Our field of expertise

Outfitting the barge

 

The Fehmarnbelt Tunnel is a large-scale, long-term infrastructure project where Saltwater provides on-site support in Denmark. Once completed, it will be the world’s longest immersed tunnel at 18 kilometers, connecting Rødby (Denmark) with Puttgarden (Germany) and accommodating both rail and road transport. Scheduled to open to the public in 2029, the tunnel represents a major step forward in enhancing Europe’s cross-border connectivity.

 

A project of this scale requires extensive outfitting to ensure all equipment is available, functional, and suited to demanding technical conditions. One key part of our contribution, commissioned by FLC, was outfitting the maintenance barge, designed to service the tunnel-laying equipment. This included integrating drydock-like structures on both sides of the barge.

 

Engineering watertight reliability

Saltwater was responsible for the design and engineering of the drydock doors, including the production of detailed construction drawings. Similar to the construction of the doors we previously designed to be used on rock barges, these limpet dam drydock doors were immense in size and very heavy. Making our task more complicated were the additional requirements of these doors: they needed to be watertight and hydraulically operated, which meant tighter tolerances and a more complicated design, while still being robust.

 

Each door, measuring approximately 7 by 5 meters, was designed for structural strength and durability, ensuring watertight performance throughout the project. A system of hydraulically actuated locking pins secures the doors in the closed position, and a continuous rubber gasket around the perimeter ensures a tight seal. In contrast to the rock barge doors, these are hinged on multiple large pins to allow for smooth and stable movement.

 

Beyond the drydock structures, Saltwater also carried out topside outfitting of the barge. Although less prominent, this included critical features such as railings and walkways with integrated piping below deck, grillages for containerized equipment, draglines to support crawler crane mobility, and lashing points for safe transport.

 

While often overlooked, structural outfitting is essential to creating a safe and efficient working environment on board. Well-executed outfitting ensures functionality, safety, and user-friendliness often without being noticed, yet always essential.