Your Watershed

The Neponset River Watershed includes roughly 130 square miles of land southwest of Boston. All of this land drains into the Neponset River, and ultimately into Boston Harbor.

Neponset Society Estuary Cruise August 15 2013

What is a Watershed?

  • A watershed is the area of land that drains into a body of water, like a river, pond, harbor or lake.
  • A watershed is sometimes referred to as a “river basin,” a “river valley,” or a “drainage basin.”
  • A watershed might contain a variety of landscapes, ecosystems, and man-made structures.  They come in all sizes and may contain multiple towns, just a few houses, or none at all!
watershed diagram

Click on image to see an example of a watershed.



A watershed could include forests – parking lots – mountains – wetlands – hills – streams – apartment complexes – ponds – cities – lakes – businesses – towns – landfills – state parks.




 Where is the Neponset River Watershed?

  • The River starts in Foxborough, near Gillette Stadium, and ends in Dorchester/Quincy, near the “Rainbow Swash” gas tank by I-93.
  • The Neponset River runs for 30 miles through the middle of the watershed.
  • Roughly 300,000 people live in the watershed.
Neponset River Watershed

Click on image for larger view.

Because the Neponset River ultimately flows into Boston Harbor, the Watershed is itself a part of the larger Boston Harbor Watershed, along with the Mystic River Watershed to the north of Boston, the Charles River Watershed to the west of Boston and the Weymouth-Weir River Watershed, which, like the Neponset River Watershed, originates south of Boston.

The Watershed includes parts of 14 cities and towns:

  • Hyde Park
  • Mattapan,
  • Dorchester
  • Canton
  • Dedham
  • Dover
  • Foxborough
  • Medfield
  • Milton
  • Norwood
  • Randolph
  • Quincy
  • Sharon
  • Stoughton
  • Walpole
  • Westwood
Walter Baker Dam, at Lower Mills, on the Neponset River presents an obstacle to fish migration.

The Walter Baker Dam on the Neponset River, at Lower Mills.

Watershed Issues

Watersheds are “communities connected by water.”  Everybody in each community is affected by the water use and water quality of their neighbors.

Currently, the Neponset Watershed suffers from:

  • contaminants in both river-bottom sediments and the fish that come into contact with them
  • very low water levels during the summer
  • obsolete dams that obstruct fish migrations
  • high levels of salt from winter road maintenance
  • filled wetlands
  • exotic, invasive species
  • garbage

What the Neponset River Watershed Association is doing to address these problems:

  • strengthening policy to protect the natural resources of the watershed,
  • commenting on development proposals to permit better water recharge for our river and underground water supplies,
  • boosting towns’ water-efficiency through school programs
  • offering rebates for water-efficient appliances,
  • managing a water-quality monitoring program (CWMN),
  • planning for the construction of stormwater treatment structures,
  • guiding abutters’ yard maintenance around a pond,
  • releasing biocontrol insects into wetlands to control exotic, invasive plants.

We could use your help!

Help us to protect the water, wildlife and land in your community! Become a member of the Neponset River Watershed Association, become a volunteer, or make a donation today!