Lake Housatonic, Derby - 2005

Lake Housatonic is a 328-acre body of water that is an impoundment of the Housatonic River. The maximum depth is 26 feet, and the mean depth is 10 feet. The lake is bounded by Route 34 and Osbornedale State Park on the eastern shore and by Indian Well State Park on the western shore. A boat launch owned by the state is located within Indian Well State Park. Between the cities of Shelton and Derby there is a 20 foot high hydroelectric dam. Due to the production of hydroelectricity the water levels may fluctuate. On the southern section of the lake there is heavy development within the cities of Derby and Shelton. On the northern end there is less residential development. Near the southwestern and middle section of the lake there are several retaining walls. 

The majority of the vegetation found in the lake during our July 2005 survey was observed near the shoreline in depths less than 6 feet. Pink House Cove, on the southeastern side of the lake in Derby, had large areas of horned pondweed (Zannichellia palustris), coontail (Ceratophyllum demersum), and eelgrass (Vallisneria americana).

The invasive minor naiad (Najas minor) was found in small areas along the western shore of the lake. Eurasian watermilfoil (Myriophyllum spicatum) was observed equally on both the eastern and western sides of the lake with a large occurrence in Pink House Cove. Curlyleaf pondweed (Potamogeton crispus) was found in small patches near Pink House Cove and also in small amounts along the western shore.