Tender Details: Excavation and reinforcement of a new pressure tunnel (pressure shaft renovation) connecting the
Bilsten compensation basin and the Altendorf power plant.
- Authority: Swiss Federal Railways SBB, Infrastructure - Purchasing (Bern site).
- Deadline for Bids: Submissions must be made by 30 April 2026 (some notices indicate a final deadline of 4 May 2026).
- Project Context: The Etzelwerk plant is a critical pumped-storage facility solely owned by SBB. The modernisation includes updating technology such as replacing turbines and penstocks to secure the plant's long-term operation.
Interested parties can access full documentation through SwitzerlandTenders or official SBB Procurement channels.
This open procedure has been launched for the excavation and reinforcement of a new pressure tunnel between the existing Bilsten compensation basin and the Altendorf power plant (Lot 203), as part of the modernisation of the Etzelwerk hydropower plant, originally constructed between 1932 and 1937.
The plant exploits the elevation difference between Lake Sihl and Lake Zurich and supplies approximately 10% of Switzerland’s railway electricity demand.
The works foresee an initial 85 m section with a 4% gradient excavated using a roadheader. Subject to sufficient rock quality and overburden, excavation will continue with a TBM over approximately 2,085 m, with gradients ranging between 4% and 33%.
Tender documents are available here.
Client: SBB, Olten.
Tel: +41 000000000 | Email: hans-juergen.markert@sbb.ch
TED notices:
https://ted.europa.eu/en/notice/-/detail/72227-2026 (OJ S 022)
https://ted.europa.eu/en/notice/-/detail/56432-2026 (OJ S 017)
06/26.
