The contract award marks the start of tunnel work on the line and includes the planning and construction of the Lysaker-Fornebu tunnel and cross passages, as well as the excavation pits and rock shafts for the Flytårnet and Fornebuporten stations.
Implenia said it won the contract due to its expertise, competitive offer and its compliance with the contract’s stringent environmental and climate-protection stipulations. It will be signed when the 10-day objection period has lapsed.
Grete Tvedt, project manager at Fornebubanen said: “Those companies that invest the most in alternative fuel technologies and contribute to the electrification of machines and systems performed best in this [bidding] competition. The focus on sustainability seems to produce good solutions, not only in terms of environmental and climate protection, but also for the entire project. We are looking forward to a good collaboration with Implenia on this large and important tunnel project.”
Anticipated for a May 2021 start, the tunnel is expected to be driven by drill and blast, and secured by rock bolts and shotcrete, with grout injection where needed. The alignment is expected to comprise typical Oslo area geology, including shale, tuberous lime and volcanic passages. The six stations on the line will be located at between 12-43m below ground level.
Located on the western edge of Oslo, the US$1.86bn Fornebu line will run for 8.15km from Majorstuen to Fornebu and have six stations: Skøyen, Lysaker, Vaekerø, Fornebuporten, Flytårnet and Fornebu. It is the most significant metro development in Norway since the large metro developments on the eastern edge of Oslo in the 1960s and 70s.
The Lysaker-Fornebu tunnel is scheduled for completion in autumn 2023; the entire line should be completed by 2027.