HEBER CITY — Starting immediately, you must decontaminate your boat before you leave Deer Creek Reservoir in north-central Utah.
The requirement comes after DNA tests conducted by two laboratories found microscopic juvenile quagga mussels — called veligers — in a water sample taken at the reservoir.
Jordan Nielson, aquatic invasive species coordinator for the Division of Wildlife Resources, says the discovery does not mean Deer Creek Reservoir is infested with quagga mussels.
"We've found veligers in the past at other waters in Utah," he says. "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."
Nielson says quagga mussels usually do not reproduce in water that's colder than 50 degrees, so — even if there are adult mussels in the reservoir — there's currently little risk of the population expanding. That could change, though, once the water starts to warm in the spring.
One item biologists and water managers are concerned about now is mussels being carried to other waters in or on boats. That's why DWR Director Greg Sheehan signed an order on Jan. 15 that requires boats to be decontaminated before leaving Deer Creek State Park. Upon leaving the park, boaters must do one of two things:
- Clean and drain their boat, on their own. After cleaning and draining, a DWR 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.In the winter, boats must dry for at least 30 days. The drying time can be as little as three days, though, if the temperature the boat is drying in remains below 32 degrees Fahrenheit for at least 72 straight hours.
- Have their boat professionally decontaminated. The service is free.A DWR or Utah State Parks technician will determine whether the boat needs to be professionally decontaminated.
Which raises a question: if there aren't any adult mussels in the reservoir, where did the juvenile mussels come from?
"This could be an isolated incident," Nielson says. "For example, it's possible that the veligers made their way to the reservoir in or on a boat that had been on a contaminated water. We'll know a lot more after we and our partners conduct further surveys this spring."
This spring, the DWR and its partners, including Utah State Parks and the Bureau of Reclamation, will take action to learn whether adult quagga mussels are in the reservoir. That action includes:
- Collecting and analyzing water samples.
- Sending divers into the reservoir, to search for mussels.
- Placing substrate samplers in the water. Adult quaggas attach to these as they move through the water.
- Surveying shorelines.
Starting this spring, biologists will also sample the lower Provo River.
Nielson says the middle Provo River, the section between Jordanelle and Deer Creek reservoirs, is less at risk. "Quaggas can't move upstream," he says. "The only way they could make their way to the middle Provo River is if they were transported there on someone's boots or fishing equipment."
Veliger discovery at Deer Creek Reservoir
Two independent tests
On Oct. 30, 2014, a Bureau of Reclamation (BOR) water quality sampling crew collected water samples across Deer Creek. The water samples were later analyzed by a BOR lab.
On Dec. 12, lab technicians, looking through a microscope, found what appeared to be five quagga mussel veligers in a sample taken near the dam. The DWR requested that the samples be genetically analyzed to learn whether they were in fact quagga mussels. Through DNA testing, both the BOR lab and Pisces Molecular, a private third party, confirmed that the veligers were quagga mussels.
Where did they come from?
Nielson says it's impossible to know where the veligers came from. "The lower end of Lake Powell," he says, "as well as other reservoirs on the lower Colorado River, have a rapidly growing population of quagga mussels. It's possible that someone who was boating on a lake with quagga mussels accidentally brought the veligers to Deer Creek. We'll never know for sure."
Why the concern?
If a quagga mussel population establishes itself in Deer Creek Reservoir, residents in Salt Lake County and Utah County, as well as anglers and those who enjoy recreating at the reservoir, have plenty of reasons to be concerned. For example, quagga mussels can:
- clog pipes that deliver water. The cost to remove the mussels could cost water users in Salt Lake County and Utah County millions of dollars.
- filter tiny organisms, such as zooplankton, out of the water. Fish rely on these organisms for food. A quagga mussel infestation could affect fish populations in the reservoir, which in turn would affect fishing.
- form massive colonies on popular shoreline areas. The mussels smell bad and can cut your feet when you walk on them.
- clog your boat's cooling system. This can cause your boat to overheat, leading to costly repairs.
Nielson says you must do the following after leaving a quagga-infested water such as Lake Powell, or any body of water in Utah:
- Clean, drain and dry your boat. You can see how to do this at stdofthesea.com.
- Have DWR or Utah State Parks personnel decontaminate your boat. The decontamination is free. You can find the closest unit by visiting stdofthesea.com. At the site, you'll find contact information for the DWR aquatic invasive species biologist in your region. The biologist can direct you to the nearest decontamination unit.