The afsluitdijk had to be renovated. This would make the afsluitdijk future-proof. The project would be completed in 2021 or 2022.

The sluice gates that allow the water to go back and forth have to be customized and meet a variety of conditions, which depend, for example, on the conditions of the water. Incorrect and incomplete data were entered about water levels and wave heights. As a result, the design of the locks was incorrect and they had to be redesigned. This had been known for some time, but it was not clear how much delay this would cause and how expensive this error would be.

In any case, the renovation will take three years longer than planned and will probably cost hundreds of millions more due to this error. The knowledge center Deltares has now provided the correct data and corrected the error, so now the proper design can be made. Additional money will be taken from the Delta Fund to finance the project.