Main Content

Invasive Species

Lake Josephine was diagnosed with an aggressive invasion of Eurasian Water Milfoil in late 2012. Eurasian Water Milfoil (EWM), is a contamination that cannot be eradicated, and requires aggressive and ongoing treatment to control. Left unchecked, it can overtake a lake, making it unnavigable by boats and unsafe for swimming and water sports.

Minnetonka Bay Choked by EWM

Minnetonka Bay Choked by EWM

As an example, Lake Minnetonka has also had significant problems with EWM. It was first found in 1996 in one bay, which was nearly choked out. Thereafter, it spread to multiple parts of the lake, impacting swimming and boating. Two drownings were attributed to the weed infestation. One victim was a member of the U of M swim team, who was training in the lake. Lakeshore property owners in impacted areas saw their home values plummet 30-50%. Each spring through Fall, lake residents have two harvesters operating full-time to try to remove the weeds, at a cost of $200,000.


EWM Lake Jo Algae Lake Jo

A picture paints a thousand words. The pictures were taken in May of 2015 on Lake Josephine, showing how aggressive our EWM and Filamentous Algae infestations were in their early stages. Below are some links with more information concerning Aquatic Invasive Specifies:

MN DNR Aquatic Invasive Species Program

MN DNR Page of Minnesota Aquatic Invasive Animals

MN DNR Page of Minnesota Aquatic Invasive Diseases

MN DNR List of Infested Waters

MN DNR Approved Commercial Aquatic Pesticide Applicators and Mechanical Control Companies