Zebra mussels persist in Western Slope waters despite thousands of boat inspections and decontaminations.

Colorado Parks and Wildlife reported 2025 inspection results showing zebra mussels remain established in multiple Western Slope waterways, including Highline Lake and parts of the Colorado River system, despite 438,272 boat inspections and 30,039 decontaminations. Environmental DNA testing and expanded sampling detected mussels in 136 boats and new infestations in areas like Rifle and Glenwood Canyon. Roadside checks intercepted 60 boats with invasive species. The agency continues promoting cleaning, draining, and drying boats, and plans a new decontamination tank at Highline Lake. New Zealand mudsnails were also found in the Roaring Fork River.