N05 Twann/Douanne Northern Bypass Tunnel
Client / Awarding Authority
Federal Roads Office (FEDRO/ASTRA), Infrastructure Filiale Estavayer-le-Lac, Switzerland. Tel: +41 58 461 87 11.
Winning Contractor(s)
Not yet awarded (open procedure; deadline 24 April 2026).
Project Scope
Environmental engineering services (RIE) covering the detailed design phase and environmental supervision (SER) during tendering and construction for the N05 Twann northern bypass.
The contract includes development and integration of environmental mitigation measures into the final design, and monitoring compliance with Swiss environmental regulations relating to noise, groundwater, soil and emissions. The services also cover coordination with existing N05 infrastructure between Twann and Wingreis, including integration of a new partial interchange and connection to the existing Ligerz (Gléresse) tunnel.
The bypass scheme forms part of the strategic upgrade of the N05 corridor along Lake Biel, aiming to reroute through traffic away from the lakeside communities.
Tunnel Characteristics
- New road tunnel, approximately 1,925 m long
- Drill-and-blast excavation anticipated (typical for Swiss highway tunnels)
- Connection to existing Ligerz (Gléresse) tunnel
- Includes portals, safety systems and integration with national road standards
Contract Value
Not stated.
Duration
Services expected to run through to 31 December 2031.
Location
Twann-Tüscherz, Canton of Bern, Switzerland.
Click here for tender documents. https://www.simap.ch/fr/project-detail/7cd9135a-0a18-4e9f-8421-51b7ef58181d?lot-id=null
See https://ted.europa.eu/en/notice/-/detail/160206-2026 , OJ S 047. Ref. no. N05.70 MP-080012. 12/26.
