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Boat Inspection
Boat Inspection

​ANS ALERT: Monitoring finds Evidence of Quagga Mussel Larvae in Green Mountain Reservoir

State and federal officials have confirmed the presence of invasive quagga mussel larvae, known as veligers, in Green Mountain Reservoir​.

On Aug. 18, as part of a state and federal initiative to monitor aquatic nuisance species (ANS) in the state, specialists with the U.S. Bureau of Reclamation first confirmed the presence of the veligers, initially through microscopic analysis followed by DNA testing. An independent laboratory contracted by Colorado Parks and Wildlife confirmed Reclamation's findings. It is unknown if the veligers were dead or alive at the time of detection. For more information, please see the press release​

What does this mean for boaters?​

  • Boats entering Green Mountain Reservoir will continue to inspected prior to entry to prevent further introductions of mussels into the reservoir.

  • Boats at Green Mountain Reservoir will now receive a high risk inspection after coming off the water. If the boat has ballast tanks, an inboard or an inboard/outboard engine, or can not be fully drained and dried, they will be required to get decontaminated.

  • All boats leaving will get a green seal and blue receipt indicating they were last in Green Mountain Reservoir and have followed proper inspection and decontamination procedures. (White receipts are used at negative waters.) For more information, please see the Boater’s Guide to Aquatic Nuisance Species (ANS) Inspections​.

  • Green Mountain seals and receipts (blue or white) are no longer valid for pre-inspection anywhere in Colorado State Parks.

  • Following the Labor Day weekend, boats will be required to enter and exit the reservoir from the Heeney Marina ramp.  

​For more information on Zebra and Quagga Mussels, please visit the Aquatic Nuisance Species page​.

​​​​​​​​​Help Prevent the Spread of ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Aq​uatic Nuisance SpeciesANS Inspection Brochure cover

Mandatory - This boating season brings with it mandatory state-certified boat inspections to help prevent the spread of zebra and quagga mussels and other aquatic invasive species (AIS) in Colorado lakes and reservoirs. See the List of Statewide Watercraft Inspection and Decontamination Sites​​​​​.

Please read the Boater’s Guide to Aquatic Nuisance Species (ANS) Inspections to speed up your next boat inspection. Also, remember to Clean, D​​rain, and Dry​​ your boat before entering or leaving any waters!

​Resident Boaters

​You must pass a state-certified ​boat inspection if:

  • You have traveled outside of the state to boat.
  • You have launched on any of the Colorado lakes or reservoirs where mussels have been detected. You must submit to an inspection for aquatic nuisance species prior to leaving the body of water.
  • You enter a reservoir where inspections are required.  See the List of Statewide Watercraft Inspection and Decontamination Sites​​​​​​. Boaters should expect to be inspected at any lake or reservoir in the state.

Out-of-State Boaters

You must pass a state-certified boat inspection if you plan on launching in any Colorado lake, reservoir or waterway.

Latest Findings

How to Help Prevent the Spread of Invasive Species

Zebra and quagga mussels are a serious threat to Colorado waters. Invasive species such as the zebra mussel negatively influence the food chain for native fish. Zebra mussels remove major quantities of phytoplankton from the water.  Phytoplankton is food for larval and juvenile fish. To learn more about the negative effects of aquatic nuisance species, visit 100th Meridian Initiative and Protect Your Waters.​

To help prevent the spread of zebra and quagga mussels, boaters should remember to follow these steps: Clean, D​​rain, Dry​.

Check your boat and trailer every time before you transport your boat. Overland transport of boats, motors, trailers and other watercraft poses the greatest risk for spreading zebra and quagga mussels. Adult mussels can attach or “hitchhike” to any surface and can live several days out of water (depending on the time of year) in moist, shaded areas. The microscopic mussel larvae (known as veligers​) can be transferred in water contained in live wells, bilge, ballast tanks or “minnow” buckets. Check out these educational catchy tunes that offer listeners tips on preventing the spread of aquatic invasive species.

To help the Colorado Parks and Wildlife quickly identify new populations of this unwanted species please report any sightings to Elizabeth Brown, Invasive Species Coordinator.

Please contact the Invasive Species Program at 303-291-7295 with any questions about ANS or other invasive species.​