News Release

Zebra mussels confirmed in Lake Riley, Carver County

October 29, 2018

Fall is a key time of year to check for invasive species

The Minnesota Department of Natural Resources has confirmed zebra mussels in Lake Riley in Carver County. 

A lake service provider business contacted the DNR after finding juvenile zebra mussels on docks and lifts they were removing from the lake for the season. Riley Purgatory Bluff Creek Watershed District staff searched five locations around the perimeter of the lake and found zebra mussels at every site. They recorded a total of 91 zebra mussels on a variety of surfaces around the lake.

"It helps a lot when lake property owners, lake service businesses and others notify us when they’ve spotted an invasive species," said DNR Invasive Species Unit Supervisor Heidi Wolf. "We also appreciate the good work of the Riley Purgatory Bluff Creek Watershed District and their early detection and monitoring program."

Minnesota law requires keeping docks and lifts out of the water for at least 21 days before putting them into another body of water.

The DNR recommends these steps for lake property owners:

  • Look on the posts, wheels and underwater support bars of docks and lifts, as well as any parts of boats, pontoons and rafts that may have been submerged in water for an extended period.
  • Hire DNR-permitted lake service provider businesses to install or remove boats, docks, lifts and other water-related equipment. These businesses have received training on Minnesota’s aquatic invasive species laws and many have experience identifying and removing invasive species.
  • People should contact their area aquatic invasive species specialist if they think they have discovered an invasive species that has not already been confirmed in a lake. Take a photo of any newly discovered invasive species before removing it from equipment. Save specimens or leave them in place until the DNR can investigate.

More information is available at