The Watertown Dam spans the

Charles River The Charles River ( Massachusett: ''Quinobequin)'' (sometimes called the River Charles or simply the Charles) is an river in eastern Massachusetts. It flows northeast from Hopkinton to Boston along a highly meandering route, that doubles bac ...

upstream from the Watertown Bridge near

Watertown Square Watertown Square is the main square of Watertown, Massachusetts, located at the confluence of North Beacon Street and Main Street ( US-20), Mt. Auburn Street ( MA-16), Pleasant Street, Arsenal Street, and Charles River Road. The Armenian Library a ...

in Watertown,

Massachusetts Massachusetts (Massachusett: ''Muhsachuweesut Massachusett_writing_systems.html" ;"title="nowiki/> məhswatʃəwiːsət.html" ;"title="Massachusett writing systems">məhswatʃəwiːsət">Massachusett writing systems">məhswatʃəwiːsət'' En ...

. The dam is located where the Charles River tidal estuary historically ended (the tides no longer reach this point because of the downstream Charles River Dam). Watertown Dam is of Concrete construction, a gravity dam. Its length is . Its capacity is . Normal storage is . It drains an area of . The history of the dam traces back to 1632 when construction of a fish weir was authorized. The current dam, maintained by the Department of Conservation and Recreation, dates from 1900. It is part of the Upper Charles River Reservation.

Ecological impact

The Watertown Dam is the second of numerous dams located along the length of the

. The current earthen dam creates an obstacle for the river herring that run in the spring, but herring have long been harvested at this site. The Pequossette (one of the tribes of the

Massachusett people The Massachusett were a Native American tribe from the region in and around present-day Greater Boston in the Commonwealth of Massachusetts. The name comes from the Massachusett language term for "At the Great Hill," referring to the Blue Hill ...

) inserted stakes into the river then interwove brushwood to create a weir that would trap the herring as the tide went out. Today, a fish ladder provides access to upstream spawning habitat as part of a system of fish passages that provide access up to river mile 20. The high concentrations of blueback herring and alewife below the dam in the spring make it a popular fishing spot for

herring gulls Herring gull is a common name for several birds in the genus ''Larus'', all formerly treated as a single species. Three species are still combined in some taxonomies: * American herring gull (''Larus smithsonianus'') - North America * European he ...

, great black-backed gulls,

great blue heron The great blue heron (''Ardea herodias'') is a large wading bird in the heron family Ardeidae, common near the shores of open water and in wetlands over most of North America and Central America, as well as the Caribbean and the Galápagos I ...

s, night herons and

cormorant Phalacrocoracidae is a family of approximately 40 species of aquatic birds commonly known as cormorants and shags. Several different classifications of the family have been proposed, but in 2021 the IOC adopted a consensus taxonomy of seven ge ...

s. File:Great Blue Heron readying to strike.JPG, Readying to strike File:Great Blue Heron catching Herring.JPG, Heron has fish under water File:Great Blue Heron spears Herring.JPG, Successfully speared File:Great Blue Heron with Herring.JPG, With herring

References

{{Crossings navbox , structure = Crossings , place =

, bridge = Watertown Dam , bridge signs = , upstream =

Thompson Footbridge Thompson may refer to: People * Thompson (surname) * Thompson M. Scoon (1888–1953), New York politician Places Australia * Thompson Beach, South Australia, a locality Bulgaria * Thompson, Bulgaria, a village in Sofia Province Canada ...

, upstream signs = , downstream = Watertown Bridge , downstream signs = MA Route 16

Dams in Massachusetts Buildings and structures in Watertown, Massachusetts Charles River Dams completed in 1900 1900 establishments in Massachusetts Crossings of the Charles River