A project to renovate fireproofing inside the Leonard Tunnel at the Brussels Ring (R0) and E411 intersection near Tervuren starts on Monday night.
Work is expected to last three weeks and will take place at night to limit traffic disruptions on the heavily-used routes, according to local authorities.
Leonard Tunnel opened in 1976 and has weathered years of rain and vehicle exhaust fumes. In some places, specially equipped work crews will remove damaged fireproof plates containing asbestos.
The plan is to close only one lane at a time, alternating between the R0 (Waterloo-Zeventem tunnel) and the E411 (Brussels-Namur) tubes. Traffic will be diverted on surface routes.
Additional lane closures are scheduled for a few nights in May to replace lighting in each tube. A complete tunnel renovation is due to occur in autumn and last until 2023 and are expected to extend the tunnel’s life by at least another 25 years.