Fehmarn Belt: Under-Sea Tunnel Construction
Construction on this large project has begun: The Fehmarn Belt tunnel aims to close a gap in the Northern European rail network and will shorten the connection between the major cities of Hamburg and Copenhagen. The civil engineering work under the Baltic Sea will be the largest of its kind in the world.
It will take trains a mere seven minutes to cross the 18-kilometre-long tunnel, connecting Puttgarden on the German island of Fehmarn and Rødby on the Danish island of Lolland. Travelling between Hamburg and Copenhagen is anticipated to take less than three hours thanks to this link under the Baltic Sea. Until now, trains on this route have had to cross the Baltic Sea by ferry or take detours across the mainland.
The four-tube structure will be provided with two tubes for cars and two single-track electrified tubes for passenger and freight trains. There will be a Train Control Centre (TCC) in Copenhagen to monitor railway traffic.
The tunnel will be approved for speeds of up to 200 kilometres per hour. It will be equipped with a derailment protection system and emergency escape paths. Emergency exits will also be provided every 110 metres. The Fehmarn Belt tunnel will be the longest immersed tunnel for rail and road traffic in the world. The individual tunnel elements will be manufactured and sealed to make them watertight in a specially built factory in Rødbyhavn, Denmark. From a working harbour to be newly erected the elements will then be towed to their appropriate location, lowered one after the other into a trench on the seabed and connected to each other on-site. The Fehmarnbelt Tunnel will consist of 79 elements, each 217 metres long and weighing 73,000 tonnes. In addition, a total of ten special elements will be installed at intervals of about two kilometres, equipped with a basement for operating and maintenance equipment. The sea trench is to be up to 60 metres wide and 16 metres deep; the deepest point will reach 30 metres below the water surface.
Denmark is in charge of planning, building and maintaining the tunnel and will finance the Euro 7.1 billion (as of 2015) project with support from the EU’s “Connecting Europe Facility” fund. Germany will finance its own road and rail hinterland connections.
According to the current planning, the project is set to be completed in 2029. On the Danish side, construction of the working port has been underway since mid-2020, and work on the production facility for the tunnel elements already began in early 2021. To this end the state-owned Danish project company Femern A/S has signed contracts with two construction consortia: the FLC consortium is responsible for the immersed tunnel, the production of the elements as well as the tunnel portals. Members are, among others, Vinci (France), Waiss & Freytag, Max Bögl (Germany) and CFE (Belgium). The Dutch consortium FBC is responsible for the excavation and construction of the working port. Other contract packages which have not yet been awarded include the mechanical installations such as ventilation, lighting or safety systems.