Glen Lake Association launches treatment to eradicate Invasive Eurasian Watermilfoil
From staff reports
This summer, the Glen Lake Association, in collaboration with the Grand Traverse Band of Ottawa and Chippewa Indians (GTB), will deploy a targeted, nonchemical treatment to eradicate three colonies of invasive Eurasian watermilfoil, or EWM, discovered in the deep basin of Little Glen Lake last year. These efforts aim to protect Glen Lake’s ecological integrity by preventing the spread of EWM and supporting the return of native plant species to affected areas.
The infestation will be addressed using burlap benthic barriers, a method recently refined by the GTB and the Lake Leelanau Lake Association through successful deployments on Lake Leelanau. Scuba divers will install biodegradable barriers over known EWM stands, and the site will continue to be monitored until the species is eradicated.
“Collaboration is key when it comes to protecting our lakes,” said Rob Karner, Watershed Biologist for the Glen Lake Association. “Thanks to early detection and a rapid, science-based response, we have a real opportunity to stop this infestation before it becomes a long-term problem. Early intervention is essential, and this is exactly the kind of coordinated effort that can make it possible.”
GLA will continue surveying for EWM this summer using drone and underwater ROV technology, with priority areas including Big Glen, Brooks Lake, and Fisher Lakes.
The treatment is expected to begin June 21, with timing dependent on weather conditions. During and after deployment, treatment zones in Little Glen will be marked with buoys and floating flags. The GLA urges all lake users to avoid these areas to protect the treatment site and to always “clean, drain, and dry” boats, trailers, and gear before launching into a new waterbody. The GLA offers a free, hot water boat wash at 7075 W. Day Forest Rd. to prevent invasive species from entering the lake. The GLA Boat Wash is open and staffed seven days a week from 6 a.m. to 7 p.m.
“Disturbance from anchors or boat activity could compromise the treatment and may unintentionally spread EWM. We’re asking all boaters to be mindful and avoid the clearly marked areas as they recreate this summer and to always clean their watercrafts when visiting from other lakes,” said Kate Gille, Executive Director of the Glen Lake Association. “Everyone who enjoys these waters has a role to play in keeping them healthy and beautiful.”
About the Glen Lake Association
Founded in 1945, the Glen Lake Association is a nonprofit organization dedicated to the preservation and protection of the Glen Lake/Crystal River Watershed. Through science-based strategies and partnerships with government and non-government organizations, the association works to protect water quality across the 46-square-mile watershed while advancing environmental education, promoting sustainable policies, and enhancing quality of life. For more information, visit GlenLakeAssociation.org.
Above: A satellite image of Little Glen Lake in Glen Arbor, Mich., shows the locations of three Eurasian watermilfoil treatment sites, marked with red arrows. The Glen Lake Association, in collaboration with the Grand Traverse Band of Ottawa and Chippewa Indians, will install biodegradable burlap benthic barriers at these sites in summer 2025 as part of a nonchemical effort to control the invasive species. (Image courtesy of Glen Lake Association)
