One giant in place, seven more to go – precision beneath the surface

Immersing tunnel element Scheldt Tunnel – that’s the milestone we proudly achieved last night near Antwerp. The first tunnel section has now been placed with millimetre precision on the bottom of the Scheldt. A significant step in a complex project that demands technical expertise and flawless execution.

A giant placed on tiptoes

This first element measures an impressive 160 metres long, 46 metres wide, and 10 metres high, and weighs 60,000 tons. It travelled from the construction dock, through the Doeldok and Kallo lock, to the immersion site in the Scheldt.

Our trusted immersion pontoons – Asterix and Obelix – once again proved their value. With just 35 millimetres of clearance in the trench joint, the element was gently and precisely manoeuvred into position. Underwater millimetre work at its finest.

Precision and Timing: Challenges of Immersing Tunnel Elements

Immersing such a massive structure isn’t just a technical feat – it’s also a logistical puzzle. The strong tidal currents of the Scheldt impose strict operational conditions: calm weather, operations scheduled around slack tide, and carefully timed sequences.

A system of ballast tanks, hoisting cables, anchor wires and sealing profiles allowed the element to descend smoothly – as if placing a 60,000-tonner softly on its tiptoes.

Underwater Alignment with the ‘Kwispel’ System

Even on the riverbed, precision is essential. We used the so-called ‘kwispel system’ to fine-tune the position of the element – allowing millimetre-accurate alignment with the prepared foundation. Sometimes, even underwater, a little waggle makes all the difference 🐶.

Teamwork Behind the Scheldt Tunnel Success

This successful immersion is the result of meticulous planning, technical ingenuity, and seamless teamwork. Above and below water, every team member played a crucial role in making this milestone possible.

We’re proud of what we’ve accomplished – and ready for the next seven elements. One giant is in place. Let’s bring in the rest!

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