On 18 June, repairs to the tunnel's ventilation system will begin. The interventions will take place overnight, so there will be further night closures of the Grouft and Stafelter tunnels, between the Lorentzweiler and Waldhaff junctions.
The Roads and Bridges Administration did not specify how long the work is expected to take.
The ventilation issue was identified in January, leading to the ongoing closure of a lane in each direction and speed restrictions of 70 km/h.
Similar measures were implemented in the Stafelter tunnel but have since been lifted.
