Waterlevel & Dam

The waterlevel of Manchaug Pond is of utmost importance to the health of this lake ecosystem, the quality of life for year-round and seasonal residents and tourists, the safety of property and residences along the shoreline and downstream, and the maintenance of water in-lake and downstream flow feeding dependent fisheries, drinking water sources, water-dependent businesses. Key to maintaining the proper waterlevel is the Manchaug Pond Dam which is now owned, operated, and maintained by the Town of Sutton.

What’s happening at the pond!

Manchaug Pond FoundationSave




~ Mid-November: Communication with dam owner continues, meeting as recently as November 14th.  Shared goal remains to lower waterlevel ASAP and resume drawdown.

~ November:  Above average rainfall and runoff from a saturated watershed has brought the waterlevel up to summer levels.  The dam owner, who manages both Manchaug and Stevens Ponds, is working to bring both waterlevels down  so the winter drawdown can resume. Flow from Manchaug is being increased as Stevens Dam and downstream concerns allows. Manchaug Pond Foundation is in communication expressing concern and has requested gate 100% open and  flashboards out.

~ Winter drawdown began October 9th.  Make arrangements and adjustments for your boats and docks as the waterlevel goes down.  This year we are well over the full mark going into the drawdown.

~ October 6: Water continues to flow over the flashboards. Flow may be obstructed by debris at low-level gate.

~ October 2:  The increased flow out the low-level gate is to bring the level down with the additional rain and runoff.  Drawdown will begin as planned after the Columbus Day weekend.

~ August-September: Periodic rain brought us to “full.”  With good control of the dam, full continues to be maintained with water going over the flashboards at both Manchaug and Stevens Pond dams.

~ July 11: Hot dry weather with little significant rainfall continues to cause evaporation and a lowering of the waterlevel of Massachusetts lakes and ponds. The dam operator reports normal operations of both the Manchaug and Stevens dams with minimal outflows by design for a healthy Mumford River system.

~ July 1: Heavy rains have brought the waterlevel up closer to full in spite of the week’s temperatures in the 90’s.

~ June 26th: Low-level gate is closed. By design it does allow a minimal continuous flow for the health of the downstream habitat as required by the Department of Environmental Protection (MassDEP).

~ June 18th:  Down 4.5″ due to evaporation, high temperatures and lack of rainfall. Remember, by design, there is always a slight flow out the low-level gate even when closed as required by the Department of Environmental Protection (Mass DEP) for the health of the downstream river system.

~ April 30:  As of this morning we are 1″ over full!  The dam caretaker will continue to monitor regulating the flow as needed with the spring’s periodic rainfall.

~ April 1: Refill occurred in March as required by the Massachusetts Department of Environmental Protection.

~ March:   The beginning of the month saw no ice, the dam’s low level gate closed and the spillway flashboards ready for refill to accommodate the drier summer season.

March snowstorms have brought new snow cover to the watershed resulting in considerable snow melt and runoff bringing the lake up quickly.  Boats left on the shore are floating, and docks are in water.

~ March 1st: Conversation with the Town Administrator secured commitment for a deeper drawdown in the 2018-2019 winter season.

~ Freezing temperatures for an extended period freezing the lake and surrounding soils with little to no snow cover along the shoreline should result in freezing and desiccation of invasives to give better control next season.


Winter Lake Drawdown: Adjustments/arrangements should be made for docks and boats along the shoreline as the drawdown process begins. Public access through the state boat ramp is not impacted by the drawdown. Over the season, the Manchaug Pond Foundation has had several conversations with the dam caretaker with a drawdown goal of a deeper control of aquatic invasives.

~ October 15th: Caretaker reports continued drawdown looking to reach a lower 5.5 to 6 feet level, deeper than the past three years, as requested by the Manchaug Pond Foundation for more significant invasive weed/species control.

~ October 10th:  Drawdown continues with the lowest level historically realized in early January.  With recent rainfall, the reservoir level realized an gain. Low-level gate remains open.

~ October 30th: Recent heavy rains and continued runoff from the watershed have brought the waterlevel back up.  Dam low-level gate remains open. Residents should check docks and boats.

~ October 10th: Low-level gate opened just a few inches to slowly start the draw-down process letting out of Stevens Pond as well. Dam caretaker relates a record-able drop will show in about a week, with the water-level dropping an inch or two per day after that. By early January the lake will reach an anticipated low of between 4.5 and 6 feet.
~ October 3rd: At 10 inches below full due by enlarge to a lack of rain and evaporation. Last year were were 13 inches below and the year before 8 inches below.
~ September 18th: Lack of rain and evaporation has brought down the waterlevel a few inches. Tropical storm Jose is expected to bring an inch or so of rain to the area Tuesday-Thursday.
~ August 21st: This morning’s reading has Manchaug Pond just below FULL by 1 and 1/2 inches. Thank you Town of Sutton for maintaining a great level all season!
~ August 13th: With rain in the forecast, the dam low-level gate was opened a bit as we have been averaging about 3 inches over full. Steven’s Pond is also a consideration.
~ June 11th:Manchaug Pond remains at FULL+ with low-level gate closed to reduce flow today in effort to conserved water as hot weather arrives. Thundershowers in the forecast for Tuesday.
~ May 15th:Weekend rainfall and watershed runoff has put Manchaug Pond and Stevens Pond over the “full” mark. Manchaug Pond serves as a reservoir capturing rain and run-off to prevent flooding downstream and for use through the drier months. Today the dam low-level gate was opened more and high water is flowing nicely over the flashboards through the spillway. The dam caretaker is monitoring the level closely for both ponds.

