Lake Colby Association

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Invasives

The Lake Colby milfoil eradication project is one of the earliest and most important demonstration projects for non-chemical control of Eurasian Watermilfoil in the Adirondack Park. 

Lake Colby is a strategic resource that is home to the D.E.C. Environmental Education Camp, the Town of Harrietstown’s Latour Park, the Village of Saranac Lake’s only public swimming facility, several public camp sites, and a DEC boat launch.  The Lake hosts only seven private shoreowners, four of whom use the lake for drinking water, the rest of the Lake (16,000 out of 17,500 feet of shoreline) being either public-use or forever wild lands. 

Due to the low private ownership on the Lake, finding funds for the project to-date has been an ongoing effort.  Thanks to support from shoreowners, the Town of Harrietstown, the Village of Saranac Lake, and the Lake Champlain Basin Program, funds provided through grants from 2002 to 2006 were sufficient to make slow but steady progress, but were insufficient to deliver a final knockout punch to the spreading milfoil.  In 2006 the LCA’s first NYS Invasive Species Eradication Grant allowed the first complete harvesting of the lake. Other lakes with sufficient financial resources to do multi-pass harvesting have demonstrated that Eurasian Water Milfoil (EWM) can be brought under complete control within two to three years if (and only if) consecutive multi-pass harvests are conducted each season, eliminating in-season re-growth and seeding.  

Harvests from 2002 through 2005 removed over 20 wet tons of milfoil in single-pass harvests, but each subsequent season found significant re-growth.  In 2006 diver productivity was more than doubled through the use of a floating compressor system (known colloquially as a “hookah” or SNUBA rig).  This increased productivity was applied in two full passes of the lake, removing more wet tonnage than in the prior four years combined. 

From 2007 we extended this multi-pass approach to five full passes.  The chart below shows results for the 14 years that we have been running this program.  A bag of wet milfoil, the y-axis, weighs approximately 25 pounds.  The 2014-15 Report on water quality and EWM harvest results is linked here.  The 2015 ALAP study results are linked here.  The mid-year 2106 update is also linked here.  2016 Milfoil harvest summary information is linked here.

In addition the 55 existing benthic barriers have been re-set on high-growth areas. 43 of these are 20' x 20' mats and 12 are 12' x 12' mats.  They are re-set each year by our dive team.

Annual EWM Harvest

In 2015 hand harvesting again resulted in a reasonably steady yield (which is good!).  Unfortunately, chloride levels remain high in the lake (see Water Quality) and Recent studies show that road salt damages native plants but ironically Eurasian Watermilfoil thrives in high-chloride solutions, including the brackish waters of the Chesapeake area and in Florida. 

The LCA again applied for and was awarded a Lake Champlain Basin Program Grant for the 2016 season.  We again submitted the 18 letters of support we have received for our program from the village, town, Watershed Institute, Adirondack Medical Center, Historic Saranac Lake, and others in support of our request which is crucial to our continuing the program.

In 2017 the LCA applied for and was awarded a three-year $50,000 matching grant for Eurasian Water Milfoil eradication in the lake.  The award came late in the 2017 harvesting season but an intensive program was begun in late July.  The goal was complete eradication of EWM by year-end 2020.

Unfortunately, Covid-19 cause the 2020 harvest to be cancelled due to a lack of workers.  Plans are to resume the project in 2021 with state approval.

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The Paul Smith’s Watershed Institute has been the primary subcontractor for dive related activities, supplying a dive leader, divers, and surface support.  Volunteers have provided additional surface support, some dive support, milfoil disposal (in an APA-specified composting bin), and materials (e.g., support watercraft).   A five-person professional team (four divers and one surface person) subcontracted from the Paul Smith’s Watershed Institute costs about $1,800 per day.  Thus far, this cost has been over 90% supported by grants and local government support.