The Quebec Ministry of Transport, Sustainable Mobility and Transport Electrification (MTMDET) has just awarded the CIMA+/Egis consortium the missions of Expert Advisor and Independent Engineer (CEII) as part of the major refurbishment of the Louis-Hippolyte–Lafontaine Tunnel and related works, delivered within a design-build-finance contract.
The TLHL is a 1,400-metre immersed tube tunnel on the north-south Trans-Canada highway and runs from Montreal to Longueil, passing beneath the Saint Lawrence River. It remains to this day the longest immersed tube tunnel in Canada.
As a strategic infrastructure link for passenger and freight transportation (located immediately next to the Montreal port zone), it is used by 120,000 vehicles per day, running at maximum capacity almost 10 hours every day.
Having first opened to traffic in 1967, the TLHL is today in need of major renovation (civil engineering, safety and operating facilities, ventilation). The project also includes the reconstruction of concrete slabs on the A25 highway approaching the tunnel.
Egis, working with the Canadian design consultancy CIMA+, is supporting the Ministry in this complex assignment.
The TLHL is an urban structure with high density traffic. The first challenge of the project is to conduct work without interrupting traffic (including major resurfacing) in a confined space and to a tight schedule (a maximum of 4 years including no more than 2 years of traffic disruption), whilst guaranteeing the best possible safety and mobility conditions for light and heavy vehicles.
Another major factor to be taken into consideration is the region’s high rainfall and low winter temperatures, so as to guarantee not only the timely progress of the refurbishment work but also the long-term durability of the infrastructure.
Alongside its partner CIMA+, one of the largest consulting engineering firms in Canada, Egis has a dual role. As Expert Advisor, Egis will review costs, timeframes, risks and their ideal allocation, and optimise the project’s technical requirements. As Independent Engineer, Egis is tasked with overseeing compliance with technical requirements, drawing up a quality assurance plan and certifying compliance of the delivered works.
To successfully fulfil this project, Egis will draw on its specialist technical skills in the fields of tunnels and underground works, and on its long-standing experience in tunnel renovation conducted without closures. As the TLHL is a complex industrial installation which relies on a wide range of systems and subsystems – which must always remain operational – our teams are also responsible for recommending innovative solutions with regard to construction methods and the organisation of the project under routine operating conditions.