After a year of preparatory works, the IBD consortium of Implenia, Bernasconi and De Luca began blasting on the 2.1km-long twin-track tunnel last week. The first 250m of the tunnel have been excavated mechanically using an excavator and excavation hammer and blasting will be used on the remainder of the tunnel.
The almost one million tons of excavated material will be delivered by ship to a nearby cement works as raw material. Around 10% of the material will be used for a 228m-long lake embankment on the side of the tunnel portal towards Biel, where there is not enough space for a second track.
The project involves replacing a single-track line with the new double-track to eliminate the last railroad bottleneck on the Jura River line between Lausanne and Biel. The double-track tunnel was chosen because of the confined space between Lake Biel and the slope, where the N5 national road and the cantonal road also run.
The project also includes four escape tunnels connected to the safety tunnel of the N5 highway, a 114m-long viaduct for the N5 highway exit, two covered cuts at the two tunnel portals, and the redesign of 400m of the cantonal road on the Biel side. Once the work has been completed, the existing railroad line will be dismantled and redesigned.
