The Blackstone Watershed has over 300 dams, the most of any watershed in Massachusetts or Rhode Island.

Non-jurisdictional dams aren’t regulated they’re often not in the natl inventory of dams, don’t have fed ID#s each state assigns ID#s to dams but some non-jurisdictional dams/unregulated have no #s and are not required to have inspections for condition or assigned hazard levels. Some dams have an NID# but are no longer jurisdictional because they were breached.

Different IDs: NID is federal, state is dependent. MA uses federal, RI unique


(REPLACE WITH DAM MAP)

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1. Quinsigamond Pond Dam

NID: MA00139

Location: Worcester, MA (42.236216, -71.79687)

Owner: City of Worcester Conservation Commission (Local Government)

Hazard Level: High

Condition: Poor

Other information: The dam does not appear to currently serve any active operation or economic function, though it does impound water for limited passive recreational use.




2. Quinsigamond Pond Dam 2 aka Worcester Visitor Center Dam

ID: None (Non-jurisdictional)

Location: Worcester, MA (42.236972, -71.796083)

Owner: Unknown, potentially Mass DCR

Hazard Level: Unrated

Condition: Unrated; seemingly poor condition

Other information: This dam can easily be seen from DCR’s Blackstone Visitor Center balcony and may be part of DCR’s property.


3. Millbury Electric Dam

NID: MA02828

Location: Millbury, MA (42.190806, -71.747528)

Owner: National Grid (Private)

Hazard Level: Low

Condition: Partially breached

Other information: While this previously produced hydropower, it has not been active for decades and National Grid has pursued dam removal in the past (2007).


4. Pleasant Falls/Singing Dam

NID: MA02890

Location: Sutton, MA (42.180861, -71.730306)

Owner: Blackstone River Corporation, Trustee (Private)

Hazard Level: Significant

Condition: Satisfactory

Other information: Its nickname comes from the tonal vibrations produced as water passes over the spillway. This dam has an intentional, simple portage immediately upstream and downstream of the dam - one of the best on the whole river.

5. Wilkinsonville Dam

ID: None (Non-jurisdictional)

Location: Sutton, MA (42.177481, -71.720992)

Owner: Indusol Inc. Polyvinyl Films aka Stretch Tite (Private)

Hazard Level: Unrated

Condition: Partially breached

Other information: There is no known record of assessment or hazard classification for this dam. While this dam seems small, paddlers should use caution around it due to loose concrete and metal debris above and below the structure.


6. Saundersville Dam

NID: MA00578

Location: Grafton, MA (42.177778, -71.711944)

Owner: Officially “abandoned” per MA Office of Dam Safety, as the last known owner, Cacao Inc, dissolved

Hazard Level: Significant

Condition: Poor, partially breached

Other information: While many dams have unknown owners, this is one of only a handful of officially abandoned dams in Massachusetts, and the only one on the mainstem.

7. Fisherville Pond Dam

NID: MA00577

Location: Grafton, MA (42.179175, -71.688694)

Owner: Fisherville Redevelopment Company, LLC (Private)

Hazard Level: High

Condition: Poor

Other information: The Town of Grafton recently received funds to repair this dam, including modifying the dam height, which may include construction of a portage around the dam. Currently, the portage on river right is highly eroded and steep.


8. Farnumsville Dam

NID: MA00942

  • FERC: P-9100

Location: Grafton, MA (42.138883, -71.639781)

Owner: Riverdale Mills Corporation (Private)

Hazard Level: Low

Condition: Satisfactory

Hydropower: Active, 150kW authorized annually

Other information: This is an active hydropower dam and is the only dam on the river that generates direct power for the wire factory alongside it, instead of selling power to the grid.


10. Rice City Pond Dam

NID: MA00935

Location: Uxbridge, MA (42.097562, -71.622746)

Owner: MA Dept. of Conservation & Recreation (State)

Hazard Level: High

Condition: Fair

Other information: The dam impounds Rice City Pond and is part of Mass DCR’s River Bend Farm. This state park has hiking trails along the towpath, and access steps into both the river and canal.


11. Route 16 Dam

ID: None (Non-jurisdictional)

Location: Uxbridge, MA (42.079314, -71.619762)

Owner: Unknown

Hazard Level: Unrated

Condition: Breached

Other information: This small dam is only sometimes visible depending on water conditions, yet can still present a hazard to recreational paddlers. This dam is just south of Route 16 and the Stanley Woolen Mill, but is not part of the associated mill complex.


12. Blackstone Gorge Dam 

NID: MA00096

  • FERC: P-3023 (Eastern dam)

  • RI: 393

Location: Blackstone, MA (Western dam) / North Smithfield, RI (Eastern dam)

Owner: Blackstone Hydro Inc. (Private)

Hazard Level: Low

Condition: Satisfactory

Hydropower: Active, 1,724kW annual authorized capacity (Eastern dam)

Other information: This complex is actually two dams, one in MA and one in RI. The natural river turns south, but the canal/raceway turns north. The dam on the natural river is in Blackstone, MA (referred to as Stone Diversion Dam in MassMapper and also referred to as Rolling Dam). That dam creates a headpond that allows water to enter that raceway, which turns north, toward a hydroelectric facility called Tupperware. Water leaves Tupperware Dam/hydro facility and then releases water back into the natural river. These two dams are part of the same Tupperware project that produces hydropower.

