mead.
The monitoring at Deer Creek will now take place for a minimum of three years, he added.
We've found veligers in the past at other waters in Utah. With the exception of Lake Powell, mussel populations never established themselves in the waters where veligers were found. We're hoping that will be the case at Deer Creek, too.
"And if we find something, we want to act on it extremely quickly," Nielson said.
Quagga mussels usually do not reproduce in water colder than 50 degrees, so there's little risk at present for any adults that may be present to reproduce, he said. That could change once the water starts to warm up in the spring.
Nielson says the presence of veligers in the reservoir does not mean a quagga mussel population has established itself there.
"To establish itself," he said, "a quagga population needs adult mussels."
Nielson added that it could be that the young mussels made their way into the reservoir via transport on a boat that came from contaminated water — something that can only be determined with additional surveying to be conducted in the spring.
The division, along with the Utah Division of Parks and Recreation and the U.S. Bureau of Reclamation, will collect more water samples for analysis, send divers into the water to search for mussels, and place devices in the water that encourage adult quagga mussel attachment. The investigation will also include shoreline sampling, as well as looking downstream along the Provo River to determine any issues there.
To prevent further potential spread of the devastating mussels, the division is ordering the immediate decontamination of any boat leaving Deer Creek.
- Clean and drain their boat, on their own. After cleaning and draining, a division or Utah state park technician will place a tag on the boat that indicates when it was cleaned and drained. The boat will not be allowed to launch at another body of water in Utah until the boat has dried long enough to kill any mussels that might be in or on it.
- Ensure their boats are dry for at least 30 days. The drying time can be as little as three days, however, if the temperature the boat is drying in remains below freezing for at least 72 straight hours.
- Or have their boat professionally decontaminated. The service is free.