Shawsheen watershed map
The Shawsheen River Watershed is located in northeastern Massachusetts. It has a total drainage area of approximately 78 square miles, including approximately 60 miles of named rivers and streams, and encompasses all or part of 12 Massachusetts municipalities.

Representing one of the smaller watersheds in the state, the mainstem of the Shawsheen River flows 25 miles from its headwaters at the Hanscom Air Force Base in Bedford, losing 70 feet in elevation as it travels to its confluence with the Merrimack River in Lawrence. The watershed has an urban character throughout and supports a population of approximately 250,000 people. Approximately 4.5% of the watershed area is covered by wetlands or open water.

The Shawsheen River represents the only major tributary to the Merrimack River that does not have a dam or any other man-made obstruction from its confluence to the Atlantic Ocean, making it an easy access for numerous species of anadromous fish. According to legend, the name "Shawsheen" is actually a Native American word, meaning "serpent" or "serpentine," which refers back to the meandering nature of the river.

Watershed Priorities

  • View of Shawsheen River
    Continue to monitor and work to improve the fluctuations of water flow, both high and low flows, throughout the basin
  • Work to improve water quality
  • Promote efficient growth management practices and emphasize the importance of open space preservation and habitat conservation
  • Build constituencies throughout the watershed
  • Increase recreational opportunities throughout the watershed by improving access to local waterways

Watershed Success

Over twenty stream teams were trained to conduct river walk surveys and water quality sampling at over 120 stations within the watershed. These stations cover over 90% of the basin area. Due to the results of these surveys and follow-up cleanups of pollution hot spots, it is likely that the Department of Environmental Protection will be able to remove the basin from the list of impaired waters in the near future.

Watershed Publications

Watershed Links

Shawsheen River Watershed Association




This information is provided by the Executive Office of Energy and Environmental Affairs, Office of Water Policy