Presentation by Greg Bugbee:
Our speaker for the meeting, Greg Bugbee, is an Associate Scientist at the CT Agricultural Experiment Station (Dept. of Environmental Sciences.) He has lead aquatic plant surveys on over 250 lakes and ponds and has directed research projects on invasive plant control. He also oversees the Agricultural Experiment Station’s soil testing program designed to reduce use of fertilizers in watersheds. Greg and his team studied our lake for 5 ½ months, from May to late September, 2016. He prepared a comprehensive 37-page report for us.
Greg explained that he began working with the lake program in the late 1990s. He stressed the importance of native aquatic plants because they are food and habitat for wildlife, they improve water clarity, remove nutrients, reduce algal blooms and help resist growth of invasive species. He suggests a 20-40% coverage of native aquatic plants. In CT lakes, 2/3 of plants are non-native invasive species.
In May 2016, Mamanasco Lake had excessive growth of non-native invasive curlyleaf pondweed. This dies back naturally but leaves biomass on the lake bottom. In the spring, we also had the native plants coontail, waterlily, common reed, pickerel weed, small pondweed and homed pondweed.
In late summer 2016, in addition to the above plants, the lake also had common duckweed, minor naiad, great duckweed and watermeal. In late summer the lake also had a large filamentous algal bloom. The lake had large patches of invasive minor naiad, an increase in coontail and a decrease in small pondweed.
Water Chemistry was measured at the inlet near Al Marcus’ house and at the outlet at the spillway. Total phosphorus (P) measured 67 at the inlet and 73 at the outlet. Generally the outlet stream had lower P concentrations than at the inlet. A number over 20 indicates too much P which encourages nuisance algae bloom. The mean monthly P concentration ranged from 18-34 at the surface and 14-97 at the bottom. Phosphorus counts over 50 are categorized as hypereutrophic. The water at the bottom of the lake had very high phosphorus count.
Water Clarity is measured with a Secchi Disk. The mean water clarity was 1.9 and range from 1.2 to 2.3 (can see the disc through the water at the depth of 2.3 feet.) Clarity was good in May, June and September but low in August..
Alkalinity: Our lake has an extremely high Ph with mean Ph ranging from 66-89. The state lake average is 10. Plants that grow well with high alkalinity are Asian watermilfoil, curly leaf pondweed and minor naiad – all of which we have. High PH also supports zebra mussels which we do not yet have.
* Best option is to deepen the lake by dredging although this is usually prohibitively expensive.
* Treat curlyleaf pondweed early, in mid-April, to interrupt their life cycle and reduce the yearly increase in biomass. There is a correlation between biomass of curlyleaf pondweed and Lyngbya/Microseira wollei (algae mats.) these type of algae mats are nearly impervious to most algaecides.
* Can use Phoslock which binds P very well but very expensive.
* Grass carp are not likely to control the algal mat problem and can promote them by releasing nutrients formerly tied up by vegetation.
* Buffer zones around lake prevent more nutrients from entering the lake.
* Pond and Lake Connection is in contact with a Wisconsin company, Aquafix, which is using enzymes and microbes to disrupt algae growth.
When asked about the frequency of repeat studies of the lake, Greg Bugbee recommended every five years.
Greg Bugbee was thanked for his work and his presentation. Our representatives from Pond and Lake Connection were also thanked for their input.
The Board members were introduced and the work they do to preserve the lake, as well as other off-board community members who assist.
Recap of MLIF work in 2016
* The lake was open all summer with no blue-green algae.
* MLIF received a $10,000 grant from the Anne Richardson Fund for the lake survey and removal of dead and dying tree from the lake. The lake survey was conducted by the CT Dept. of Environmental Sciences Agriculture Experiment Station as reported above.
* The Stormwater Drainage Project at the Third Lane stream was completed by the town. This stream had eroded over time forming a canyon and pushing huge amounts of silt and dirt into the lake.
* Attendance at the CT Lakes conference April 9.
* A letter to the state regarding treatment permit delays and an assist from State Senator Toni Boucher brought a positive response with permits expected by April 1.
Plans for 2017
* Incorporate Greg Bugbee’s findings into lake management plans
* Applied for three-year treatment permit to avoid future delays
* Finish Richardson Grant project of removal of dead trees from lake
* Educate watershed property owners via emails and mailings. Continuing efforts to reduce use of fertilizer in the watershed.
* Encourage attendance at the CT Lakes Conference in New Haven on April 29
* Apply for future grants
Nominating Committee Report:
Mimi Dalbey, Chair, presented the report from the Nominating Committee. The Committee included off-board members Elsa George and Michael Juliano. Mimi presented their proposed slate of officers and directors. Kitty moved, and Mimi seconded, a motion to approve the slate of officers and directors for 2017 as presented by the Nominating Committee. Hearing no discussion the motion was unanimously approved.
MLIF 2017 Officers and Directors:
MLIF Consultants to the Board: Bernie Cassidy, Tessa Jucaite, Jeff McAllister, Mark Zeck