LWFT 2013 Annual Report

2013 Annual Report: Clarifying Strategies and a Gathering Storm

The 2013 Annual Summary Report to the Task Force was prepared by the LWTF limnologist and chief scientific advisor Dr. Robert Kortmann and delivered on March 20, 2014.

The report suggests a course adjustment for LWTF priorities with respect to phosphorus and water clarity, and provides some positive feedback on relatively new in-lake strategies during spring and fall. In addition, it focuses our attention on an evolving threat which has affected other lakes in the region and has drawn increased scrutiny from the scientific community and the state: the release of toxins during the die-off stage of cyanobacteria (often called blue-green algae).

Water clarity and reduced concentrations of phosphorus have exhibited a close correlation over the years, in Lake Waramaug (see charts, right) and elsewhere. Trend lines for these measurements (Secchi disc readings and Total Surface Phosphorus) have, despite occasional anomalies, shown steady improvement and have provided the Task Force with the best testimony to the success of our work. However there has been a subtle shift in emphasis from maximizing to optimizing water clarity. It is believed that maintaining water clarity at a level of 6 to 8 feet (one-half the thickness of the epilimnion, or top warm thermal layer) is ideal for recreational lake activities and transmits some needed light to the metalimnion (mid-level) while providing a less suitable environment for algae and some non-native invasive plants.

Recent experimentation with early spring and fall activation of the in-lake layer aeration systems have shown positive results. In the spring, water circulation is used to enhance the diatom habitat. This may actually sacrifice some clarity temporarily, while delaying and reducing the growth of blue-green algae (cyanobacteria) later in the season. In the fall, layer aeration is used to take iron from the hypolimnion (lower depths of the lake), which when oxidized can bind to and remove phosphorus from the upper levels.

The report's cautionary note involves blue-green algae or cyanobacteria (inset, left) which has been observed to release toxins as it dies off. These toxins can cause serious illness in humans and animals, and the Connecticut DEEP and Department of Health have established guidelines for shutting down public beaches when concentrations are high. Connecticut was the last of the New England states to address this issue. Remarkably, there are no local laboratories capable of doing the required tests. Shipping samples elsewhere can be time-consuming. Hopefully, these testing problems are temporary.

The good news is that Lake Waramaug's cyanobacteria levels have been consistently well below the danger threshold, due in large part to our long-term efforts to reduce phosphorus. But this recent focus on cyanobacteria toxins requires increased vigilance.

Consider Lakefront Buffer Planting

For many years The Lake Waramaug Task Force has been concerned that more nutrients are reaching the lake from shoreline lawns. Manicured lawns are gradually replacing the native plantings along the shore that helped protect lake water quality by slowing down storm run-off and absorbing nutrients, especially phosphorus and nitrogen. These nutrients feed and spur the excessive growth of algae and aquatic weeds.

In an effort to stem this trend and "turn back the clock", the Task Force conceived a plan to develop a model native shoreline buffer designed to protect water quality. The idea was to create an attractive shoreline of native plantings that would demonstrate how it protects the water and at the same time can be very attractive, provide low maintenance and low energy consumption compared to a suburban lawn.

The model shoreline buffer was installed at 47 West Shore Road, with the support of the property's owners and local environmental organizations. It is hoped that interested lake residents will visit the site and consider native plantings for their own shorelines.

This PDF lists the plants used on the site. Most are locally available. Please consider adopting this lakefront strategy for the long-term health of Lake Waramaug!

Summer 2013 Updates

Arrow Point Preserve Dedicated to Peter Mullen

On August 24, a perfect summer evening on Lake Waramaug's Arrow Point, ninety friends of the Mullen family, the Task Force and the Lake Waramaug Association gathered for a ceremony dedicating the LWTF's preserve at the end of the point to Peter P. Mullen.

The dedication plaque reads:
"This preserve is dedicated to Peter P. Mullen, in recognition of his 50 years of leadership and support in protecting Lake Waramaug, and to all who share his vision and commitment to preserve the health and beauty of this lake."

Tom McGowan, Executive Director of the Task Force, spoke of the many contributions made by Mr. Mullen, who passed away in October of 2011. Those initiatives, all of them critical to sustaining the lake's ecological health, are in evidence around the shoreline and in the watershed, and include the purchase of the Arrow Point property that now bears his name.

The preserve is the site of the Robert Frost aeration system, which plays a key role in the controlling of surface phosphorus and the reduction of algae growth.

The Mullen family with the Peter P. Mullen dedication plaque. Left to right: Jeff Mullen, Billie Mullen, Kirby Mullen, Lucy M. Ball, Elaine M. Peer and Peter C. Mullen.

Diatom Experiment Shows Encouraging Results

In the spring of 2012, the Task Force embraced a Diatom enhancement strategy for the lake at the suggestion of our limnologist Dr. Robert Kortmann.

Diatoms are a "good" form of algae that are prominent in cooler water in the spring. By activating our layer aeration systems earlier, we were able to expand those favorable conditions and hold off the transition to dominance of blue-green or "bad" algae. The trade-off yielded slightly poorer Secchi Disc readings of water clarity in April, followed by significantly better transparency from May through October (see chart).

The enhancement approach will be used again this spring and Dr. Kortmann is considering additional strategies to build on these encouraging results.

LWTF Summer 2013 Newsletter

Mark Twain was right when he said, "If you don't like the weather in New England now, just wait a few minutes." The temperature swings, the intensity of the rains and wind have all been "interesting'''!  But so far the water quality and clarity has held up despite these challenges.

Even with high levels of phosphorous being washed into the lake feeding algae and weed growth, our clarity has been amazing. We recorded 9.1 feet of visibility at our two mid lake test sites on August 5 - an excellent reading at any time but especially in August.

Read more here.