Federal, state, local authorities work together to avoid catastrophe at Green Mountain Reservoir

A head of Northern Pike fish is seen at Green Mountain Reservoir on June 10, 2017. Feds, state, and local authorities are teaming up to stop a potential quagga mussel infestation that can destroy the lake's ecosystem.
Hugh Carey / |

Wanted: A striped alien mussel about the size of a human fingernail. Goes by the name of “Quagga.” Able to lay a million eggs in a single year. Last seen hiding inside boat motors, hitchhiking on fiberglass hulls and feeding at the bottom of water bodies across North America.

Its crime: Ravaging aquatic ecosystems, damaging dams and other water infrastructure, ruining recreational fishing. If seen, contact Colorado Parks and Wildlife immediately.

While wanted posters for the quagga mussel are not literally going up along the shores of Green Mountain Reservoir, they might as well be for all the effort devoted to hunting it since signs of the mollusk were detected there last summer. Should the non-native quaggas infest the reservoir, millions in taxpayer money will be spent to ensure they do not clog or damage water infrastructure, as well as to prevent destruction of the aquatic ecosystem and the associated recreational fishing industry.

The danger posed by this critter is so high that Colorado Parks and Wildlife, the U.S. Forest Service, the Bureau of Reclamation, Summit County and other agencies are combining efforts to make sure the quagga does not wind up ruining the reservoir as it has other water bodies in Colorado.

Legislatively, a bill called the “Mussel-Free Colorado Act” dedicated to eradicating quagga and zebra mussels is well on its way to becoming state law. The bill requires boat owners to purchase an aquatic invasive species sticker on top of their regular boat registration to fund mussel prevention measures.

County Commissioner Karn Stiegelmeier has been following developments at the reservoir intently since last August, when the Bureau of Reclamation discovered quagga veliger, or larvae, in the reservoir. At the time, Stiegelmeier said she was furious with the lack of federal funding to pay for boat inspections preventing mussel infestation in the first place.

“Other reservoirs like Dillon Dam and Wolford are taken care of by the responsible dam owners,” Stiegelmeier said. “They pay for regular boat inspections before they get in the water, as they should. But the federal government reservoirs always contract out recreation and claim it’s not their job to making sure boats aren’t contaminated before they launch.”


Federal authorities were put on high alert and finally turned their attention to Green Mountain once mussel larvae was detected. Stiegelmeier said that it will be a much more expensive endeavor to try to ward off infestation after it starts.

“Once a reservoir is infested, the feds wind up having to pay many times as much to deal with the infestation,” she said. “Once the adult mussels get in there you can’t get rid of them. We have a huge number of reservoirs, like Lake Powell, that are infested. It costs an enormous amount of money to get mussels off the dam infrastructure, and it absolutely destroys the aquatic ecosystem.”

While samples at Green Mountain have come back clean since the initial detection, Bill Jackson, head of the U.S. Forest Service’s Dillon Ranger District, said that concern over quagga is far from over.

“We haven’t detected it since, but that doesn’t get us out of the woods yet,” Jackson said. “We need three years of sampling before declaring a water body mussel-free.”

Jackson recalls hearing of another body of water that similarly had no larvae detection for over a year, but then reappeared well after the one-year mark.

“Not a lot of people understand that even with negative samples you might still have something lurking there,” he said.

Constant monitoring for larvae is of paramount importance, Jackson said. If mussels mature in a water body, the spread can be unstoppable.

“Once quagga gains a foothold in a water body, they reproduce in the millions,” Jackson said. “They quickly latch on to whatever they can latch on to. It can be a steel structure, a boat motor, dam infrastructure or water pipes and water works and cause massive damage. They can also attach on to native species and hurt their survival.”

Once the adult mussels take root, they can wreak havoc on a water body’s fragile ecosystem and disrupt the food chain.

“They’re a filter feed species, which means they suck in water and eat all the nutrients,” Jackson explained. “If you have enough of them, they essentially consume all the nutrients in the water. This can leave water bodies sterile, leaving no food for other aquatic species in lake. That seriously affects the water, which then in turn has an effect on all the native fish and insects.”

Jackson said that to prevent the infestation, the Forest Service and other agencies will monitor water at Green Mountain for at least three years — the maximum amount of time quagga need to fully develop. The agencies are also working to divert all incoming boat traffic to a single launch point at Heeney Marina, where they can be centrally inspected and decontaminated before reaching the water. Jackson said that one major risk factor for contamination was how many boats were previously launched from unauthorized areas along the shoreline.

“We had a lot of motorboat launches into the reservoir without proper inspection and decontamination,” Jackson said. “We’ve really been trying to make sure that we got on that right away to prevent folks from doing that.”

Jackson said that the Northern Colorado Water Conservancy District, which gets some of the water from the reservoir, helped in providing rocks, boulders and other implements to block off the known boat entry points. He also said that signage will be put around the reservoir directing boat owners to proper launch points where they will be inspected and decontaminated before hitting the water.

In the months leading to boating season, Jackson said that a major collaborative project will be taking place to improve the inspection and decontamination process at Green Mountain.

The Bureau of Reclamation and other partners will help Heeney Marina to improve its boat launch facilities and parking to accommodate the large amount of boat traffic being funneled there. The Forest Service will do its part by allowing modifications to the marina’s permit for construction there, as it operates on Forest Service land.

The project will also require Summit County to help by closing down and improving the county roads leading into and out of the reservoir, as well as introducing more signage. Details of the project have yet to be released in full to the public, but Jackson said a press release is forthcoming.

Jackson added that they needed the public’s help in preventing contamination.

“If folks are not getting their boats inspected, that doesn’t help anyone, and we wind up dealing with the aftermath of cleanup efforts. Prevention is where we want to be.”

Jackson said that boat owners can help by following a three part procedure: Clean, drain and dry.

“Make sure to clean your boat – remove plants and mud from water craft before every launch, as mussels can attach to them,” Jackson said. “Drain all the water compartments and engines, especially if you have an inboard motor. Make sure when you go from lake to another, make sure you’re not carrying water.

“Finally, dry your boat. Make sure that your boat is completely dry between uses. Mussels thrive in wet environments. Make sure those little crevices are completely dry and free of debris.”

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