Green Mountain Reservoir prone to invasive species invasion |

Green Mountain Reservoir prone to invasive species invasion

Boats that have been in out-of-state waters and then come to Colorado to launch increase the risk of aquatic nuisance species infestation due to potential mussel encrustation. “It’s a real threat,” says Colorado Parks and Wildlife invasive species specialist Robert Walters.
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There’s a hidden menace always lurking each year just as Colorado’s lakes reopen for boating and other summer activities. But, unlike the Loch Ness Monster, this invasive species doesn’t sell T-shirts and won’t attract tourists. The impacts of this scourge can be significant and expensive.

With boating season poised to kick off on Memorial Day weekend, it’s time to become vigilant over aquatic nuisance species — ANS, for short. These non-native troublemakers often physically change local ecosystems by altering traditional food chains, damage water infrastructure and degrade water quality, as well as limit fishing and recreational opportunities.

In Colorado, the main threat is zebra and quagga mussels, two freshwater species that are closely related and originated in Western Europe and Eastern Asia. These critters seek out dark and discreet crevices and clefts and fasten themselves to the underside of boats for protection.

Last year was a record year in the state for the number of boats found to possess these mussels by Colorado Parks and Wildlife (CPW), the agency charged with most recreation, fish and wildlife management. By this same time in 2015, inspectors discovered three boats with the nuisance species and pinpointed 24 by the end of the season.

“It’s a real threat,” said Robert Walters, invasive species specialist for CPW. “In 2016, we’ve already intercepted five watercraft coming into the state with confirmed zebra and quagga mussels, so we’re on pace to exceed what we did last year.”

This particular invasive species removes major quantities of plankton, which act as food for juvenile fish, and other nutrients from the water. On top of that, if zebra and quagga mussels then go undetected and a boat encrusted with them launches into a different body of water and unintentionally transfers them, it is practically impossible to remove them permanently once they occupy it.

At many well-attended boating spots throughout the state, CPW relies exclusively on boater education programs through prevention campaigns and instructive signage to offset ANS issues. There are other locations, though, that are considered high-priority or high-risk due to their proximity to the Front Range.

On the White River National Forest, there are just three reservoirs that are considered at heightened risk from these invasive species entering the water from boaters. Those are Dillon Reservoir, Ruedi Reservoir near Basalt in the Aspen-Sopris Ranger District and the Green Mountain Reservoir on the northern end of Summit County along the Blue River.

Denver Water, which manages Dillon Reservoir, pays for boat inspectors before vessels launch if they’ve been out of state or for residents if they’ve been in local, known infected water. Inspectors at the Ruedi and Green Mountain have in the past been financed by a combination of U.S. Forest Service regional dollars that get split up among the many districts, in addition to CPW funding.

But, as annual Forest Service budgets continue to dwindle — the White River had a general allocation of $31 million five years ago and for 2016 is operating on just $18 million — the local districts have had to make difficult choices and purge maintaining reserves for nonessential programs such as invasive species prevention. The Ruedi still has some funding streams to keep its program running, but Green Mountain has been less fortunate.

“As we’ve declined in our funding, we’ve had to prioritize what we do at the forest level,” said Bill Jackson, Dillon district ranger. “So what do we fund — seasonal employees, people, other programs or (invasive species)? Those are tough decisions to make, and some people think (infestation) is inevitable or don’t think that it’s money well spent.”

The predicament is, however, that without proper prevention measures, the cost of potential mussel contamination can be much, much higher. On some multiuse reservoirs around the country — Green Mountain is also the location of the Green Mountain Dam — maintenance can skyrocket where these problem species land because they can cause water treatment, irrigation and power generation facility snags.

“If there were quagga and zebra mussels in there,” said County Commissioner Karn Stiegelmeier, “it would cost millions and millions of dollars annually. There is a huge, very expensive problem with them in Lake Powell, for instance, and a lot of Arizona reservoirs.”

The Great Lakes, infested with zebra and quagga mussels, are a primary example. A study from the late-1990s showed astounding numbers regarding the true cost of the pest. During a six-year period from 1993-99, estimates stated that local energy companies lost more than $3 billion because of the mussel problems. As area boaters head to Lake Powell and Meade, which both contain these mussels, and return to Colorado, worries remain.

Pueblo Reservoir is the only one in the state known to have the quagga mussel, though those spotted have only been in a developmental larval stage known as a veliger. While not yet pervasive, the goal remains to avert this problem in other favorite, yet susceptible, sites for boating such as Green Mountain.

“It’s just the veligers that have been detected,” Mike Porras, CPW’s public information officer, said of Pueblo Reservoir. “The inspections are critical to help keep our waters from becoming infested.”

Stiegelmeier, along with the Dillon Ranger District and CPW, are optimistic they can locate the necessary dollars to keep up mandatory inspections before boats launch into Green Mountain Reservoir. They are looking to the Bureau of Reclamation, which owns and manages the dam there, to take on the burden of these costs, while also still searching for other proceeds.

“We are doing our best to find money for these programs,” said Jackson. “If the funding doesn’t come through, then, like other locations, we’ll have to rely on educating boaters, signs and really getting the word out through websites and social media. Otherwise, we’ll just have to close the area to boating, and we don’t want to do that.

“We haven’t given up and we’re still beating the bushes for help,” he added, “and still looking at options here in Summit County. We’re doing what we can.”

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