Two Ontario communities are moving forward with large-scale wastewater infrastructure upgrades designed to support rapid growth, enable new housing, and modernize treatment capacity. New construction is now underway in Carleton Place and set to begin soon in Brant County’s village of St. George, marking significant milestones for both municipalities.
The Town of Carleton Place, Ontario, has officially broken ground on construction of its largest ever infrastructure investment, a $133-million simultaneous expansion of both its water and wastewater treatment plants. Stantec, which has partnered with the town for years on long-term planning and detailed design, will provide construction-phase services, including contract administration and engineering support, to help deliver the multi-year project.
Both plants are being significantly upgraded to address operational constraints and accommodate the community’s rapid population growth, projected to rise from 15,000 to 25,000 residents over the next 20 years. The expanded systems will also help Carleton Place meet Ontario’s housing supply goals by enabling new development.
The wastewater treatment plant will see capacity rise from 7.9 to 10.6 million litres per day (MLD) on average, and from 22 to 42.5 MLD during peak hours. The expansion includes a conversion from conventional treatment to a membrane bioreactor (MBR) facility, strengthening reliability and effluent quality. The water treatment plant will increase its capacity from 12 to 19.5 MLD, with an expansion designed to fit seamlessly within its urban footprint while improving operator access.
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“We’re honored to support Carleton Place in this vital initiative,” said Pascal Pitre, project manager and managing leader for Stantec’s water group in Ottawa. “As a full-service firm, we bring the momentum and experience needed to manage complex infrastructure projects, helping communities like Carleton Place grow sustainably while protecting public health and the environment.”
ASCO Construction Ltd. has been awarded the construction contract following a competitive tendering process. Work is expected to continue into early 2029.
Brant County
In Brant County, Ontario, construction of a $56-million expansion of the St. George Wastewater Treatment Plant is expected to begin in January, supporting approximately 1,350 new homes approved for development over the coming decades. The project aligns with provincial priorities to increase housing supply and ensure infrastructure keeps pace with community growth.
Plant capacity will increase from 1,300 m³/day to 3,900 m³/day, guided by recommendations of the 2021 Class Environmental Assessment. The detailed design phase evaluated treatment technologies and selected MBR systems to meet stringent effluent requirements and fit the plant’s constrained site.
Design work was completed in July 2025, with a draft Environmental Compliance Approval issued by the Ministry of the Environment, Conservation and Parks. ROMAG Contracting Ltd., a Mississauga-based environmental contractor, will deliver the project after being selected through a prequalification and tender process.
Construction is expected to begin in January 2026 and conclude by March 2028. A phasing plan for development in St. George is being prepared as part of Brant County’s official plan and is expected to come before council later this year or in early 2026.