The (western/natural river) Blackstone Gorge Dam on the mainstem is within a Mass DCR state park on the border of RI, with hiking trails along the Blackstone Gorge. Paddlers should be aware that the area south of here contains several rapids.


13. Saranac Dam

NID: MA01164

Location: Blackstone, MA (42.016999, -71.538106)

Owner: Town of Blackstone (Local Government)

Hazard Level: Low

Condition: Fair

Other information: Its official name is Blackstone River Saranac Dam at Canal Street.

16. Manville Dam

IDs: NID: RI00809

  • State: 059

  • FERC: 15370-000

Location: Cumberland/Lincoln, RI

Owner: Town of Cumberland (Local Government)

Hazard Level: Low

Condition: Poor

Other information: Hydroelectric estimated 3,952,000 kwh annually


17. Albion Dam

ID: RI00808/State ID: 060/FERC No.: P-14633

Location: Cumberland/Lincoln, RI

Owner: Albion Hydro, LLC (Private)

Hazard Level: Low

Condition: Poor

Other information: Hydroelectric, authorized capacity up to 520kW annually (technically exemption not licensed)


NID: MA00576

Location: Grafton, MA (42.174333, -71.680294)

Owner: Deborah Lippman Trustee (Private)

Hazard Level: Low

Condition: Poor, breached

Other information: The impoundment has mostly drained, leaving accumulated sediment exposed. This dam is composed of a wooden crib dam as well as a stone structure. Despite partial failure, water levels drop approximately 4 feet.


9. Riverdale Dam

18. Ashton Dam

ID:RI01705/State ID: 061/FERC No.: P-14634

Location: Cumberland/Lincoln, RI

Owner: Ashton Hydro, LLC (Private)

Hazard Level: Low

Condition: Poor

Other information: The dam is owned by New England Hydropower Company, who is proposing a run-of-river spillway hydropower facility. As of 2026, the project is not yet operational.


19. Pratt Dam

ID: RI01705/State ID: 062

Location: Cumberland/Lincoln, RI

Owner: Town of Cumberland (Local Government)

Hazard Level /Condition: Low/Poor (5/4/18)

Other information: This dam impounds water to form Lonsdale Marsh, the largest freshwater marsh in Rhode Island. Spillway arches are open to river flow so there is unimpeded connectivity for fish passage, but the narrow arches restrict flow during floods and create extremely hazardous conditions for paddlers - DO NOT try to paddle through this dam, despite the openings — debris accumulation is an ongoing safety concern that have led to fatal accidents.

20. Valley Falls Dam

ID: State: RI00401 NID: FERC: P-3063

Location: Cumberland/Central Falls, RI

Owner:Blackstone Hydro Associates (Private)

Hazard Level: Low

Condition: Satisfactory

Hydropower: Active

  • FERC: P-3063

  • Authorized capacity: 1,200kW annually

Other information: Impoundment includes the Valley Falls Pond and Valley Falls Marsh, which is the largest freshwater marsh in Rhode Island. This dam is the top of the “lowest four” that advocates are working to create fish passage around in order to reconnect migratory species such as herring from the ocean to this historic spawning habitat.

21. Elizabeth Webbing Mill Dam

ID: RI04270/State ID: 065

Location: Pawtucket, RI

Owner: State of RI Dept. Environmental Management

Hazard Level: Low

Condition: Poor

Other information: This dam is currently being explored by RIDEM and the Fish Passage Community Advisory Council to determine the best way to allow fish to go around or over the dam. Currently, the preferred alternative being explored is full removal and creation of a nature-like fishway within the river channel, which would allow both fish and paddlers to safely pass through.

22. Slater Mill Dam

ID: RI04270/State ID: 065

Location: Pawtucket, RI

Owner: Old Slater Mill Association (Private)

Hazard Level: Low

Condition: Poor

Other information: This dam powered the first successful cotton-spinning mill in the United States, kicking off the American Industrial Revolution. It is a central part of the Blackstone River Valley National Historical Park..

23. Main St. Dam

IDs: NID: RI04271

  • State:

  • FERC: P-3689

Location: Pawtucket, RI

  • (41.876556, -71.383136)

Owner: Relevate Power LLC

Hazard Level: Significant

Condition: Satisfactory Condition, Breached

Hydropower: Active

  • FERC: P-3689

  • Authorized capacity: 1,675kW annually

Other information: Active hydropower

15. Thundermist Dam

NID: RI03902

  • RI: 056

  • FERC: P-2972

Location: Woonsocket, RI (41°59’57.96, 71°31’4.76)

Owner: USACE - New England District (Federal)

Hazard Level: Low

Condition: Significant

Hydropower: Active, 1,200kW annual authorized capacity

Other information: This hydroelectric dam is allowed to produce up to 1,200kW per year and is a central component to the Woonsocket Flood Risk Management Program created by the US Army Corp of Engineers in _____Year