TURNERS FALLS — A recent oil spill at the Turners Falls Dam is believed to have been caused by a buildup of ice within one of the bascule gates.
The Massachusetts Department of Environmental Protection (MassDEP) issued FirstLight Hydro Generating Co. a Notice of Responsibility for the spill, which resulted in oil staining on the ice below Bascule Gate 4. According to FirstLight Communications Manager Claire Belanger, staff were not able to access the bascule gate and the pistons to inspect them for a cause due to the ice accumulation in the area at the time of the Feb. 25 oil release, but monitoring of the site continued until crews could gain access on March 2.
“While a definitive cause has not yet been established, current information suggests that the unusual weight of the ice buildup on the pistons, resulting from the extended stretch of cold weather, could have created a seepage pathway for oil to escape,” Belanger said in a statement. “Both the removal of the ice from the pistons and the injection of additional packing into the pistons were performed to address this issue.”
According to Belanger, ice buildup has happened at the bascule gates in previous years, but this year was worse based on low river flows coupled with the cold weather throughout January and February.
MassDEP’s Notice of Responsibility states that 36 gallons of hydraulic fluid had been added to the hydraulic system by FirstLight staff and, shortly after, the oil sheen was observed on the ice. Belanger clarified that it can’t be determined exactly how much fluid was released.
According to Belanger, FirstLight is involved in a multi-year effort to overhaul the current bascule gate system at the Turners Falls Dam by replacing the pistons within the gates. Already, Bascule Gate 1 was repaired in 2025, and no oil seepage has been present since.
“FirstLight continues to maintain close communication with the Massachusetts Department of Environmental Protection on matters related to the Turners Falls Dam and appreciates their support as we advance the shared goal of improved performance of the Turners Falls Dam,” Belanger’s statement concludes.
This is not the first time the Turners Falls Dam bascule gates have spilled oil into the Connecticut River, with the most recent being in June 2025. FirstLight was fined $25,062 in September for a 445-gallon oil spill from the dam that occurred on June 3, violating surface water discharge regulations and release notification regulations.
The administrative consent order from July 2025 explained that the violations were from pollutants being discharged without a permit from MassDEP and failure to notify MassDEP within two hours of “obtaining knowledge that a threat of release is present.”
FirstLight identified the leak to have originated from a piston located within Bascule Gate 2. FirstLight initiated an emergency drawdown of the Connecticut River above the dam to repair the gate on July 8.
MassDEP also issued a list of required next steps for FirstLight to take in the wake of the spill, including getting a professional engineer to assess the dam’s hydraulic system and alarm system within 60 days, and submitting a report within 180 days containing the engineer’s findings and plans to implement any of the engineer’s recommendations, along with a project timeline. At this time, Belanger confirmed that the engineer’s report was submitted in January, and FirstLight is following the recommendations of the report.