In the course of the completion of the national road network, the missing link between Ingenbohl and Gumpisch along Urner Lake will have to be realized.
The core of the N4 New Axen Road consists of the bi-directional two-track Sisikon and Morschach Tunnels. The Morschach Tunnel is approx. 2.9 km long and is excavated by drill-and-blast from Ingenbohl. The Sisikon Tunnel is approx. 4.4 km long and is, due to the space restrictions in both portal areas, mostly excavated by drill-and-blast from the access at Dorni.
The tunnels are mostly driven through stable lime rock formations, structurally more unfavorable conditions with Palfris marl are expected only in the region of the Riemenstald Valley. Ventilation stations will be built on each portal.
Lombardi Ltd. is working for this project in a consortium called “INGE Axen”.
The services include the sections tunnel construction as well as the technical overall direction of the project with the following scope of performance:
- Technical coordination between the planners and the specialists;
- Design of the main project, detailed project and preparation of the bidding
- Preparation of documents for the implementation.