A 'dive' into the past and future

The marine and underwater world holds no secrets for DISA International. The specialist in pioneering underwater solutions contributes to the most challenging projects worldwide. The GWW Yearbook is a good time to look back at a number of projects DISA completed in 2021-2022, but also to look ahead to the future. After all, the schedule is already pretty full for the coming years.

"Since 2003, our international customer base has relied on our revolutionary marine and underwater solutions," said Didier De Graaff, Managing Director of DISA International. DISA has its roots in Civil Underwater Construction and shipwreck removal. "The knowledge we have accumulated over all these years in the fascinating underwater world also proved to be very cross-applicable. With our Civil Construction Department, we have been providing underwater services for the construction, repair and maintenance of a wide variety of infrastructure projects since 2005." About three years later, the offshore branch was established: C-Ventus, now a well-known name and a dedicated service provider with specialist knowledge in the field of offshore wind farms. 

OpenIJ

A great example of a project in which DISA's pioneering underwater solutions and expertise have added great value is the construction of sea lock OpenIJ in IJmuiden. "On July 12, 2021, we reached our final milestone after a five-year period, completing all underwater work required for the construction of this extensive infrastructure project," says De Graaff. "In total, we spent 95,190 working hours and 22,550 diving hours on this project with 187 DISA appointees ranging from dive supervisors, divers, foremen and project managers. As DISA, we are justifiably proud to have been a part of this amazing and globally unique project."

Brunsbüttel

A new lock complex is being built by W&F and BAM in Brunsbüttel, Germany. With more than 30,000 passing ships a year and 100 ocean-going vessels a day, the complex is the busiest shipping route in the world. "The hundred-year-old lock complex can no longer handle these crowds," De Graaff knows. "That's why a new lock, the fifth, is now being built. More or less comparable in complexity and size to the sea lock in IJmuiden. Here, too, we are providing a large number of underwater services to ensure the construction goes as smoothly as possible and to prevent damage to the existing locks. A wonderful project in a historic location."

Blankenburg Link

Starting in 2024, the new A24 Blankenburg connection will connect the A20 near Vlaardingen with the A15 near Rozenburg. The new highway is partly below ground level and is also largely built under water. A monster job for DISA International, mostly at great depths below water level. "At peak times, we assisted contractor combination BAAK with as many as 180 culverts," says Marc Dröge, General Manager of DISA Civil Constructions. "With the Blankenburg connection, the law of large numbers applies. Apart from the enormous quantities, the big challenge was particularly in the great depth of up to 32 meters below the water level. We came up with all kinds of clever solutions to deal with this efficiently, such as diving with different gas mixtures and deploying surface decompression so that our divers could stay underwater for longer periods of time."

Green Arch

With earth walls, a half-sunken tunnel through the Lage Bergse Bos, noise barriers and sound-absorbing asphalt, the energy-neutral A16 Rotterdam will be one of the best fitted national highways in the Netherlands. It is also an extremely tightly directed project. For the construction of the 2.2-kilometer-long Rottemer Tunnel, for example, work is being carried out in eleven construction pits simultaneously. With more than 100 culverts, DISA International is making a significant contribution. Nevertheless, there is a serene calm under and above the water. "Besides the structured diver deployment, combination De Groene Boog praises our proactive attitude toward safe working. And we are quite proud of that as an organization, quite apart from the fine performance our divers deliver every day," John Penson, Operations Manager of DISA Civil Structures, proudly said.

Offshore wind

C-Ventus has built a nice reputation in contributing to offshore wind farms.     

"From 2008, for example, we provided the necessary assistance with the construction of Offshore Wind Farm Egmond aan Zee, the first Dutch offshore wind farm in the North Sea off the coast at Egmond aan Zee. And we have never really 'left' since then, as we have been providing maintenance there on behalf of Shell for almost 15 years," says Paul van Tongeren, General Manager of C-Ventus. C-Ventus also had an important role in delivering the 70 foundations of the new Hollandse Kust Zuid wind farm. The wind farm delivered power to the Dutch grid for the first time this summer. Although the first rotating turbine is still in the testing phase, it is already producing power. Located some 18 to 35 kilometers off the coast between The Hague and Zandvoort, the wind farm should be fully operational by 2023. 

The above is just a sampling of the 37 projects DISA International has contributed or is contributing to over the past two years. "We stand for operational excellence, safety and transparency to provide the highest quality to our customers. Following the ISO accreditation, we achieved Step 3 on the Safety Culture Ladder in 2022. Step 4 is scheduled for 2023. And speaking of planning, we are already assured of great assignments for all our divisions in the coming years as well."