Haydens Reservoir was created in 1929 by damming the Nissitissit River, a tributary of the Merrimack River. The reservoir covers an area of 114 acres and has a maximum depth of 25 feet. It is used for recreation, fishing, and irrigation by the surrounding communities. There are several public access points along the shore, as well as a boat ramp at the southern end of the lake. 

Haydens Reservoir is on Federal Hill Road.