Watertown Dam

The Watertown Dam spans the Charles River 980 feet (300 m) upstream from the Watertown Bridge near Watertown Square in Watertown, Massachusetts. 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. Ist length is 220 feet (67 m). Ist capacity is 30 acre feet (37,000 m³). Normal storage is 20 acre feet (25,000 m³). It drains an area of 0.2 square miles (0.52 km²).

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 Charles River. 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) 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, great black-backed gulls, great blue herons, night herons and cormorants.

Text imported from Wikipedia article "Watertown Dam" and modified on March 30, 2021 according to the CC-BY-SA 4.0 International license.