Mansfield Hollow Lake is a reservoir resting on the border of Windham County and Tolland County, Connecticut. It was created by the Mansfield Hollow Dam and is entirely contained within Mansfield Hollow State Park and the Mansfield Hollow Wildlife Area. Designed and constructed by the United States Army Corps of Engineers, this dam substantially reduces flooding along the Quinebaug, Shetucket, and Thames rivers. Construction of the project began in 1949 with completion in 1952 at a cost of US$6.5 million. The Mansfield Hollow reservoir is located within the Shetucket River Watershed and is part of the Thames River Basin. Access to the site is available from US Route 6 and State Route 195. The damsite, covering an area of, was listed on the National Register of Historic Places in 2003.DescriptionThe project consists of a rolled earth fill dam with stone slope protection 12420ft long and 68ft high. The spillway comprises a concrete weir 690ft in length. The weir's crest elevation is 16ft lower than the top of the dam. The permanent lake at Mansfield Hollow Dam, Naubesatuck Lake is 450acre in size. The flood storage area for the entire project covers about 1880acre in the towns of Mansfield, Windham, and Chaplin, Connecticut. The entire project, including all associated lands, covers 2472acre. The Mansfield Hollow Dam can store up to 16.1e9USgal of water for flood control purposes. This is equivalent to 5.8in of water runoff from its drainage area of 159sqmi.
