Chicopee treatment plant marks two years of sustained permit violations

At the confluence of the Chicopee and Connecticut Rivers, the Chicopee Water Pollution Control Facility has now spent two consecutive years out of compliance with its Clean Water Act permit. The most recent filing, dated August 8, still shows biochemical oxygen demand above its legal limit, a measure of how much organic waste is leaving the plant capable of consuming dissolved oxygen in the receiving water. That figure has run high in nearly every quarterly report since mid-2024, peaking at 187 percent over the permitted limit last December.

Aluminum discharges tell a similar story. Total aluminum has exceeded its limit repeatedly over the same period, including a September 2024 spike that ran more than 176,000 percent above the permit threshold, before settling into smaller, still-illegal overages that persisted through the most recent reporting period.

What makes this record notable isn't a single bad quarter caught and corrected; it's a facility that has remained in significant non-compliance status for two straight years, one of four currently flagged that way across the watershed. The timing of the oxygen demand overages compounds the risk: warm, slow-moving water in late summer already holds less dissolved oxygen, and loading additional organic waste on top of that raises the odds of oxygen-stressed conditions downstream in the Connecticut Valley. No fish kill or oxygen reading is attached to this record. Still, the pattern itself, sustained rather than incidental, is the finding here: a wastewater plant discharging above its legal limits into a major river system, quarter after quarter, without resolution.