Record-Speed Excavation Advances as Limone-Riva Tunnel Near Completion

Work on the new tunnel connecting Limone to Riva is progressing at record speed.

Excavation activities and progress of the works

Twice a day, 110 sticks of dynamite are detonated on the four excavation fronts. Each blast shatters tons of rock, and the tunnel advances into the mountain by nearly thirty meters per day.

According to Raffaele De Col, a technician from the Provincia di Trento, the authority that has invested 75 billion lire in this project, “the works are proceeding smoothly,” and the raw tunnel could be completed by June 15.

Recent inspections also indicate that hydrogeological complications are unlikely during the excavation phase.

Progress and characteristics of the tunnel

On the Limone side, excavation has surpassed 150 meters in length, while on the opposite Riva side, it has exceeded 120 meters.

The main tunnel, once completed, will be 920 meters long.

Meanwhile, the central safety conduit has been constructed — a five-meter-wide duct running from the center of the tunnel to the coastal road.

This has allowed work to proceed on the central fronts, which were added to those opened on March 5 from Riva and Limone.

Methods of consolidation and reopening hypotheses

To consolidate the tunnel walls, a quick-setting concrete mixture called “spriz-beton” is sprayed onto the rock surface.

Regarding the partial reopening of the land route between Limone and Riva, the hypothesis of allowing traffic access for a few hours a day is gaining traction, once the initial phase of the tunnel construction is completed, around June 15.

In this scenario, traffic will be regulated in alternating directions with a special operative measure: the column of vehicles will be preceded by a security service vehicle, similar to the safety car in Formula One racing.