Stantec has been selected by the City of Toronto to provide design and construction administration services for a new High Rate Treatment Facility at the Ashbridges Bay Wastewater Treatment Plant.
The project is designed to reduce combined sewer overflows and improve water quality in the Lower Don River, Taylor-Massey Creek and Toronto’s Inner Harbour during wet-weather events.
The new facility will be located on the new landform at Ashbridges Bay and will form part of Toronto’s wider Don River and Central Waterfront Wet Weather Flow System.
600-million-litre-per-day treatment capacity
The High Rate Treatment Facility will provide primary treatment for excess flows captured during heavy rainfall and other wet-weather events. The planned facility will have capacity to treat up to 600 million litres per day.
The project builds on a wider network of tunnels and infrastructure designed to manage combined sewage and stormwater flows across Toronto. Once complete, the facility is expected to help reduce the volume of untreated combined sewer overflow entering local waterways.
“Toronto is making an important investment in protecting its waterways and preparing its infrastructure for the future,” said Jeff Berg, Vice President and Project Manager at Stantec.
“We’re pleased to work with the City to provide a solution that enhances water quality, safeguards public health, and strengthens climate change resilience.”
Part of Toronto’s wet-weather flow programme
The Don River and Central Waterfront Wet Weather Flow System is one of the largest wet-weather flow management programmes in Toronto’s history. It is intended to improve water quality by capturing, storing and treating combined sewer and stormwater flows before they reach rivers and the harbour.
The High Rate Treatment Facility is expected to be one of the final components of the programme, supporting environmental protection, public health and recreational use of local waterways.
Combined sewer overflows occur when sewers carrying both wastewater and stormwater become overwhelmed during heavy rainfall or snowmelt. In older urban systems, this can result in untreated or partially treated flows being discharged to nearby rivers, creeks or coastal waters.
Collaborative delivery model
Stantec will work with the City of Toronto and the construction team through a construction manager at risk delivery model. This approach brings the construction manager into the project earlier to support design input, constructability, scheduling and cost management.
The project is currently in the design and engineering phase, with construction scheduled to be completed in 2036.
Stantec has previously worked with the City of Toronto on several water and infrastructure projects, including phases of the Basement Flooding Protection Program and sections of the Gardiner Expressway Rehabilitation Project.
More information about Stantec’s work in wet weather flow and urban stormwater is available on the company’s website.
FAQs
What is Toronto’s new High Rate Treatment Facility?
It is a planned wet-weather treatment facility at Ashbridges Bay Wastewater Treatment Plant that will treat excess combined sewer and stormwater flows during wet-weather events.
How much water will the facility treat?
The facility is designed to treat up to 600 million litres per day.
Why is the facility being built?
It will help reduce combined sewer overflows and improve water quality in the Lower Don River, Taylor-Massey Creek and Toronto’s Inner Harbour.
What are combined sewer overflows?
Combined sewer overflows happen when older sewer systems carrying both wastewater and stormwater become overwhelmed during heavy rainfall or snowmelt, causing excess flows to discharge into waterways.
When will construction be completed?
Construction is currently scheduled to be completed in 2036.
