The first of 90 tunnel elements has been lowered into the trench for the 18km Fehmarnbelt Tunnel, set to be the world’s longest immersed tunnel.
Key Takeaways
At 18km, Fehmarnbelt will be over 3x longer than the current record-holder, the 5.8km Transbay Tube in San Francisco.
79 Standard Tunnel Elements (217m each, 33,000m3 concrete, displacing 75,000 tons of seawater) plus 10 Special Elements and 1 closing joint = 90 total immersion operations.
The trench reaches 45m below sea level; elements are prefabricated on land, floated via basins to a working port, then towed and lowered into position.
The tunnel carries a 2x2-lane highway and 2x1 railway, completing the high-speed rail link between Stockholm and Hamburg.
Three separate civil contracts cover portals/ramps (TPR), dredging/reclamation (TDR), and the immersed tunnel itself (TUX), with contractor Femern Link Contractors executing TUX.
