The Goodnough Dike was named after Xanthus Henry Goodnough, who was an engineer for the State Board of Health through the early 1900s and was a key person in the creation of the Quabbin Reservoir. It was built at the same time and in the same way as the Winsor Dam, except for the outlet into the Swift River and the Spillway (both features of the dam). The difference between a dam and a dike is that a dam holds back a flowing body of water (river or stream) and releases water by a spillway or discharge pipe, whereas a dike is simply a wall holding water in. On the upper road of the dike is a short, easy trail showing different stages of forest management and habitats. It is a nice walk and a good, quiet place to observe wildlife.

Goodnough Dike is a massive earthen dam that separates the Quabbin Reservoir from the Swift River Valley in Massachusetts. The dike was built in the 1930s as part of the Quabbin Project, which created the largest inland body of water in Massachusetts and supplied drinking water to Boston and other cities. The dike is 2,640 feet long, 650 feet wide at the base, and 150 feet high. It has a road on top that offers scenic views of the reservoir and the surrounding hills. 

The Quabbin Reservoir is a remarkable engineering feat that provides water to millions of people in Massachusetts. It was constructed in the 1930s by damming the Swift River and flooding four towns in the process. The reservoir covers an area of 39 square miles and has a capacity of 412 billion gallons. The Quabbin Reservoir is a popular destination for fishing, hiking, and wildlife viewing. The reservoir is surrounded by a protected forest that hosts a variety of plants and animals, some of which are rare or endangered. 

Quabbin Reservoir is one of the largest unfiltered water supplies in the United States. Along with the Wachusett Reservoir and Ware River, it is the source of high-quality water for the Massachusetts Water Resources Authority water supply system. Recreational activities are regulated and limited to protect 3 million people’s drinking water.