CN Ste-Ann-de-Bellevue Tunnel

Project Overview

We were subcontracted by the KPH Turcot consortium to complete the CN tunnel demolition, a key component of Montreal’s $3.7 billion Turcot Interchange Reconstruction. Located beneath Boulevard Ste-Anne-de-Bellevue, the tunnel supported a vital CN rail corridor with four active tracks. As a result, the project demanded exceptional coordination and risk management to protect rail operations.

Structural Exposure and Assessment

To begin the CN tunnel demolition, our team excavated around the tunnel to expose it for structural analysis. The original 333-ft tunnel was a three-sided reinforced concrete culvert, 30 ft tall and 74 ft wide. Additionally, a 54-ft extension built with reinforced concrete box girders spanned the live tracks, requiring a separate dismantling plan.

Asbestos Abatement and Safety Measures

The tunnel’s ceiling contained asbestos fireproofing. Therefore, we conducted high-risk abatement using excavators equipped with scarifiers. This approach allowed us to safely remove the hazardous material before transitioning to mechanical demolition.

Dismantling the Tunnel Extension

We dismantled the extension in sections to reduce risk and improve control:

• Method: Saw-cutting and lifting of girders, slabs, and walls
• Weight: Up to 114,000 lbs per section
• Equipment: 500-ton mobile crane for heavy lifts

Dismantling the Original CN Tunnel

We removed the original culvert in nine sections, each weighing approximately 1,100 tons. To facilitate this, our team positioned a gantry crane over the structure. Meanwhile, SPMTs (self-propelled modular transporters) moved each section to a designated laydown area. In addition, we constructed a temporary rail-level crossing to enable safe crane access.

Final Demolition and Debris Removal

After completing hazardous material removal, we deployed large excavators to break down the remaining structures. Our crews then transported debris to certified recycling facilities, ensuring responsible material handling and minimal environmental impact.

Railway Coordination and Site Safety

Throughout the CN tunnel demolition, we maintained close coordination with CN to guarantee uninterrupted train movement. Moreover, strict safety protocols protected on-site personnel and surrounding infrastructure during all phases of work.

Project Outcome

We successfully completed the CN tunnel demolition on schedule and in full compliance with safety and environmental regulations. As a result, the site was safely cleared and made ready for future development, with minimal impact on live rail traffic.