Metrolinx and the government of Ontario have chosen the Sener engineering and technology group to develop the design to extend Line 2 of the Toronto subway further into Scarborough by performing the stations, track and systems contract for the project. 

The extension spans 7.8 km(4.8 miles) and is entirely underground. It will feature three new underground stations, each equipped with surface-level bus terminals to support seamless connections between transit modes. The project also includes the refurbishment of an existing station, the construction of eight emergency exit buildings, and the installation of four new electrical substations. Sener is tasked with delivering the detailed design across multiple disciplines, including architectural and structural components, electromechanical systems, geotechnical works and station caverns, ventilation, electrification, signaling and train control, communications, track design, landscaping, and utilities. Additionally, Sener will oversee systems integration and safety certification.

The new segment of the Toronto subway is projected to serve approximately 105,000 passengers each day, including an estimated 52,000 individuals who are new to the subway system. This increase in ridership is expected to cut greenhouse gas emissions by up to 10,000 metric tons annually. The project is being delivered through a Progressive Design-Build model—an integrated, collaborative approach designed to enhance coordination among the project owner, contractors, communities, and other stakeholders, while minimizing execution-phase risks. Sener has been involved since the early stages, working alongside Aecon and FCC Canada Limited. Their contributions began with supporting the consortium selected by Metrolinx and continued through the preliminary design phase, playing a key role in securing the contract.