Mattawa Dundas Sanitary Trunk Sewer – Mississauga, Ontario, Canada

We provided design and engineering services during construction to the Regional Municipality of Peel for the Mattawa Dundas Sanitary Trunk Sewer Project in Mississauga, Ontario, Canada.

The project supports Peel Region’s long-term water and wastewater infrastructure needs. Through its Water and Wastewater Master Plan, Peel Region identified the need to upgrade existing sanitary trunk sewers and water mains in southeast Mississauga to support forecasted servicing demands through 2031.

Expanding Capacity And Reliability

To address these needs, the project included approximately 650 meters of new 1,200-millimeter-diameter sanitary trunk sewer near Dundas Street East and Mattawa Avenue. The new trunk sewer improves capacity at key locations within the existing sanitary sewer network.

Additionally, the project strengthens operational redundancy and system security across Peel Region’s sanitary trunk sewer network. These improvements help support continued growth while improving the resilience of critical wastewater infrastructure.

Minimizing Community And Environmental Impacts

The design and construction strategy focused on reducing impacts to the public, surrounding properties, and the environment. The project approach minimized disruption within regulatory boundary limits and reduced the need for property acquisition.

This strategy helped Peel Region deliver needed infrastructure upgrades while limiting effects on the surrounding community.

Supporting Complex Tunneling Construction

Tunneling construction was substantially performed by Ward & Burke Construction. The 1,200-millimeter-diameter tunnel boring machine advanced at an average production rate of approximately 10 meters per day.

Although the contract allowed for 24-hour tunneling operations, the contractor completed tunneling in 12-hour daily shifts. The alignment encountered mixed-face shale limestone conditions, including overburden soils, boulders, and shale limestone bedrock.

Despite these complex ground conditions, tunneling operations advanced successfully. The tunnel boring machine processed the encountered materials without significant issues.

Delivering Long-Term Wastewater Infrastructure

The Mattawa Dundas Sanitary Trunk Sewer Project was substantially completed in August 2025. With these upgrades in place, Peel Region is better positioned to meet future wastewater servicing needs, improve system reliability, and support continued growth in Mississauga through 2031 and beyond.