Mid Halton Wastewater Treatment Plant

Award of Excellenceat the 2020 Canadian Consulting Engineering Awards

438 mld
peak capacity UV disinfection

37 m diameter
anaerobic digester; chemical storage and feed facility

2 new
aeration tanks

Challenges

Conservation efforts have recently been made to clean Lake Ontario, the 14th largest lake in the world, as pollution has largely destroyed its commercial fishing industry.
Meet demand and continue protecting Lake Ontario's water by increasing the Mid Halton Wastewater Treatment Plant's capacity from 75 million liters per day (mld) to 125 mld.
Upgrade the plant’s headworks and install a new outfall tunnel, giving utmost consideration to crossing the environmentally sensitive 14 Mile Creek when planning the most direct route.
Protect the creek habitat for two owl species and Redside Dace fish, a government-designated endangered species requiring pools and slow-flowing streams with overhanging grasses and shrubs.

Provide primary design consultation services for the Mid Halton Wastewater Treatment Plant phase IV and V, including expansion and extensive upgrades to the headworks and outfall.
Design the headworks in 3D to give all stakeholders a clear view of the plan as it progressed.
Design a new outfall tunnel to run 1.3 miles onshore and another 2.7 miles offshore to an 85-to-98-foot underwater diffuser field in the final 300 feet.
Run the tunnel through bedrock, beneath a major highway and across the environmentally-sensitive area, drawing on our invaluable expertise in tunneling technology and computer modeling.

Final plan selection and outfall alignment required significant coordination with the Ontario Ministry of Natural Resources and the local conservation authority.
Ably demonstrated that our design and proposed construction methods would allow an alignment that crossed 14 Mile Creek while protecting the specialized habitat of the Redside Dace.
Ensured the area's needs are met for the foreseeable future, and Lake Ontario's water and the environment around the town of Oakville are protected.
Recipient of Award of Excellence in the Water Resources category at the 2020 Canadian Consulting Engineering (CCE) Awards.