Pittsfield to treat Onota Lake for zebra mussels in November
Pittsfield will apply the molluscicide EarthTec QZ at Onota Lake on Nov. 2, 9 and 16 to control a potential zebra mussel infestation near the Burbank Park boat ramp, with swimming banned for people and pets on those days.
The City of Pittsfield announced Oct. 27 that it will carry out a series of treatments at Onota Lake to control a potential infestation of invasive zebra mussels.
The applications of EarthTec QZ are scheduled for Monday, Nov. 2, Monday, Nov. 9 and Monday, Nov. 16, 2026, in a 1-acre zone around the public access boat ramp and fishing pier within Burbank Park.
The city said zebra mussels are a highly invasive species that can rapidly alter aquatic ecosystems and disrupt native wildlife, and it is taking proactive, preventative action to eradicate the potential threat before it establishes a permanent presence.
Swimming will be strictly prohibited for humans and pets on each of the three treatment days. The Onota Lake boat ramp will remain open for public use throughout.
EarthTec QZ is an EPA-registered molluscicide designed to target and control invasive mussels while minimizing risks to non-target aquatic life. The city said the treatment will be applied and monitored by licensed professionals in compliance with state and federal environmental standards.
The city asked for public cooperation with the temporary swimming restrictions to ensure a safe and effective application process.
Residents with questions can call Parks, Open Space and Natural Resource Program Manager Jim McGrath at (413) 499-9344.
Source: City of Pittsfield announcement, October 27, 2026.
Checked against the record: before publication this article was automatically compared with the original announcement.
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