N08 Sachseln Tunnel Maintenance Project – Increasing Tunnel Safety, Owner’s Engineer and Construction Supervision

The 5.2km long single tube Sachseln Tunnel has been in operation since 1997. It no longer meets current tunnel safety requirements. There are insuffiecient emergency ecape routes for users and the ventilation system only meets 30 % of the standard requirements. The tunnel will be retrofitted with a safety tunnel with 20 cross-links to the main tunnel. The ventilation system will be completely rebuilt. Exhaust air flaps will be installed as well as longitudinal ventilation (Saccardo-Stations at the portals). The entire operation and safety system in the existing tunnel will be replaced and the tunnel will be structurally repaired.


ASTRA, Zofingen Branch


Project monitoring: 2009–2020 IUB Engineering Ltd. in consortium

Construction period


Construction costs

CHF 130 million

Scope of services

Owner’s Engineer (OE) and construction supervision in the phases global maintenance concept to implementation/commissioning.

  • OE and external construction supervision for operation and safety systems through all phases
  • OE construction during project planning