Posted on August 3, 2026
The installation of the new outfall pipe for the Thornbury Wastewater Treatment Plant continues to move forward.
In a recent news release, the Town of The Blue Mountains provided an update on the project.
On the weekend of July 18 and 19, a portion of the turbidity curtain system used to limit the spread of suspended sediment generated by dredging was damaged beyond repair by sustained high winds and wave action on Georgian Bay.
“Over the past week, the town’s contractor has paused dredging operations and performed a thorough inspection of the recovered sections of curtain to determine how much of it could be effectively redeployed,” the news release stated.
The usable sections, along with additional curtains stored at Lora Bay Park that were to be used as dredging progressed into deeper water, will be redeployed in a modified configuration to support completion of the remaining dredging work.
The revised configuration will place usable curtain sections along both sides of the dredging corridor. The offshore end will remain open to reduce pressure from wind and waves, improving the system’s resilience during changing lake conditions. The contractor planned to begin reinstalling the turbidity curtain system and dredging possibly would resume on July 30, pending suitable weather and water conditions.
“Maintaining environmental and public health remains paramount in the amended plan. Continuous turbidity monitoring will remain in place during dredging. If the monitoring system detects turbidity levels in exceedance of approved thresholds, response actions will be implemented, up to and including temporary suspension of dredging,” the news release said. “The town has also engaged a third-party consultant to complete water quality testing periodically along the shoreline outside the dredging corridor.”
The news release explained that turbidity curtains are custom manufactured for each project based on measured water depths. Ordering new curtains to replace the damaged material is not feasible within the approved project budget. In addition, the time required to order, produce and receive new curtains could put the project at risk of exceeding the permitted timeframe for completing in-water work.
The town’s engineering consultant, the Ministry of Natural Resources, the Department of Fisheries and Oceans, and local conservation authorities have reviewed and approved the amended plan.
Once work resumes, dredging is expected to take approximately 15 working days to complete. The public will likely notice temporary visible turbidity or cloudiness in the water during the remaining dredging work. Turbidity curtains are not designed to be fully impermeable, however the majority of suspended sediment is expected to be contained within the curtained area.
Ongoing updates regarding the project will be posted to the town’s project webpage and emailed directly to project subscribers.
