The importance of the Afsluitdijk

The importance of the Afsluitdijk

The Afsluitdijk is from great value for the Netherlands and is being used for safety, traffic across the roads and waters, cultural history, recreation and more. Because of these reasons, it is vital to upkeep the dyke.

Reasons of reinforcement

The climate is changing. As a result, the sea level is rising and extreme weather conditions will occur more frequently. The dyke must then still be able to protect us against flooding. The response: to strengthen the dyke along its entire length and reinforce all of its components.

Furthermore, we use the sluices at Den Oever and Kornwerderzand to discharge excess water from the IJsselmeer into the Wadden Sea. When the water level in the Wadden Sea is low, the sluice gates can open and allow the water of the IJsselmeer to flow into the sea. A growing problem, however, is that they are increasingly unable to discharge enough water. The response: to install pumps in the sluice complex at Den Oever.

A once-in-a-ten-thousand-years risk

The Afsluitdijk has to offer protection even in severe weather conditions, for example the coincidence of a spring tide and an extreme north-westerly storm. In that event, the water is driven high against the dyke and waves crash over it. The dyke must not succumb to that pressure. The Afsluitdijk has to be able to meet the once-in-a-ten-thousand-years criterion, which means it has to be able to withstand any combination of high water and waves with a risk of occurring once in 10.000 years. In other words, it has to be able to cope with what is known as a superstorm.

Reinforcing the dyke

The outer side of the dyke (the side facing the Wadden Sea) will be covered with new cladding which is strong enough to withstand the waves that beat against the dyke during a heavy storm. The plan is to make the dyke overflow-resistant. This means that the entire dyke will be designed in such a way that water can flow over it during a heavy storm, without causing problems. The inner side of the dyke (the side facing the IJsselmeer) will be able to cope with the encroaching water.


The Afsluitdijk separates the Wadden Sea from the IJsselmeer, 2 areas of unique natural beauty. We will take account of that during the preparation and execution of the project. For example, water birds rest and eat in the shadow of the dyke. At some locations, we will not be working all year round because of the animals. Seals also need peace and quite and we will respect that by setting limits for the noise level during the work.

Spatial quality

The Afsluitdijk has great value in cultural-historical terms and for tourism. The dyke is an icon of the Netherlands’ constant struggle against water and an international calling card for the Dutch hydraulic engineering sector. The dyke was designed by the renowned engineer Cornelis Lely. The monument at the site of the final section to be filled was designed by the architect Willem Dudok. The Afsluitdijk also has an important military history. The government will ensure that the area’s unique values are preserved, as far as possible, during the reinforcement of the dyke.

Cooperation internationally

Rijkswaterstaat works across borders with neighboring countries and international partners also facing challenges when it comes to water management. We exchange knowledge and experiences globally about dike reinforcement and the preservation of nature. This creates a strong international network of partnerships. It also leads to smarter and more effective solutions for everyone.

Cooperation with the region

Rijkswaterstaat’s primary responsibilities during this project are for ensuring the dyke's safety and for water management. The central government and regional authorities have also formulated ambitions in areas such as renewable energy, nature development, recreation and tourism. These ambitions have led to numerous initiatives, including the construction of a recreational cycle path on the Wadden Sea side of the dyke, improvements to the public space around the Afsluitdijk and the upgrading of facilities.

Furthermore, there a number of pilot projects with renewable energy, an innovative art project with innovator Daan Roosegaarde, the construction of a fish passage and a fish migration river that will allow fish to swim from salt to fresh water. Regional authorities are taking the lead in many of these initiatives and will flesh out the details in consultation with the central government. Together, we are building a safe, sustainable, attractive and future-proof dyke.