WESTFIELD – The City Council voted last week to accept a $631,000 grant from the state’s Executive Office of Environmental Affairs to remove the Winchell Reservoir Dam in Granville which is no longer used as part of the city’s drinking water distribution.
The Winchell Dam was constructed on Hollister Brook in 1898 to collect water that was then piped into the city through a pipeline constructed on the north face of the Granville Gorge.
Charles Darling of the Water Resource Department said that the city needed more water than the Winchell Dam could provide and constructed the much larger Granville Reservoir Dam, which came on line in 1930 and is currently a chief source of municipal drinking water.
The Winchell Dam is much lower and is located near convergence of Hollister and Munn brooks at the upper throat of the Granville Gorge.
Darling said projected cost of the dam removal project, and environmental remediation associated with the dam removal, is $816,500 and that the city will contribute $180,500 through the in-kind use of Water Resource personnel and equipment.
“We’re preserving a part of the dam, the gatehouse and one abutment, as an example of a historic dam structure and plan to salvage the granite stone for other uses in the city,” Darling said. “As part of the dam removal we plan to remove silt that has collected behind the dam and restore the natural flow of the stream.
Darling said the dam is classified by the state as a “significant hazard dam” because of the damage which could occur downstream is the dam failed.
The volume of water retained in the reservoir behind Winchell Dam is much lower because silt has filled much of that reservoir over the past century reducing storage capacity.
The Office of Dam Safety maintains records of dams located throughout the Commonwealth, ensures compliance with acceptable practices pertaining to dam inspection, maintenance, operation and repair and removal of dams.
The Office of Dam Safety has three dam classifications:
High Hazard Potential dam refers to dams located where failure will likely cause loss of life and serious damage to home(s), industrial or commercial facilities, important public utilities, main highway(s) or railroad(s).
Significant Hazard Potential dam refers to dams located where failure may cause loss of life and damage home(s), industrial or commercial facilities, secondary highway(s) or railroad(s) or cause interruption of use or service of relatively important facilities.
Low Hazard Potential dam refers to dams located where failure may cause minimal property damage to others. Loss of life is not expected.
