National Dutch water authority Rijkswaterstaat announced its intention to contract joint venture Levvel for the reinforcement of the 32 km long closure dam Afsluitdijk, the Netherlands.

Joint venture Levvel (in formation), comprising of Dutch contractors BAM and Van Oord, Dutch consultant Rebel Valley and Dutch pension fund PGGM, will be responsible for designing, building and pre-financing the project. In addition, this consortium will be responsible for maintenance for 25 years.

dws-rws-new-afsluitdijk-design-350px  Impression of the new shaped dam that will be overflow-resistant.

Basic flood protection requirements
In 2015 the Dutch government initiated a 850 million euro master plan for a complete reinforcement of the closure dam as its 80 years old seaside slope is no longer strong enough to meet the current flood protection standards.

The master plan calls for a reconstruction as an overflow-resistant dam. The only requirements set by Rijkswaterstaat is that the design has to meet a flood protection standard of 1:10.000 years and a maximum overtopping of 10 l/s/m.

A more detailed design will be determined in a later stage in close consultation with the contractor. This creates posibilities to include the latest innovations and cost-effective solutions.

Combination price and quality
Rijkswaterstaat selected the tender by Levvel on the basis of a combination of price and quality, also called Most Economically Advantageous Tender (MEAT). MEAT helps to make better use of the innovative strength and creativity of the market.

Rijkswaterstaat has, among other things, assessed the plans of the market parties on the criteria 'satisfied end-user', 'satisfied operational manager' and 'satisfied environment'.

The master plan also includes the construction of a 5 km long artificial fish migration river and the construction of a new pumping station. With a capacity of 400 m3/s, the station will be the biggest in Europe.

dws-rws-new-afsluitdijkfish-passage-350pxOne of the many new features includes a 5 km long artificial fish passage river.

Energy neutral
Next to flood protection criteria Rijkswaterstaat, wants to make the dam energy neutral.

Already existing energy supply stations along the dam that generate power, are an array of tidal turbines and a Blue energy pilot plant that generates electricity from the difference in salt concentrations between the fresh water on one side of the dam and the salt sea water on the other side. A plan for a 6,5 MW solar station is being studied.

Additional features
A real novelty for the new Afsluitdijk will be a 5 km long artificial fish passage. This passage will provide a connection so that migrating fish can swim freely between the Wadden Sea and the IJssel Lake.

Part of the Afsluitdijk are two discharge sluices at both ends of the dam allow to drain water from Lake IJssel during low tide at the Wadden Sea.

Due to the expected sea level rise, the discharge capacity of these sluices will decrease. Therefore an additional pumping station will be built with an initial capacity of 400 m3/s.

Construction works are expected to start in the autumn of 2018. In 2022, works on the Afsluitdijk will be completed.

This news item was originally published on the websites of BAM, Van Oord and Rijkswaterstaat (in Dutch only) and PGGM (in Dutch only).

Read also on this website
Fairylike light reflections at night on closure dam Afsluitdijk, the Netherlands, 22 November 2017
Ambitious 850 million reinforcement will make the Afsluitdijk a new icon of Dutch flood protection, 15 May 2015
Expertise: Enabling delta life
Country: the Netherlands

More information
BAM Group
Bunnink, the Netherlands
+31 30 659 89 88

Van Oord
Rotterdam, the Netherlands
+31 88 826 00 00

Programme office New Afsluitdijk
De Nieuwe Afsluitdijk
+31 58 292 58 20

Video explains the reconstruction of the New Afsluitdijk to ensure a safe, sustainable, attractive and future-proof dam.