Staff Report / June 12, 2025
Officials confirm a chemical mishap at Ithaca’s Six Mile Creek water treatment plant during a routine delivery has been resolved, and the city’s drinking water remains safe.
On June 10, 2025, first responders were summoned to the City of Ithaca Water Treatment Plant, located along Six Mile Creek, after an accidental mixing of two treatment chemicals during a scheduled delivery led to the release of chlorine gas. Firefighters immediately evacuated the building, and a hazardous materials team was deployed to assess the situation. After post-incident monitoring, crews determined the plant was safe to reoccupy—but concerns lingered due to traces of residual chlorine gas detected the following day.
Fire officials returned early June 11, bringing in specialized hazmat units to ventilate the facility thoroughly. Once readings confirmed that chlorine levels had dropped to safe limits, plant staff were allowed back inside.
City officials emphasized that the incident posed no danger to the public. They noted that chlorine gas dissipates quickly in the open air, and critically, the city’s water distribution system—comprising approximately 85 miles of mains serving around 35,000 residents—was not compromised.
The plant, in operation since 1903, draws raw water from Six Mile Creek, then disinfects it using a multi-step process involving both chlorine and chlorine dioxide. This system meets or exceeds all U.S. EPA and New York State Department of Health standards
City spokespersons confirmed that water treatment and delivery continued without interruption, and that regular testing indicates no elevated chemical levels in tap water.
