The Sudbury Reservoir (2.02 square miles) is an emergency backup

Boston Boston (), officially the City of Boston, is the state capital and most populous city of the Commonwealth of Massachusetts, as well as the cultural and financial center of the New England region of the United States. It is the 24th- mo ...

metropolitan water reservoir in

Massachusetts Massachusetts (Massachusett language, Massachusett: ''Muhsachuweesut assachusett writing systems, məhswatʃəwiːsət'' English: , ), officially the Commonwealth of Massachusetts, is the most populous U.S. state, state in the New England ...

, located predominantly in Southborough and

Marlborough Marlborough may refer to: Places United Kingdom * Marlborough, Wiltshire, England ** Marlborough College, public school * Marlborough School, Woodstock in Oxfordshire, England * The Marlborough Science Academy in Hertfordshire, England Austral ...

, with small sections in

Westborough Westborough is a town in Worcester County, Massachusetts, United States. The population was 21,567 at the 2020 Census, in over 7,000 households. Incorporated in 1717, the town is governed under the New England open town meeting system, headed ...

and

Framingham Framingham () is a city in the Commonwealth of Massachusetts in the United States. Incorporated in 1700, it is located in Middlesex County and the MetroWest subregion of the Greater Boston metropolitan area. The city proper covers with a popul ...

. It was created when the Sudbury Dam was constructed to impound the Stony Brook branch of the

Sudbury River The Sudbury River is a tributary of the Concord River in Middlesex County, Massachusetts, in the United States.U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed October 3, 2011 Originati ...

; no part of the reservoir lies in the town of Sudbury. Nearly in the Sudbury Reservoir watershed are administered by the

Massachusetts Department of Conservation and Recreation The Department of Conservation and Recreation (DCR) is a state agency of the Commonwealth of Massachusetts, situated in the Executive Office of Energy and Environmental Affairs. It is best known for its parks and parkways. The DCR's mission is ...

as a limited-access public recreation area.

History

The reservoir was first begun in 1878, as part of a system of reservoirs fed from the

to supplement the

Lake Cochituate Lake Cochituate is a body of water in Natick, Wayland, and Framingham, Massachusetts, United States. Originally a reservoir serving Boston, it no longer serves that function, and is now a local recreational resource and home to Cochituate State P ...

system in

Natick Natick ( ) is a town in Middlesex County, Massachusetts, United States. It is near the center of the MetroWest region of Massachusetts, with a population of 37,006 at the 2020 census. west of Boston, Natick is part of the Greater Boston area. ...

. Today's reservoir was created by excavation from 1894 to 1898, with construction undertaken in sections. It was begun by the City of Boston but completed by the newly formed Metropolitan Water Board (predecessor to the modern

Massachusetts Water Resources Authority The Massachusetts Water Resources Authority (MWRA) is a public authority in the Commonwealth of Massachusetts that provides wholesale drinking water and sewage services to certain municipalities and industrial users in the state, primarily in th ...

). All told, construction required moving about of soil and boulders. Water began to fill the reservoir on February 8, 1897, with construction of the reservoir's new Sudbury Dam on the Stony Brook Branch of the Sudbury River completed later that year. When completed, the reservoir's surface area was , its average depth was and maximum depth was , and its capacity was . The reservoir was fed from the

Wachusett Reservoir The Wachusett Reservoir is the second largest body of water in the state of Massachusetts. It is located in central Massachusetts, northeast of Worcester. It is part of the water supply system for metropolitan Boston maintained by the Massachuset ...

on the west by the

Wachusett Aqueduct The Wachusett Aqueduct is a secondary aqueduct that carries water from the Wachusett Reservoir to the John J. Carroll Water Treatment Plant at Walnut Hill in Marlborough, Massachusetts. It is part of the public water supply system for the commu ...

(1898), and by local streams. To improve the water quality of the local streams,

filter beds Sand filters are used as a step in the water treatment process of water purification. There are three main types; rapid (gravity) sand filters, upward flow sand filters and slow sand filters. All three methods are used extensively in the water ...

were constructed adjacent to the reservoir. The reservoir's water was delivered to the

Weston Reservoir The Weston Reservoir is part of the greater Boston water supply maintained by the Massachusetts Water Resources Authority. It is located in central Weston, with its principal public access point on Ash Street. Until the 1960s, the Weston Reservo ...

to the east by the

Weston Aqueduct The Weston Aqueduct is an aqueduct operated by the Massachusetts Water Resources Authority (MWRA). Now part of the MWRA backup systems, it was designed to deliver water from the Sudbury Reservoir in Framingham to the Weston Reservoir in Weston. ...

(1901), or via a channel to the Framingham reservoirs and the

Sudbury Aqueduct The Sudbury Aqueduct is an aqueduct in Massachusetts. It runs for from Farm Pond at Waverly Street in Framingham to Chestnut Hill Reservoir in Boston’s Chestnut Hill neighborhood. A later built extension main runs from the Farm Pond gateh ...

to the

Chestnut Hill Reservoir Chestnut Hill Reservoir is a reservoir created in 1870 on existing marshes and meadowland to supplement the city of Boston's water needs, located in its namesake neighborhood of Chestnut Hill. A 1.56 mile jogging loop abuts the reservoir. Chestnu ...

. In 1947, the obsolete

Whitehall Whitehall is a road and area in the City of Westminster, Central London. The road forms the first part of the A roads in Zone 3 of the Great Britain numbering scheme, A3212 road from Trafalgar Square to Chelsea, London, Chelsea. It is the main ...

, Hopkinton, Ashland and Cochituate reservoirs became state parks; and in 1976, the entire Sudbury System was officially reclassified as an emergency water supply. Today only the Sudbury Reservoir and the Foss Reservoir (Framingham Reservoir No. 3) remain as reserve drinking water supplies with the Weston and Sudbury aqueducts serving as reserve transmission. In an emergency the Sudbury and Foss reservoirs can be placed into service either as a primary source, as an alternate pass-through for Quabbin/Wachusett reservoir water in the event of a transmission problem blocking the normal transmission pathways, or as a supplemental source in a major drought. In all cases, the water would be untreated and would likely require boiling for consumption.

Permitted activities

The area's limited public access allows for picnicking, hiking, snowshoeing, cross-country skiing, and shoreline fishing with restrictions.

References

Additional sources

* Science and Industry, Volume 6, The Colliery Engineer Company, Scranton, Penn: International Textbook Company, February–December 1901.

External links

Sudbury Reservoir
Department of Conservation and Recreation
MassWildlife Map and information
{{authority control Reservoirs in Massachusetts Framingham, Massachusetts Marlborough, Massachusetts Southborough, Massachusetts Westborough, Massachusetts Parks in Middlesex County, Massachusetts Parks in Worcester County, Massachusetts Lakes of Middlesex County, Massachusetts Lakes of Worcester County, Massachusetts 1898 establishments in Massachusetts Infrastructure completed in 1898