Manchaug Pond Foundation

April 18, 2017, Public Boat Ramp




~ May: Lake is at full+, ready for the season with shoreline, coves and wetlands renewed.
~ April 5th:  Waterlevel is  quickly rising with continued rainfall, snowmelt and runoff from the watershed.  The channel wall is now submerged.  Docks are in water ready for boats!
~  March 26th:  Remainder of the ice is gone, fully opening the public access boat ramp to boaters.
~  March 15th:  Low-level gate is open in order to prevent dock damage as cold temperatures cause ice to form along the shoreline. The significant snow cover in the watershed from this week’s storm is good for the lake as the spring snow melt will be captured to increase the waterlevel of the reservoir for the drier summer season.
~March 14th: End drawdown to begin filling the reservoir. Waterlevel is about 10 days ahead of last year at this point.
~ March 1st:  Flashboards in, ice out, ready for refill.

















Frequently Asked Questions:

  • What are  the waterlevel goals?
    •  Late January-early February: End winter drawdown.
    • April 1st:  Achieve FULL. Refill of the lake from the winter drawdown occurs in February and March in order to bring the waterlevel to full or just above as required by Mass DEP (Massachusetts Department of Environmental Protection) and Mass Wildlife (Mass. Department of Fish and Wildlife) for healthy fisheries during spawning months.
    • Spring/summer: Maintain FULL as much as possible for connectivity to coldwater fishery stream and healthy fisheries in coves, wetlands and along shore as required by Mass Wildlife. This is dependent on rainfall and evaporation.
    • October/Columbus Day weekend: Winter DRAWDOWN begins.
  • Who owns the Manchaug Pond Dam?   The Town of Sutton owns the dam while the Manchaug Pond Foundation holds the deed to the flow-rights of Douglas and Sutton.
  • Who maintains the dam?  The dam owner maintains as needed.
  • Will another flashboard be added to the dam spillway?  No, the current number of flashboards are for normal operation and to get us to “full.”
  • Who decides if the gate is open or closed?  The dam caretaker makes that determination with input from the Manchaug Pond Foundation.Many variables are considered from the weather forecast, to the presence/absence of snow cover in the watershed and ice cover on the lake, to runoff and saturated soils or lack of in the surrounding watershed. Whatever the situation, you have a voice as the Manchaug Pond Foundation who works closely with the town. Waterlevel issues affect public safety, the health of the lake ecosystem, needs of shoreline properties, public access and recreation, flood prevention, drinking water wells and septic systems, control of invasive aquatic species, and more.
  • Why is the dam low-level gate open … or closed?  Possible reasons include winter lake-level drawdown, maintaining spring/summer season FULL, a rain or a storm event in the forecast, the low-level gate needs to be flushed, dam maintenance to be performed, or downstream work on the Steven’s Dam or a change in their water needs.
  • Is the dam safe?  The dam undergoes regular inspections both informal as part of its daily operation and formal as part of the requirements of the Massachusetts Office of Dam Safety.
  • Who can I contact with a question or concern?  Ask it here! We field  issues and concerns of the property owners and user-community serving as the liaison with local and state regulating agencies.
Drawdown allows for the desiccation, freezing and physical disruption of plants, roots, and seed beds around the shoreline.


Winter Lake-level Drawdown & Refill


Winter Drawdown:

October:  The annual drawdown of the waterlevel begins about Columbus Day. The water level will drop at a rate of approximately one inch to two per day, to achieve an approximate total level of 5.5-ft. below full with the process completed by-enlarge December 1st but reaching its lowest point in early January. This is a gradual drawdown with timing to allow for amphibians, reptiles and other aquatic organisms to move to deeper water before ice formation and substrate freezing and to provide fall recreational opportunities.

Lake Refill:

March-April: Lake refill must be achieved by April 1st to provide a stable pool elevation and habitat for spring spawning and connectivity with watershed in-flowing cold water fishery streams.*


Flood Control:

The lower winter waterlevel provides storage capacity for runoff from unusually high precipitation and snow-melt events.

Dam Maintenance:

With the upstream face of the dam exposed, inspection and maintenance can be performed as needed which would include re-pointing and facing of the concrete.

