Pump Station Overflow Sends Wastewater to Harmony Creek in Oshawa

The Regional Municipality of Durham reported a wastewater overflow at Whitney and Tisdale Pump Station No. 3 in Oshawa on April 29, 2025. The pump station is located at 1125 Tisdale Street.

According to the Regional Municipality of Durham, the overflow began at 1:08 p.m. and ended at 2:32 p.m. The municipality identified a power disruption as the cause, which led to the malfunction of the pumps. Alarms notified staff, and personnel were sent to address the issue.

An estimated 560 cubic metres of untreated wastewater entered Harmony Creek, as reported by the Regional Municipality of Durham. The Ministry of the Environment, Conservation and Parks was notified, and signs were posted in areas near Harmony Creek to inform the public.

Crews from the Regional Municipality of Durham performed cleanup activities at the site, including inspection, debris removal, and water sampling. The municipality reported that the power issue was resolved and that the pump station returned to normal operation.

The Regional Municipality of Durham has advised residents to avoid contact with surface water near the overflow location for at least 48 hours following the incident.

All information in this article is based on the official incident summary provided by the Regional Municipality of Durham.