| Squannacook River | |
|---|---|
Squannacook RiverTownsend Harbor | |
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| Type | Scenic |
| Designated | March 12, 2019 |

TheSquannacook River is a 16.4-mile-long (26.4 km)[1] river in northernMassachusetts. It is a tributary of theNashua River and part of theMerrimack River watershed flowing to the Atlantic Ocean.
The river rises withinWest Townsend,Massachusetts, at the juncture of Walker Brook, Locke Brook, and Willard Brook. Walker and Locke Brooks rise withinGreenville,New Ipswich, andMason, New Hampshire, while Willard Brook rises inAshby, Massachusetts. The Squannacook flows east and southeast through Townsend andWest Groton, Massachusetts, and joins the Nashua River in wetlands just east of Woodsville. The river is dammed three times in Townsend and twice in West Groton. Its watershed covers 73 square miles (190 km2), of which 18% is permanently protected. It has been designated an Outstanding Resource Water.
There has been a conversion of one of the former mills on the Groton portion of the river. Theformer E.H. Sampson Leather Board Mill became a senior citizen/ nursing home. Riverside is located next to West Groton Square.
42°34′52″N71°36′32″W / 42.581°N 71.609°W /42.581; -71.609