Cedar Swamp ACEC

Designation Date: July 1975

Cedar Swamp ACEC Designation Document

Approximate Acreage: 1650 acres
Municipalities: Hopkinton and Westborough
Watershed(s): Concord


Cedar Swamp was the first Area of Critical Environmental Concern designated in Massachusetts. The approximately 1650 acres are primarily vegetated wetlands, providing critical flood water storage capacity for the Sudbury River basin. The area is the headwaters of the Sudbury River and overlays the medium- and high-yield aquifers that supply two public wells for Westborough.

Cedar Swamp provides a large and important wildlife habitat in an increasingly urbanized area. State-listed rare species occur in the area, as well as the uncommon Atlantic White Cedar swamp for which the area is named. Located between the urban centers of Framingham and Worcester, the Cedar Swamp is also an important public recreation resource. Sudbury Valley Trustees and the DCR own lands that are used for hiking, canoeing, and nature study. Farther downstream, past the DCR reservoirs, the Sudbury River forms the core of the Great Meadows National Wildlife Refuge.

Since the designation was made in 1975, extensive archaeological studies have been conducted in the area. Much of the ACEC is now listed as an historic district on the State Register of Historic Places.

Water Bodies included (partially or entirely) in the ACEC

  • Rivers: Sudbury River
  • Lakes, Ponds: Cedar Swamp Pond (Westborough)
  • Brooks, Creeks: Denny, Jackstraw, Rutters Brooks (Westborough), Picadilly, Whitehall Brooks (Hopkinton, Westborough)


Cedar Swamp ACEC - Index Map

Cedar Swamp ACEC Map 3a

Cedar Swamp ACEC Map 3b

Maps are intended to be used with the written boundary description contained in the ACEC designation document. The mapped boundary is not to be used by itself for definitive ACEC boundary delineation or regulatory interpretation. For review of site-specific projects in or bordering the ACEC, determinations must be made in the field by a certified professional in consultation with the appropriate Conservation Commission(s) and ACEC Program Staff.


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