The port areas of Ghent and Terneuzen are of great economic importance and the lock complex in Terneuzen provides access to these ports. The New Lock will ensure better access and a smoother connection from the Western Schelde estuary to the Ghent-Terneuzen Canal and beyond. With the arrival of the New Lock, which will replace the old Middle Lock, larger sea-going vessels of Neo Panamax size will be able to pass through. The capacity of the locks will also be increased, which will reduce the waiting time for inland vessels. The plan is that in 2022 the first ship will pass through the New Lock. The client is the Flemish-Dutch Scheldt Commission. Contractor combination Sassevaart (a collaboration between BAM, DEME, Van Laere and ENGIE), Iv-Infra’s client, will design, construct and maintain the New Lock for two years. “It’s very special that both the client and the contractor are a combination of Flemish and Dutch parties”, says Jeremy. “It creates a special vivacity, working with so many different companies and cultures.” 

“Neighbouring countries, Belgium and the Netherlands, share several similarities but the differences in the way in which work is conducted makes an international project like this one very interesting. In the Netherlands for example, the functional specification is generally provided, and much is left to the market. The Belgian government prefers to outline everything as in a traditional specification. For example, they have been building lock gates for years, based on earlier designs, with minor improvements, adopted from experience”, explains Jeremy. “To comply with the wishes set out by the tendering guidelines as much as possible, a combination of a construction method with the least possible inconvenience to inland navigation and the best possible maintainability of the complex were the main focuses. These were important EMVI criteria. Throughout the construction period, shipping and passage must continue as normal with as little hindrance as possible, and, of course, flood protection must be guaranteed in all phases. During the construction, a temporary passage canal has been constructed: the Kapitein Rooibos Canal. This will allow continued functionality of the current Middle Lock during the construction of the New Lock. To meet the strict requirements regarding maintenance, we will work with sustainable materials and allow for maintenance to take place with minimal hindrance for shipping and road traffic. The registration price is, of course, also important. To be able to make an offer as competitive as possible, the lock heads and the construction pits were compactly designed and the lock gates, only eight metres wide, are relatively narrow compared to those of comparable locks. In terms of strength this doesn’t pose a problem, however, it does present challenges in the floating stability. Ballast has now been added to the underside of the gate to achieve sufficient floating stability when floating the gate for maintenance.” 

In this project, Iv-Infra is responsible for the design of the four lock gates, the two bridges and levelling valves; everything including the operating mechanisms and maintenance facilities. The lock gates, a type of rolling gate, are rectangular steel constructions of 25 x 58 x 8 metres and weigh around 2,000 tonnes each. The gates are double-retaining and consist of two skin plates, with horizontal stiffeners on the outer side, a deck slab, a buoyancy tank and at the bottom, a horizontal truss frame. The outer ends of the gates are provided with vertical truss frame constructions. The lock gate is supported vertically on an upper trolley and a lower trolley, which run on rails in the chamber and in the lock head to open and close the gates. The upper trolley is connected to a winch system that is located in a cellar behind the lock gate. The gate is guided horizontally by means of six centrally positioned guide wheels. Under normal circumstances, these will provide a rolling guidance of the gate, but under extreme circumstances, such as the occurrence of large (vessel induced) waves, they will be pushed back in their suspension, leaving only sliding contact on the so-called overload blocks. 

The maintenance facilities consist of closure panels with which the gate recess can be converted into a dry dock: suspension yokes for hanging the gate, a collision beam around the closure panels for protection in the event of a collision and a bicycle/pedestrian bridge over the gate recess.

The levelling valves (two sets of four and one reserve) are placed in the two levelling valve houses. The gates are approximately 3 x 6 metres and are equipped with wheels. The valve bears its horizontal forces through wheels that run over rails arranged in the designated slots. Hydraulic cylinders above ground level are responsible for driving the mechanism. The hydraulic and electrical installations are located in cellars above the levelling valve house. 

“The tender was in 2016 and we have been working on the designs since 2017. The technical design is complete, and we are now busy with the implementation phase”, explains Jeremy. “A total of around twenty people from Iv worked on the project and in peak times around fifteen people at the same time. Our design team is part of a larger integral design team. Therefore, coordination is needed between all the different disciplines. Not only technical disciplines, such as geotechnics, hydraulics, civil engineering and mechanical engineering, but also the aspect disciplines such as management and maintenance, system integration, machine safety, cybersecurity, reliability/ availability and work preparation. This requires a well-coordinated team, a clear organisation and consultation structure, and the necessary tools.” For this project, it was decided to have the technical disciplines and aspect disciplines work together in a matrix organisation. The Relatics program includes all requirements, interfaces and risks that the designs must be tested against.

The New Lock in Terneuzen will have dimensions with which Neo Panamax ships can be passed. The lock will be 427 metres long, 55 metres wide and 16.44 metres deep. The chamber is to be the same size as the single lock chamber of the complex in the Panama Canal, for which Iv also provided the design. “I was involved as a technical project manager in the Panama Canal project. It was a huge challenge and a proper world project! Not only in terms of size and international co-operation but mainly because of the strict requirements that were imposed on the design at the time. Was this again the case? It certainly is! Many of the requirements are comparable, but each project has its own specific details. The requirements are certainly just as strict, it’s especially important in this project that during the realisation phase, the flood protection, availability for waterway traffic, the discharge capacity and the availability for road traffic are maintained. Again, a fantastic project of which we are pleased to be a part of.”  

The Kapitein Rooibos Canal (the temporary passage canal) is now in operation and the new lock plateau has been covered. The technical designs, steel and mechanical engineering are complete, and the gates and bridges are currently being constructed in China, under the supervision of the Sassevaart project team. When these are ready, they will be shipped to Terneuzen. Much still needs to be done before the first ship can pass through in three years’ time. Jeremy looks forward to it: “We have worked on so many locks, but it’s still a fantastic feeling when everything is finished, and it all works just as intended.”