Swiss Federal Railways (SBB) has announced that on September 3, renovation work would start on the Hauenstein Base Tunnel.
For the next 25 years, this initiative intends to maintain safe and effective rail operations throughout the tunnel.
The technological systems and the tunnel vault will both undergo renovation and renewal during the project.
Between 1912 and 1916, the two-lane, 8.134-kilometer-long Hauenstein Base Tunnel was constructed. It is a portion of the Basel-Olten rail route, which sees an average of 320 passenger trains and 100 freight trains daily.
Between 1980 and 1987, the tunnel underwent its last significant repair; since then, SBB has regularly performed selective maintenance and restoration work. Now, a significant revamp is necessary. All of the wires will need to be re-laid, and the tracks, including the rails, sleepers, and ballast, will need to be updated and replaced.
Additionally, the track drainage will be repaired and modified, the tunnel self-rescue systems updated, and technical systems like the Zeglingen ventilation shaft upgraded.
The project will be paid for through the federal government’s and SBB’s performance agreement, with an estimated cost of about 140 million CHF (146 million EUR).
Up until the fall of 2026, most of the work will be done at night.
Long-distance traffic may occasionally have earlier departure schedules and lengthier travel times as a result of necessary one-lane closures.
In 2024, 2026, 2027, and 2028, four tunnel-wide lane closures are also anticipated. Each of them will last for five weeks during the summer break so that SBB can update the tunnel tracks. Buses will run in place of the S9 trains during this time.
While SBB works on the switches, specific weekends will also see total closures. This work will necessitate significant schedule adjustments.