The challenge

Up until this day, the Oosterscheldekering still speaks to anyone’s imagination. The impressive storm surge barrier, which is part of the Deltaworks, is truly one of the most impressive hydraulic constructions in the world. When the water level exceeds the regular sea level by three meters, the sliding doors close and the Zeeland Delta remains protected against extremely high water. The Deltaworks consists of several other dams, harbours, locks and bridges. Despite the robust constructions, all these structures require continuous management and maintenance. Adequate repairs of malfunctions and perfect maintenance are essential for flood risk management, traffic and shipping.

Repair and maintenance

Rijkswaterstaat, the Dutch Directorate-General for Public Works and Water Management, has outsourced the maintenance of the Oosterscheldekering, with all adjacent locks, jetties, quays, bridges and viaducts, to civil contractor VolkerWessels. The project is executed based on a UAV-GC performance contract. The most striking maintenance is the preservation of the 65 pillar structures, 32 integrated sliding doors and 2 level measuring stations. Due to the continuous influence of seawater on the construction, the steel must be coated regularly. Besides this, the integral maintenance and repair of all electrical and mechanical installations and the maintenance of the structures, roads and waterways has to be carried out as well.

Facts about the Oosterschelde storm surge barrier

  • The barrier has a length of 9 km (3 km of sliding doors) and is designed to withstand an extremely high water level that statistically occurs once every 4000 years;
  • The pier structures are 30-40 meters high, with a weight of up to 18,000 tons. They are made of concrete and have been filled with sand after placement;
  • The sliding doors are approximately 6-12 meters high and 42 meters long, each with a weight of 260 to 480 tons.
  • The sliding doors are set in motion with two hydraulic cylinders. The closing of the gates takes approximately 82 minutes.

Our activities

Rijkswaterstaat PPO has awarded Walhout Civil a multi-year contract for providing technical advice. Our activities include:

  • Forming customer specifications (KES)
  • Forming demand specifications (VSE / VSP)
  • Collaboration with managers and contractors
  • Technical development and risk analysis
  • Coordination of studies and researches
  • Reviewing designs and plans

Copyright images and videos: Rijkswaterstaat, Ministry of Infrastructure and Water Management.