Before renovation work started, the tunnel, built in 1987, presented a certain degree of general degradation, from ceiling to road deck and including the entry and exit ramps.
The contract includes repairs to the structural work, reconstruction of the roadway and surrounds (sidewalks, gutters etc.), technical rooms and 17 emergency exits, as well as asphalting and the general waterproofing of the tunnel. More generally, the tunnel needs to meet current compliance requirements, for example in the area of fire safety.
Before starting work, asbestos had to be removed in an 18,000 m² containment zone.
The specific tunnel equipment also needed replacing, including 800 km of cables, ventilation, communication and surveillance equipment, lighting, etc.
Finally, the interior aesthetics have been totally redesigned.
Work began in May 2018 and will last for 39 months. The CIRCUL 2020 consortium will then maintain the tunnel for 25 years, including equipment replacement and various repairs.