Rehabilitation of the Louis-Hippolyte-La Fontaine tunnel

Maintaining traffic: adaptability and innovation at the service of users and clients.

The Louis-Hippolyte-La Fontaine (LHL) tunnel is a crucial axis linking Montreal to the South Shore, so our teams had to innovate to ensure work continuity while allowing users to travel. For example, it was agreed among the various teams to close one of the tunnel's tubes to facilitate the work while at the same time maintaining a traffic volume adapted to the new traffic capacity.

Work of this scale also requires a high degree of adaptability and agility in order to adapt the phasing to the progress of the project. Unlike more traditional construction sites, the rehabilitation of the LHL tunnel requires that mobility studies and design be carried out as the work progresses.

Due to the unforeseen events inherent in this type of project, our team must be very creative in resolving the various issues that may arise. It therefore adapts to the needs of the client and users to allow the progress of the project and continuous user movements, while ensuring safety for all.

Mitigation Measures and Monitoring: Traffic Flow and Safety

When detours are put in place or lanes are obstructed in a congested traffic environment, it is necessary to implement mitigation measures to minimize the risk of accidents and absorb high traffic volumes.

Our teams have implemented many mitigation measures, particularly on the R-132 and in the Anjou interchange. They ensure safe corridors using concrete barriers to prevent accidents caused by road incivility and promote traffic flow by preventing lane changes that cause slowdowns. A reserved route for buses and emergency vehicles has also been set up from the Radisson terminus to the tunnel.

To obtain data necessary for the next phases of work, traffic should be monitored daily. This makes it possible to know traffic flows, travel times, and traffic speed. This data is also communicated to clients, partners, and tunnel users.

Finally, our team reconfigured some traffic lights to ensure coherence among the various mitigation measures.