The railroad line between Zug and Arth-Goldach on the eastern shore of Lake Zug is undergoing extensive renewal. The centerpiece is the construction of a new 1.7-kilometer double-track section near Walchwil.
Project description
For the new double track in Walchwil, the railroad line between Zug-Oberwil and Arth-Goldau was closed for 1.5 years. During this time, the entire line was renewed. The project included 9 new bridges and underpasses as well as a new tunnel. Around 40 bridges and underpasses as well as 34 retaining walls were rehabilitated. Furthermore, 7 tunnels were upgraded to double-decker standard. Around 12 km of the railroad track was completely renewed, including the substructure and drainage.
The Walchwil double track in detail
From Walchwil station northwards, the current single-track line was demolished over a length of 1.7 kilometers and a double track was built. In future, trains will be able to cross each other over a distance of just under 2.2 kilometers. This increases capacity and allows a denser timetable. Thanks to the track closure, the routing could be slightly optimized and fitted more ideally into the landscape. The Walchwil Hörndli stop was adapted to the new track position, the Büel tunnel was widened and a second bridge was added to the Sagenbach viaduct.
Structural maintenance and complete renewal of track systems
The maintenance of engineering structures and track systems comprised around 80 objects such as the Zug-Arth-Goldau railroad line, the town viaduct in Zug, various underpasses and overpasses as well as various culverts.
The existing railroad track (substructure, drainage, ballast, rails, sleepers) was completely and permanently renewed from Zug to Arth-Goldau. The engineering structures were repaired or newly built. Individual underpasses were enlarged. Due to the line closure, the temporarily closed track between Zug Oberwil and Arth-Goldau could be used for construction access.
Substance preservation at tunnels
The tunnels on the Zug - Arth-Goldau section were prepared for operation with double-deck trains. This required structural modifications to seven single-track railroad tunnels, which are around 115 years old: the catenary height and the space conditions were adjusted, and the high-voltage cables were relocated in cable conduit blocks.
Ecological measures
The project area along the Zug - Arth-Goldau railroad line - especially in the area of the Walchwil double track - is ecologically very diverse. Typical is a mosaic of different habitats: woods, margins, meadows, pastures, rocks and streams. The section Doppelspur Walchwil and the remaining stretch to Arth-Goldau have a rich reptile fauna. Particularly noteworthy are the numerous records of creeping snakes.
For the project Infrastructure Measures Lake Zug East, the temporary and permanent area requirements of valuable habitats were significant. Extensive ecological measures were taken to compensate for most of the impact on flora and fauna. A significant part of the measures was carried out before the start of construction, so that new habitats were already available at the time of the construction work.
Special features
Safety measures against natural hazards
The Zug-Arth-Goldau railroad line runs along the steep western flank of the Rufi mountain on land belonging to the municipality of Arth. In this area, the railroad line is exposed at various points to natural hazards such as landslides, floods, debris flows and block falls. In addition, there is a risk of destabilization of embankments during heavy precipitation. SBB had worked out protective measures together with external experts. These included the construction of protective dams, safety nets and the deepening of an existing catchment trench.
