On Tuesday, Colorado Parks and Wildlife announced that the agency has concluded samplings effort related to the discovery of zebra mussel veligers in the Colorado River for 2024. Zebra mussels are an invasive species in Colorado and are known to be devastating to aquatic ecosystems and infrastructure.

The testing period included collecting 450 water samples from the Colorado River, Government Highline Canal, James M. Robb State Park, and Highline Lake State Park. Additional testing also took place throughout the Grand Valley region.

No samples detected the presence of additional zebra mussel veligers or adult zebra mussels, after veligers were initially detected in this part of the state in early July. At the time, the discovery was called “devestating.”

“While we have concluded our sampling efforts for the year, our work is not done,” said Robert Walters, Invasive Species Program Manager. “Staff will continue to look for opportunities to educate the public on simple steps to prevent the spread of zebra mussels or any invasive species in Colorado waters.”

Sampling is set to resume in spring of 2025, with increased testing to take place in the Colorado River and Government Highline Canal over the next five years.

Highline Lake at Highline Lake State Park has also been drained as a means of eradicating a zebra mussel population. Draining of the water source was completed on November 18. Highline Lake should be refilled and open to boating at some point during spring of 2025. Strict rules related to inspection and decontamination of boats on this body of water will apply.

Keeping boats clean is crucial for preventing the spread of invasive species, as dirty boats tend to be a key means for these species to jump from one body of water to another.

Find additional information about this update here.