Piora syncline definitively and successfully mastered

The geologically challenging Piora syncline has been mastered. On February 3, 2009, the tunnel boring machine in the west tunnel of the Gotthard Base Tunnel cut through the last meters of the Piora syncline and reached the Medels granite. The tunnel boring machine in the east tunnel already mastered the Piora last October.

As already in the east tunnel, no special problems were encountered in cutting the west tunnel. On January 20, 2009, the tunnel boring machine in the west tunnel cut into the first metres of the Piora syncline. Almost exactly two weeks later, on February 3, 2009, it reached the Medels granite that lies to the north of the Piora. Advancing at a rate of 10 to 12 m per day, the tunnel boring machine made good progress through the approximately 150-metres-long Piora syncline. The rock behaviour was stable. No notable deformations were detected in the dolomitic rock, and no water was encountered.
In the west tunnel, a further 7.3 km of rock remain to be cut before breakthrough takes place between Faido and Sedrun. In the east tunnel, the distance is 6.4 km. Provided that all progresses as planned, the main breakthrough of the Gotthard Base Tunnel will take place at the beginning of 2011. Commercial operation of the Gotthard Base Tunnel with scheduled train services is expected to start at the end of 2017.