Lake Winchester is a state-owned 246-acre lake located in Winchester, CT. It has little development in the surrounding forest. Boating is made difficult by the many tree stumps, many of which are just below the surface. There is a public boat launch and a dam at the southern end. On average the lake is 3 meters (9 feet deep) but it reaches depths of 17 feet.

Our September 2007 aquatic plant survey found twenty-one aquatic plant species, none of which were invasive. The dominant plant was purple bladderwort (Utricularia purpurea), which was found throughout the entire lake. Eelgrass (Vallisneria americana) occurred with almost as much frequency. Bur-reed (Sparganium species), small waterwort (Elatine minima), low watermilfoil (Myriophyllum humile), sevenangle pipewort (Eriocaulon aquaticum), and ribbon-leaf pondweed (Potamogeton epihydrus) were also common submersed species. White water lily (Nymphaea odorata), watershield (Brasenia schreberi), and yellow water lily (Nuphar variegata) were very common in the coves. Less common were the emergents rush (Juncus species) and pickerelweed (Pontederia cordata). Isolated patches of floating-leaf pondweed (Potamogeton natans), snailseed pondweed (Potamogeton bicupulatus), spotted pondweed (Potamogeton pulcher), large-leaf pondweed (Potamogeton amplifolius), and floating bladderwort (Utricularia radiata) were present. All other species listed below were found infrequently. As expected, the highest plant densities and diversity were found in the shallow coves.