The Goodnough Dike (actually a dam) is on the southeastern end of the Quabbin Reservoir, the largest water body in Massachusetts.

The Goodnough Dike is not as large as the Winsor Dam, but it is equally important as they both trap the waters of the Quabbin Reservoir.

The dam was named after X. Henry Goodnough, who was chair of the Boston Metropolitan Water and Sewer Board during 1921.

Frank E. Winsor was chief engineer of the Board from 1926 until his death in 1939 and as such was deeply involved in the design construction of Goodnough Dike as well as Winsor Dam and Quabbin Reservoir The Quabbin Reservoir is one of the largest fabricated public water supplies in the United States.

Construction of the reservoir remains a great engineering feat and Quabbin is one of the largest unfiltered water supplies in the world.