Invasive Species Control:

Since 1990, the Manchaug Pond Foundation and its parent organization, the Manchaug Pond Association, has worked with the dam owner to employ lake-level drawdown as the best option for controlling aquatic invasive species. Lycott Environmental’s Lee Lyman, a pioneer in the management of ecological systems, first recommended tweeking the timing of our annual drawdown to both protect native species and to control unwanted invasives.   Providing the weather conditions are conducive, historically the water level is drawn down during the middle of September and no later than mid October and at a rate of approximately one to two inches per day to minimize impacts to downstream environments and to allow certain aquatic organisms such as fresh-water mussels, crayfish, turtles and amphibians to migrate to deeper portions of the water body to overwinter and brought back in March and April.

Drawdown allows for the desiccation, freezing, and physical disruption of plants, roots, and seed beds around the shoreline. In addition to reducing the growth of non-native invasive weeds such as Fanwort and Variable Milfoil, Manchaug Pond Foundation notes successful control of Asian Clam at the state public access boat ramp.   A look at Manchaug Pond’s bathymetry  shows how lake-level drawdown can be an effective method for aiding in the management of aquatic vegetation in the shallow shoreline areas of lakes and ponds.Manchaug Pond Foundation



While the waters of Manchaug Pond Reservoir are no longer needed in the manufacturing processes of downstream textile mills, today the importance of the 380 acre reservoir and its dam are no less important and are found to be farther reaching:

  • provides required minimum, continual flow in the Mumford River supporting aquatic species;
  • supplies storage capacity to attenuate flooding concerns on-lake and downstream;
  • provides and enhances fisheries and wetlands;
  • ensures connectivity with in-flowing coldwater fishery streams;
  • allows year-round recreational opportunities benefiting tourism;
  • provides higher quality of life in this corner of the Blackstone Valley and Commonwealth.

Operation & Maintenance:

Visual inspections of the dam are made with daily water surface elevations and precipitation levels recorded and necessary adjustments made to the low-level gate and flashboards/stoplogs in compliance with the Conservation Commission and Mass DEP orders.

Annual maintenance includes cutting of the grass-covered earthen embankment twice a year. Re-pointing with concrete of the upstream stepped-face’s stone-masonry wall is done as needed. In compliance with Massachusetts Office of Dam Safety regulations, a Phase I Inspection/Evaluation is conducted every other year by an outside engineering firm.

In 2006 the low-level gate mechanism was replaced with steel construction and the operator’s platform renovated.

Repairs to the spillway box culvert were made in the years 2005, 2008, 2009, and 2013.

2015 new flashboards/stoplogs were installed.

Repairs to low-level gate in 2006
  • IMG_6874
  • IMG_6872
  • IMG_6894
  • IMG_6897
  • IMG_6899
  • IMG_0100
  • IMG_0101
  • IMG_0103
  • IMG_0107
  • IMG_0110
  • IMG_0111
  • IMG_0112
  • IMG_0113
  • IMG_0113
  • IMG_0114
  • IMG_0067
  • IMG_0070

Overall Structure & Construction

Manchaug Pond Foundation Waterlevel & Dam

2010 Aerial of Dam with Torrey Road at crest.

Originally constructed in 1836 by downstream textile mill owners, its primary purpose was to impound the pond creating a reservoir to provide the mills with a continuous flow through the year.  In 1960, extensive improvements were made which included widening and raising the dam crest, constructing the downstream earthen embankment, replacing the overflow spillway, expanding the low-level outlet, and accommodating Torrey Road.

Today, Manchaug Pond Dam stretches 330 feet long, 28 feet high, and 36 feet wide with Torrey Road at its crest and sits in the town of Sutton, Massachusetts, U.S.A. at Latitude 42.09048 N   Longitude 71.76630 W. The upstream side of the dam is a stepped-face stone-masonry wall made up of large stone blocks with joints mortared with concrete. The downstream slope is a grass/vegetation covered earth slope constructed in 1960’s.

  • Manchaug Pond Foundation Dam

    Dam viewed from Holt Road




  • IMG_6192

    Upstream side made of stone-masonry


  • Looking south toward low-level gate




  • Earthen downstream side




The overflow spillway was constructed in 1960 when extensive improvement were made to the dam.
Primarily a reinforced- concrete box culvert, it extends from the upstream side through the center of the day to the downstream side measuring approximately 10 feet. wide by 9.35 feet high.

2016: On February, 26th, new flashboards installed made of thick, red oak. Two flashboards were significantly damaged by a beaver in 2015.

  • Manchaug Pond Foundation Waterlevel & Dam

    Spillway with cage on upstream side

  • IMG_1193

    Spillway/culvert box opening with flashboards.

  • IMG_0085

    Culvert box of spillway as seen from upstream

  • dam flashboards

    Water flow over spillway flashboards

Low-level Gate

The low-level outlet is comprised of a hand-operated gate which opens to a 2 ft. by 2ft. stone conduit through the dam structure enlarging to a 2-ft. by 3-ft. high reinforced-concrete outlet on the downstream side of the earthen embankment, added during the 1960 construction.

Drawdown Performance Standards for the Protection of Fish and Wildlife Resources. Approved September 23, 2002, Massachusetts Division of Fisheries & Wildlife.