Milestone Achieved

During the night from Friday to Saturday, an important milestone was reached: the fifth tunnel element has been successfully placed on the riverbed of the Scheldt.

Controlled Immersion Operation

The successful placement was the result of a carefully planned immersion operation. Once the tunnel element was connected to the winches, Asterix and Obelix, our immersion catamarans, underwent a final inspection. The controlled immersion then began: using five ballast tanks, together larger than an Olympic swimming pool, the element was gradually filled with river water, while the teams guided it precisely into position via the winches.

Ballast System of Each Tunnel Element

• 5 ballast tanks over 6 metres high
• 500 metres of HDPE piping (Ø300 mm)
• Inlets and de-ballast pumps for each tank
• Manual butterfly valves and remotely operated slide gates
• Integrated leakage water system with automatic pumps
• Inlets of over 2,500 m³/hour and de-ballast outflow of approx. 300 m³/hour
• All systems centrally controlled from the IMMONTEC Command Unit

Precision on the Riverbed

The entire operation takes approximately 48 hours, with the immersion itself lasting 2 to 3 hours. On the riverbed, the element rests on specially placed support tiles, achieving millimetre-level precision even in flowing water.

We are proud of the entire team that made this possible once again. In two weeks, element 6 is scheduled for immersion! 👏

Would you like to be part of such unique and complex projects? Check out our vacancies and help us build the future.