Project description
The new Weser Tunnel is part of the “Weserquerung”, a major infrastructure project in Bremen, Germany. It involves the construction of a new immersed tunnel beneath the River Weser as part of the A281 motorway. The new route is designed to create a direct connection between the northern and southern parts of Bremen, easing congestion on the current road network and significantly improving traffic flow.
The tunnel will be approximately 1 kilometre long and consist of six immersed tunnel elements and one cut-and-cover section. The elements range in length from 113 to 125 metres and are 23 metres wide. The dimensions of the standard tunnel cross-section vary due to the integration of recesses in the ceiling and walls for breakdown bays, ventilation, and emergency phones.
The elements are constructed in a dry dock in Bremerhaven. After completion, they are floated out and transported over a distance of 60 kilometres to a temporary mooring location. Once all necessary components have been installed, the elements are immersed and positioned at their permanent location.
Tunnel construction began in 2024. MH Poly, in collaboration with Immontec B.V., provided the immersion engineering for all temporary structures.
Project activities
MH Poly designed all temporary structures required for the immersion of the tunnel elements, from concept design to detailed engineering.
This included:
- Current control system: to manage river currents during immersion.
- Temporary supports: to provide temporary support for the tunnel elements.
- Deck layout: configuration of the deck for transport and immersion operations.
- Ballast system: for the controlled sinking of the elements.
- Realignment system: for accurate positioning of the tunnel elements.
- Mooring system: for temporary securing of the elements.
- Anchor and winch system at the immersion site: to hold the elements in place during immersion.