Ontario Construction News staff writer
Construction has officially begun on all five future stations of the Montreal Metroโs Blue Line extension, the Sociรฉtรฉ de transport de Montrรฉal (STM) announced last week. The $1.1 billion construction contract has been awarded to the Mobilitรฉ Bleu Horizon consortium, composed of Pomerleau, EBC, and Spie batignolles.
Excavation is now underway at each of the new station sites, marking a major milestone in the long-awaited transit project. The consortium is also handling the construction of three auxiliary buildings that will support metro operations along the extended line.
Due to Montrealโs dense limestone bedrock, excavation work is particularly complex and generates significant noise, especially in the early phases when digging is closer to the surface. STM says noise mitigation measures are in place, including acoustic insulation walls, white noise backup alarms on trucks, and excavation methods that reduce reliance on jackhammers.
Rock extracted during construction is being transported to the nearby Saint Michel quarry. Its close proximity helps reduce greenhouse gas emissions from trucking and allows the material to be reused in future municipal infrastructure projects.
The Blue Line extension will add nearly eight kilometres of tunnel to the existing metro network, stretching from Saint-Michel to Anjou. It includes tail tracks and an underground train garage. Tunnel depths will range from 20 to 40 metres, depending on geological conditions and engineering considerations.
Stations are generally being constructed at shallower depths for easier passenger access. The track design includes slight uphill gradients as trains enter stations and downhill slopes as they leave, an energy-efficient configuration that eases braking and reduces power consumption.
Auxiliary buildings, located between stations at lower elevations, will house pumps and other systems to manage underground water accumulation.
The extension is a key part of Montrealโs broader effort to expand and modernize its public transit network, with completion targeted for 2031.