Posted on October 11, 2022
With the first full dredging of Leyden Glen Reservoir since 1988 complete and coming in nearly $250,000 under budget, the city began the refilling process last week.
“Now that we’ve removed organics that accumulate over time and reduce water capacity and require more treatment, the reservoir should be good to go for another 20 to 25 years,” explained Department of Public Works Director Marlo Warner II.
Warner previously said that over time, the organic material that builds up at the bottom of the reservoir causes turbidity, or cloudiness.
“It’s nothing harmful, but we have to treat it, otherwise the water would be discolored,” he explained. “The more turbidity you have, the more costly it is for the water to enter and exit the (treatment) facilities.”
According to a city press release, crews closed the gate valve on Sept. 29, allowing the reservoir to refill to be brought back online as a water source. This marks the completion of the first full dredging of the city-owned reservoir in 34 years. A partial dredging was done in the late 1990s when repairs were made to the dam.
“We’ll let it get to half-capacity, do some water testing, and it’ll absolutely be there for us to use,” Warner said.
Precipitation patterns will determine how long it takes for the reservoir to refill, he said, but the process is expected to take at least two to three months.
Using sonar, Warner said it was estimated that about 50,000 cubic yards of sediment had accumulated in the reservoir. However, crews ultimately removed about 10,000 cubic yards of material, saving the city $247,850 off the expected $532,850 cost. The project was funded through the city’s Water Enterprise Fund and the work was done by Maverick Construction Management Services.
“We finished up approximately a month early … only because we didn’t have to remove the amount of material that was forecasted through the soundings,” he said.
Located in neighboring Leyden, the reservoir has a capacity of 44 million gallons and provides approximately one-third of Greenfield’s drinking water and fire-protection capacity. The Green River and Millbrook Wellfield provide the rest of the city’s water supply.
“We’re still in a major deficit with rain, even though we’ve received quite a bit,” Warner said, commenting on water conservation efforts in light of the statewide drought conditions.
Warner said although wells are looking better, the past few heavy rains “don’t necessarily recharge everything.”
Whether the city remains at its current drought status is up to the state’s Drought Management Task Force, he said.
“I thank taxpayers for their conservation,” he said. “It was very helpful.”