Songo River story Part 1:
Songo River story Part 2:
The Songo River and Brandy Pond are among Maine’s busiest waterways. They act as the corridor between a milfoil infested Sebago Lake and the vulnerable Long Lake. Both Sebago and Long Lake are among the state’s most attractive boating destinations. In 2012 more than 3,700 boaters passed through the Songo Lock and another 1,700 Entered the Songo River at the Sebago Lake State Park boat launch.
Variable leaf milfoil was documented in a 2003 survey of the Songo River by LEA, which developed a comprehensive plan to combat the infestation. An unknown infestation was then discovered in Brandy Pond in 2004. Some of the plant beds rose to the surface and looked dense enough to walk on. When LEA began work, there were about three acres of variable leaf milfoil in the upper river and at one marina in Brandy Pond. Much of the river was heavily infested and the plants were spreading rapidly.
The struggle to control milfoil started on Brandy Pond and continued on the Songo River in 2005. The Libra Foundation awarded LEA a grant to help develop innovative control methods. LEA pioneered the use of blue “Mainer” tarps to tackle the extensive plant beds. The tarps measure 40 feet by 60 feet, allowing LEA to cover substantial areas relatively quickly. Spreading the bottom barriers on the river bottom kills plants by blocking sunlight. When the LEA crew lifted the tarps a barren sandy bottom replaced milfoil growth. The big tarps allowed LEA to get a jump on the infestation and reduce the acreage by about a third.
While we were making dramatic progress along the river, infestations developed at all of the commercial and private marinas on Brandy Pond. It was clear that boats coming up Songo River were the major vector for the plants. LEA staff began routine maintenance work at all of the marinas to prevent numerous small outbreaks from expanding. While the large blue tarps were a great success, bottom barriers were difficult or impossible to use in steep sections of the Songo River or where there is a lot of debris. So LEA contracted a commercial suction harvester who worked on removing plants from the river in June 2006.
By fall, LEA was able to launch its own suction harvester, thanks to the generosity of the Libra Foundation and Jim Fleck of Bridgton, who donated a pontoon boat. A 28-hp pump on the converted pontoon boat draws water from the river through a four-inch hose. A diver gently pulls up a milfoil plant – trying hard to get the entire root system – and sends the plant up the hose. Water and plants are discharged into a sluiceway then diverted into chutes with mesh bags attached. The bags trap plants, but allow water to flow through and drain back into the river.
With a seasoned crew, the S.S. Libra and many tarps, LEA made remarkable progress in 2008 and 2009. In August 2008, Dr. Dan Buckley, of the University of Maine-Farmington, surveyed the upper Songo and reported he “was happily surprised to find that over 99 percent of the infestation that we had seen in 2006 was gone . . . Your efforts and those of your abatement crew have worked wonders.” But as LEA staff and volunteers scoured marinas, shorelines and coves, several new patches of plants were found in Brandy Pond, posing a serious threat to Long Lake. In fall 2009, a new infestation was discovered. DEP divers and LEA staff quickly tarped the area to reduce the threat. After years of work and a total cost of about $250,000, LEA finally thought the infestation was under control in 2009.
The long hot summer of 2010 resulted in the worst infestation ever on the lower Songo River and high traffic through Songo Lock posed an extreme threat to the upper Songo, Brandy Pond and Long Lake. The lower Songo, from Sebago Lake State Park to Songo Lock, is heavily infested and is one of the busiest waterways in Maine. After inspectors found many boats in the lock carrying milfoil fragments and many more fragments floating in the water, LEA asked the state to close the Songo Lock. But the process, which involved several state agencies, proved complicated and time-consuming.
The lock remained open, but the Maine Department of Environmental Protection funded increased boat inspections there and continued to do so in 2011. The Department of Conservation marked the lower Songo with new navigational buoys to help boaters avoid the most infested areas. To minimize the risk this, LEA has renewed its plea that boaters not travel upstream through the lock. The more boats traveling through the lock, the higher the risk that one or more will carry milfoil into the upper Songo, Brandy Pond or Long Lake. It’s very difficult to inspect boats in the crowded lock and even a one-inch fragment can root and spread the infestation, which could have a severe impact on the Lake Region’s economy.
The first survey of Brandy Pond and the upper Songo in June 2011 revealed only a few dozen plants. When the team started its work years earlier, there were three acres of plants. By the time the LEA crew disbanded in August, the 800-foot safety zone below the lock had been cleared, as had the Upper Songo River, Brandy Pond, and Crooked River. This was made possible because of the great work the LEA Milfoil Team had done over the past five years. They did not achieve total eradication, as some plants will re-generate, but we expect the task will be significantly easier in the coming years.