Afsluitdijk

Running from Den Oever in North Holland province to Kornwerderderzand in Friesland, the 32 km Afsluitdijk protects a huge area of the Netherlands from flooding. The project to upgrade the structure will see BAM PPP introduce a series of innovations across construction, design and process.

Construction

The key innovation for the Afsluitdijk project is the use of the XblocPlus, a concrete armour unit developed by BAM’s marine engineering experts, Delta Marine Consultants (DMC). The unit evolved from the original Xbloc, 400,000 of which are already in use to protect coastlines, dykes and breakwaters across the world.

Known as Levvel-blocs for this project, 75,000 will be deployed to give the dam the smooth, stable appearance required by the architect. DMC’s aim in developing them was to make even more efficient use of concrete by reducing the amount used as well as simplifying the placement process. The larger size of the blocks will create major savings in time and money.

Their design also includes a hole which increases stability by reducing water pressure under the blocks and is also used to lift and place them. Added safety is another key benefit as placement is carried out using a specially designed clamp with no people required to grab and release blocks during the process.

Design concept

Energy efficiency is built into the project with Europe’s biggest pumping station forming part of the dam to ensure it can disperse large volumes of water, with excess being drained from the IJsselmeer into the Wadden Sea.

Sustainability

The two large pumping stations at Den Oever will operate with very low energy consumption, will be fish-friendly and powered sustainably by 2.7 hectares of solar panels. The generated solar power will compensate the total energy consumption of the Afsluitdijk. Besides this energy efficient solution, there are additional benefits for the local ecology and wildlife.

A fish migration river is being created which will enable fish to reach their natural spawning grounds and habitats with a key innovation being the installation of a fibre-reinforced plastic floodgate in the river.

Innovation process

An Integrated SPC/EPC management system will ensure regular collaboration between two project directors as well as efficient procedures.

The use of KPI dashboards deploying Microsoft PowerBI will mean management information is visualised for every part of the project and consolidated in a KPI overview.