Why is there a long queue to the Tunnel in periods of heavy traffic?
To allow vehicles to keep a distance between them of 150 m right from the Tunnel entrance, the toll barriers are timed to let a vehicle pass through about every 7 seconds. So it is not possible to increase the rate of traffic. When the flow is heavy, a queue will naturally form. The surveillance operators can reduce the flow of heavy vehicles by giving instructions to the regulation areas of Passy-Le Fayet and Aosta, but they cannot do anything about the flow of light traffic. The traffic information services are constantly informed about the waiting time. When an unplanned event takes place, for example a vehicle stopping inside the Tunnel, the movement of traffic is immediately suspended and the disturbance that arises from this can be of considerable duration.
