On 1 August 2025, the New Lock has officially been declared as fully operational and as such is now entirely available for shipping traffic between the Westerschelde and the Canal Gent - Terneuzen.
With a length of 427 m, a width of 55 m and a depth 16,44 m, it is not only the largest of the three locks that constitute the Terneuzen lock complex, it is also one of the largest maritime locks in the world.
A complicated project
The construction of a large maritime lock encompasses a multitude of disciplines, such as concrete works, steel construction, road construction, revetments works, scour protection, hydraulics, electronics, automation and, last but not least, dredging.The New Lock Terneuzen has been built by the Joint Venture Sassevaart for the account of the Vlaams Nederlandse Schelde Commissie (VNSC), a dedicated organisation of the Flemish and Dutch authorities.
With the Belgian maritime contracting company DEME Group as one of the partners in the Joint Venture, this project has seen many vessels of its dredging fleet being deployed here.
Reclamation works
Miscellaneous dredging activities have been carried out throughout the entire construction period, but the first major operation started in 2019.This consisted of the reclamation of the area for the New Lock including the areas for the inner and outer lock heads.
Several of DEME's trailing suction hopper dredgers (TSHDs) have been deployed for this activity, such as the 13,700 m3 Lange Wapper and the newly built 15,000 m3 Bonny River for which it was its first major project.
Almost 1 Million m3 of sand has been pumped ashore as part of this activity.
The Bonny River pumping sand ashore, June - July 2019
Removing peninsulas
The Amazone arrives on the project site, 14 September 2023
From September 2023 to February 2024, a second major dredging operation took place.
This consisted of the removal of two peninsulas, one on either side of the lock complex.
These peninsulas needed to be dredged to make room for the access to the New Lock.
This operation represented a total amount some 3.5 Million m3 of different soil types.
Sand that was considered as suitable, was reused for a foreshore replenishment off the coast of Knokke in Belgium.
The remaining material was relocated in dedicated sites in the Westerschelde.
The leading role of this operation was played by DEME Group's 13,000 kW cutter suction dredger Amazone.
Furthermore, three TSHD's, the 5,400 m3 Pallieter and the 5,600 m3 Marieke and Artevelde, as well as a purposely built "split" pontoon have been used for this activity.
The work method was as follows: the Amazone dredged the peninsulas and pumped the material via the "split" pontoon to one of the TSHDs.
The TSHDs subsequently took care of the transport to either one of the relocation sites in the Westerschelde or to the coast of Knokke.
From the "split" pontoon, that was positioned at the Westerschelde side of the lock complex, it was possible to alternately use two different floating pipelines to direct the dredged material to a TSHD.
This configuration enabled to carry out the coupling of an empty TSHD even before the prior one had completed the loading operation, allowing to save a lot of time.
1. The Artevelde, Pallieter and the "split pontoon" in the outer harbour, 7 November 2023
2. The Amazone dredging the northern peninsula, 11 January 2024
Profiling the waterbed
Once the Amazone had completed the first stage of this operation, i.e. the peninsula at the Canal side, a plough dredger was used to level out the waterbed.
On the Westerschelde side, it was efficient at a certain time to demobilize the Amazone and have the remaining layer of material, the so-called "spill layer", dredged directly by a TSHD.
This operation took mainly place during February 2024 and involved the Marieke as well as the DC Orisant that was chartered from its co-owners, i.e. Group Decloedt and Reimerswaal Dredging.
Finally, also on the Westerschelde side a plough dredger was deployed for levelling.
The plough dredger Lotus and the DC Orisant in the outer harbour, February 2024
Deepening and maintenance dredging
Besides these two major operations, significant dredging work was also required to deepen the outer and inner harbour basins, which form the entrance to the New Lock, on the northern and southern side respectively.
After completion of this task, regular maintenance dredging needed to be carried out to keep these basins at the required depth during the construction period.
For both the deepening as well as the maintenance, amongst other several TSHDs were deployed.
Other dredging works
For various other tasks during the construction, a wide range of mechanical dredgers, such as grabs and backhoes have been used.
This included DEME Group's powerful backhoe dredgers Samson and Peter the Great.
These tasks comprised amongst other the removal of subsoil structures, preparation of the waterbed for the installation of scour protection and operations in confined areas.
1. The grab hopper dredger Optimist, 10 October 2023
2. The Peter the Great, 26 January 2024
A final dredging campaign
Just prior to the trial program of the New Lock, from February until May 2025, a final dredging campaign was carried out in the northern harbour basin, know as the Westbuitenhaven, at both entrances of the New Lock and in the lock chamber itself.
This operation was organised jointly by VNSC and North Sea Port, the port authority responsible for both the port of Terneuzen and Gent, but also for Vlissingen at the other side of the Westerschelde.
For this dredging campaign VNSC / North Sea Port has chartered Baggerbedrijf de Boer, internationally known as Dutch Dredging, which used its TSHDs Lesse (2,300 m3) and Mahury (1,859 m3) as well as the plough dredger Rayador to do the work.
1. The Lesse and the Rayador in the Westbuitenhaven, 7 February 2025
2. The Mahury in the New Lock, 1 May 2025