Works have begun on the much-awaited Fehmarnbelt Tunnel, connecting Denmark and Germany. The 18 km long tunnel will descend to a depth of up to 40 m beneath the Baltic Sea and will be the world’s longest immersed tunnel for road and rail.
Officially called the Fehmarnbelt Fixed Link, the tunnel is one of Europe’s largest infrastructure projects with a construction budget of over €7 billion ($8.2 billion). In comparison, the 50 km long Channel Tunnel completed in 1993 cost the equivalent of $15.5 billion in today’s value.
Although longer than the Fehmarnbelt Tunnel, the Channel Tunnel was constructed using a boring machine. In contrast, the Fehmarnbelt Tunnel will comprise of hollow concrete segments cast on land, sunk into their final position on the seabed, and linked together to form the tunnel.
The Fehmarnbelt tunnel is an epitome of innovative design by challenging the existing tunnel building standards. Its pioneering longitudinal ventilation system and state-of-the-art safety and security features improve the overall functionality of the tunnel.
Each tunnel element will weigh 73,000 tonnes and will be hollow and sealed with bulkheads in order to float in the water. A total of 79 individual elements and ten special elements will be assembled to complete the tunnel.
The tunnel will have a four-lane motorway and a twin track-electrified railway to connect Rødbyhavn in Denmark with Puttgarden in Germany. It will serve as an alternative to the current ferry service between the places to reduce the crossing time from 45 minutes to just seven minutes by train and ten minutes by car.
It will also cut short the train journey between Hamburg and Copenhagen from about four and a half to merely three hours.
The project is expected to move into the actual production stage of the tunnel sections by 2023. It is expected to be constructed in 8.5 years, with an opening slated in 2029.