Zebra mussels confirmed in Grand Lake in Stearns County

June 13, 2022


The Minnesota Department of Natural Resources has confirmed a report of zebra mussels in Grand Lake, just south of Rockville in Stearns County.

The Grand Lake Improvement District contacted the DNR about three adult zebra mussels found by lake users on the north and northeast shorelines. DNR staff conducted a search of the lake and found an additional 11 adult zebra mussels distributed throughout the 650-acre lake.

Whether or not a lake has any invasive species, Minnesota law requires people to:

  • Clean watercraft, trailers and equipment to remove aquatic plants and prohibited invasive species.
  • Drain all water and leave drain plugs out during transport.
  • Dispose of unwanted bait in the trash.
  • Never release bait, plants or aquarium pets into Minnesota waters.
  • Dry docks, lifts and rafts for 21 days before moving them from one water body to another.

These additional steps reduce the risk of spreading aquatic invasive species:

  • Decontaminate watercraft and equipment – find free stations on the courtesy decontamination page of the DNR website.
  • Spray with high-pressure water or rinse with very hot water (120 degrees for at least two minutes or 140 degrees for at least 10 seconds).
  • Dry watercraft and equipment for at least five days before using in another water body.

Zebra mussels can compete with native species for food and habitat, cut the feet of swimmers, reduce the performance of boat motors, and cause expensive damage to water intake pipes.

People should contact a Minnesota DNR aquatic invasive species specialist if they think they have found zebra mussels or any other invasive species.

More information is available on the aquatic invasive species page of the DNR website.