Doggerland Offshore, in collaboration with its partner Abeko Marine, successfully completed a major capital dredging project in the UK in early June 2023.
In November 2022, we won a public tender as main contractor to dredge a deeper channel leading to the Grimsby GRT terminal. This channel facilitates the docking and (un)loading of larger car carriers even during low tides, thereby improving the operational efficiency of the Grimsby port.
Although we initially planned to dredge with clamshell buckets on our backhoes, we swiftly realized that the dredged material was much stiffer than expected and required the use of a normal bucket (5,5 m3 water volume). In total, we worked in 24-hour operations with the backhoes Abeko Server 1 and Abeko Server 2 (both equipped with a Hitatchi 1200 triple), over these months, dredging over 500,000 in-situ cubic meters of stiff clay to dumpsite HU-080. The dumpsite was about a 45-minute round trip away by sea. A short period also Abeko Server-3 was on site (equipped with a Komatsu PC-800)
The project came with its fair share of challenges. The site in the Humber Estuary is highly exposed to wind waves and swell. Since towing was prohibited, the tugs had to take the barges alongside. Combining this with strong currents of up to 5 knots due to the high tidal range of over 6 meters, sailing with the barges to the dumpsite was not an easy task for the tugs and was very demanding. To maintain control over the loaded barges in these currents, we used relatively small split hopper barges of 450 m3 (2x) and 600 m3 (2x), in combination with 30-ton bollard pull shallow draft tugs.
The dredging spread had to be removed sometimes multiple times a day out of the channel to make way for commercial vessels, and we were impressed by the tugboat crews who needed all their skills!
Dredging very close to the jetty and between the foundations piles, which requires a different pontoon and barge position, is much more difficult than normal.
During the work, we greatly benefited from the own propulsion systems and heavy spud systems of both employed backhoe dredgers. This made a significant difference in efficiently completing the job within these currents. We also employed a dedicated crew-transport and survey vessel equipped with a multibeam system to conduct daily surveys of the dredging works and the dump area.
The teamwork among all crew members, our staff, and the representatives of ABP was essential to the success of this project.
This project serves as an example of Doggerland Offshore’s and Abeko Marine’s shared commitment to performing projects efficiently, with a no-nonsense attitude, and by employing cost-effective solutions. The project was completed to the full satisfaction of our client, ABP, without a legal aftermath.
We are excited to witness the positive impact of our efforts on maritime operations at the Grimsby GRT terminal and look forward to more opportunities to collaborate in the industry.