The maritime infrastructure works on and around the weir lock complex along the Lys in Harelbeke in Belgium have been officially delivered.

These infrastructure works in Harelbeke are part of the overall Seine-Scheldt project

These infrastructure works in Harelbeke are part of the overall Seine-Scheldt project

The ‘Leieland’ Joint Venture, a partnership between contractors Jan De Nul nv, Herbosch Kiere nv, Engie Fabricom nv and Aelterman bvba, was responsible for the design and execution of the works.

The 5-year project was commissioned by ‘De Vlaamse Waterweg’ (the Flemish Waterway Authority) covering the renovation and modernisation of the weir lock, waterway and environment alongside the river Lys in Harelbeke.

Jan De Nul nv and Herbosch-Kiere nv were jointly responsible for the civil engineering works, as well as for the general coordination of the project and all parties involved. Engie Fabricom was responsible for the electromechanical works, Aelterman bvba for the steel construction works.

The infrastructure works took place in the town centre of Harelbeke. Another impediment was that during the works the Lys could not be blocked for shipping. All this had a direct impact on the execution methods and project planning.

The project partners decided to install a temporary lock so that shipping would not be affected by the works. A temporary weir made sure there was no flooding during the works.

The new lock and weir were to be built at the same location as the old one to ensure the best possible nautical and hydraulic design. In other words, the construction could only start after the installation of the temporary infrastructure and the demolition of the old infrastructure.

Next to the new weir lock complex, the Joint Venture built a pumping station with two turbines. When the water flow is in surplus, the turbines will generate energy. In dry periods the pumping station can pump water to the upstream water level. The expected energy production is higher than the energy consumed by the weir lock complex so that the complex can be considered energy-neutral.

These infrastructure works in Harelbeke are part of the overall Seine-Scheldt project, which improves the waterway link between the Seine basin and the Scheldt basin. Thanks to some large-scale infrastructure works in France, Wallonia and Flanders, inland navigation vessels up to 4,500 tonnes will be able to sail between Paris and Antwerp. These infrastructure works include the renovation of locks, weirs and quay walls, the deepening of canals and the excavation of new ones and the raising of bridges.

The scope of the infrastructure works executed by the Joint Venture ‘Leieland’

* Demolition of old infrastructure

* New lock (230m long, 12.5m wide x 4.70m water depth)

* New weir (2 weir segments, each 12.5m wide)

* Pumping station with turbines

* Fish ladder

* Quay walls (2km)

* Dredging works

* Construction of the new steel bridge Hogebrug (80m and 1,000 tonnes), Bloemmolenbrug (movable bicycle bridge), Banmolenbrug

* Sewage system, district heating and road construction works


Jan De Nul Group
Jan De Nul Group provides complex offshore services for both the fossil and renewable energy sector worldwide including large-scale dredging and land reclamation projects.

Herbosch Kiere has over a century’s experience in port, river and marine works. The workshop located in the Port of Antwerp is the ideal base to carry out works across the world. Herbosch-Kiere permanently invests in specific equipment such as ships, jack-up platforms and both floating and non-floating equipment.

Over the years, Herbosch-Kiere has expanded its activities with the execution of environmental works, the construction and operation of landfills and soil remediation works.

Engie Fabricom nv
Engie Fabricom has over 60 years of experience with and know-how of technical installations in electricity, instrumentation, mechanical engineering, automation and corresponding services. A few examples are: A11 bridges, Evergem lock, hydropower plants Albert Canal and the renovation of the Mexico bridges in Antwerp.

Aelterman bvba
Aelterman bvba is a familiar name within the steel construction industry. The company is specialised in the production and installation of steel bridges, lock gates, offshore structures and similar heavy welded constructions, both in Belgium and abroad. The company has recently provided its services to the second Scheldt bridge in Temse, Pylon R4 South in Gent and London Bridge.

By Jake Frith