08/06/2026
Hydrilla, an invasive aquatic plant, has returned to Dewey Lake. Kentucky Fish and Wildlife and the U.S. Army Corps of Engineers recently partnered to treat affected areas before the infestation becomes more widespread.
Hydrilla was first found at Dewey Lake in the early 2000s and eventually disappeared, but over the past four years it has returned and expanded into shallow areas of the lake.
During treatment, some people noticed bright-colored water. The color came from a harmless tracer dye used to track water movement and measure treatment effectiveness—it was not the herbicide. All herbicides used are EPA-approved for aquatic use, and there are no restrictions on swimming, fishing, or other recreational activities.
Treatments focused on boat ramps to help keep public access open and reduce the risk of hydrilla spreading to other lakes on boats and trailers. Additional areas with heavy growth were also treated. Treatment is now complete, and crews will continue monitoring the lake.
Note: The third photo was taken at Dewey Lake Marina in 2006 during the previous hydrilla infestation. It is shared to show how quickly this invasive plant can spread and why early management is so important.
