“This weekend RTG will resume work beneath Rideau Street between the Rideau Station cavern and east of Sussex Drive,” Cripps said. “This work is in preparation for the resumption of tunnelling which will begin early next week. Approximately 50m of excavation remains to complete the 2.5km tunnel.”
A majority of construction activities have resumed around Rideau Street, and watermain and utility repairs are completed in the Rideau and Sussex streets area.
The Rideau Station west entrance has been repaired, sidewalks are open to pedestrians and the roadway has re-opened to transit services and taxis. Work at the Rideau Station cavern, west entrance and east entrance is also underway.
The memo outlined measures in place to monitor progress and mitigate potential risk:
- The City of Ottawa, RTG and their tunneling experts will be on-site, both above ground and within the tunnel, monitoring activities.
- In accordance with the sequential excavation method (SEM), the tunnel will be mined in small pockets.
- Additional supports including pipe roofing, lattice girders and face bolts will be installed to reinforce the tunnel. Systematic drainage and grouting (injection of concrete to reinforce the area) will occur to mitigate any loose or potentially unstable ground.
- Monitoring of the ground and adjacent buildings will remain ongoing with increased monitoring of the newly installed watermains to detect any settlement or leaks.
Overall, the construction of the Confederation Line LRT project remains on schedule.
