Both contracts for tunnel works on the Drammen-Kobbervikdalen section of the Vestfold rail line in Norway have been awarded to local contractor Veidekke.

Drammen-Kobbervikdalen rail tunnel on Vestfold scheme

Client Bane NOR selected Veidekke for the engineering, procurement and construction (EPC) contracts to excavate the single-tube, double-track 6km long Lot UDK 01 main rock tunnel for a contract value of NKr1.96 billion (US$213 million), and the UDK02 contract for two shorter soft ground tunnels and a section of cut-and-cover work for a contract of NKr1.83 billion (US$200 million). Planning work, including the integration of a building information modelling (BIM) system, is underway towards start of construction of the near total 11km of tunnelling. Bane NOR began procurement in mid-2018 with an aim of getting both lots underway by end of 2019, but tender negotiations took longer than anticipated.

The 123m² rock tunnel will be lined to 93m² in finished cross-section. The contract also includes adits and two emergency evacuation tunnels, each with a cross-section of 25m². Lot UDK01 is due for completion in 2024.

Award confirmation between Bane NOR and Veidekke

The shorter Lot UDK02 tunnels has a contract value almost as much as UDK012, but complicated local geology with clay or sand over solid glaciofluvial deposits requires challenging soft ground excavation and a cut-and-cover box section. Main construction is due to start in April 2020.

The Drammen-Kobbervikdalen section of the rail line is situated south west of the Norway capital city Oslo and comprises the next stage of capital investment improvements on the Vestfold line.

Norway rail company Bane NOR has launched the procurement process for tunnel works in the next phase of improvements to its Drammen-Kobbervikdalen Vestfold line south west of Oslo. Works include a 6km long rock tunnel under Contract UDK 01 and a cut-and-cover tunnel in two sections of 370m and 275m long for Contract UDK 02.

Drammen-Kobbervikdalen rail tunnel

The first lot in the procurement is the UDK 02 cut-and-cover tunnel for which Bane NOR issued a tender notice with a deadline of 20 August for submissions or requests to participate in the competitive dialogue process. Bane NOR aims to have the EPC (engineering, procurement, construction) contract signed by June 2019 for work to start in August. The aim is for construction to be completed by March 2023.

Bane NOR said the 320m tunnel will be excavated to depths of 11-21m and, in parts, will be below groundwater level. The geology along the alignment is either clay or sand over solid glaciofluvial deposits of sand and gravel with fines of less than 10%. The 275m long cut-and-cover tunnel will be excavated in a stretch of loose deposits over the glaciofluvial base.

A tender notice for the UDK 01 6km long drill+blast rock tunnel is to be released in September this year (2018). A signing of the EPC contract is planned for August 2019 with construction work to start immediately.

Aerial view of Drammen

The single rock tunnel is to have and and excavated and finished cross-section of 123m² and 93m² respectively. The works package will also include two cross tunnel adits of 60m² at Austadvein and Danserud plus two further dedicated 25m² evacuation tunnels. Blasting volume on the contract is to total some 938,000m³.

The Drammen-Kobbervikdalen project will create a double-track line from Drammen along the Kobbervik valley and will include two new stations to be built at Drammen and Gulskogen.

The community of Drammen approved the rail link plan in April this year (2018) as part of the National Transport Plan. It is being developed using BIM (building information modelling) and is to be completed by 2025.