BRIDGTON — Sixty percent of the Songo River in Naples was infested with the aquatic invasive variable-leaf milfoil (Myriophyllum heterophyllum) in 2004. Lake Environmental Association’s Executive Director Peter Lowell describes it as looking like guts in the water.

Variable-leaf milfoil has a thick, reddish stem with whorls of finely-divided leaves and thin, fragile roots. Its main form of reproduction is by fragmentation. It only takes a small piece to begin a new population. Milfoil can negatively impact native species, recreation and even property values around infected waterbodies.

Adam Perron, LEA’s education director and invasive plants program coordinator, works with a crew of interns to eradicate the milfoil. Their work base is the SS Libra, a pontoon boat purchased with grant money from the Libra Foundation. The boat houses a Diver Assisted Suction Harvester.

While underwater, divers harvest milfoil by the roots and feed the material into the suction hose. Aboard the Libra, roots, stems and leaves are then processed in its sluiceway, which bags the plant material.

For smaller infestations, they remove plants by hand, placing the plant material in dive bags. Once harvested, the milfoil gets composted away from the water.

In some infested areas, the crew also uses benthic barriers to smother the invasive plant. This activity requires permits from Maine’s Department of Environmental Protection.


Throughout the 2015 season, Perron says the crew surveyed areas where they had previously removed plants and found sparse milfoil regrowth.

Lowell says he never thought the river would be as clean as it is today. “We know now that we can control (milfoil),” he says.

Perron states, “For 2016, the river won’t need us much. We’ll be here, but in an increasingly diminished capacity.”

This is only one of LEA’s initiatives.

For the past 44 years, the organization have tested 38 lakes and ponds in the Upper Sebago Lake watershed to create profiles of oxygen, temperature, phosphorus, chlorophyl, conductivity and pH balance.

With this historic baseline, LEA is now ready to develop ways to respond to waterbodies’ needs.


Times are changing, and sadly, the lakes are changing with them.

Lowell says, “It’s time to move beyond doing the same work that’s been done since 1970.”

This past year, LEA’s board of directors approved the creation of the Maine Lake Science Center using existing infrastructure located adjacent to Pondicherry Park in Bridgton.

Dr. Bridie McGreavy, the consulting executive director of the MLSC explains that the center started with the idea of developing different types of research partnerships, including hiring research fellow Amanda Pratt to monitor for the potentially toxic algae Gloeotrichia in a collaborative effort with Bates College; installing HOBO temperature sensors on various lakes in conjunction with the University of Maine at Farmington; and teaming with Colby College to launch the GLEON Buoy that collects a variety of data on Highland Lake.

A Lakes Science Advisory Board comprised of university and interdisciplinary lake research experts was formed several years ago to determine the questions that need to be answered. The science will inform a new set of land-use standards.

LEA has had a long tradition of educating students and citizens to safeguard our natural resources and local economies. Now it is time to develop solutions in collaboration with others in order to make our lakes sustainable.

Leigh Macmillen Hayes is a member of the Lakes Environmental Association Board of Directors. For more information about LEA, contact

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