20 years ago, the Hoeckelingsdam was constructed in the IJmeer as a compensation measure for the construction of IJburg. This breakwater, together with Polder IJdoorn and the Uitdammerdijk, encloses the Kinselbaai. Due to subsidence, current, and wave action, part of the dam sank underwater. Restoration was necessary for the preservation of the Hoeckelingsdam. This restoration work started in the second half of 2024.
The Hoeckelingsdam has been reinforced and raised with sand and riprap that became available during the reinforcement of the Markermeer dikes. For this, Rijkswaterstaat collaborated with the Hoogheemraadschap Hollands Noorderkwartier and the Markermeer Dikes Alliance. The Delta Fund for Freshwater also contributed to improving breeding and foraging areas for migratory birds.
Earlier in 2025, the temporary connection with the dike, for the execution of the works, was removed. Hoeckelingsdam was once again an island before the breeding season.
Building with Nature
By building according to the principles of Building with Nature, sand from the surrounding area has been smartly reused. This is not only sustainable and cheaper, but it also limits the number of transport movements. The sand has been placed in one large pile behind the stone dike and will spread over the Kinselbaai in the coming years due to water movements. This has the advantage of preserving as many aquatic plants as possible.
At the same time, this creates a larger habitat for birds such as the common tern and the black tern. For birds, part of the sand dam has also been finished with gravel and shells. To ensure enough shelter in the Kinselbaai, a brushwood dam has been constructed on the southern side. This dam ensures that the sand remains within the Kinselbaai and does not end up in the IJmeer.
Ecologist John van den Belt: The breeding season is still in full swing. After the breeding season, we can monitor whether the dam has been used a lot by, for example, counting old nests. However, we have already been able to see from the dike that there is a lot of interest from birds in the Hoeckelingsdam. This is also the expectation in a pioneer situation: there is a lot of space with little vegetation where pioneer species such as the little ringed plover, gull species, and common terns will come.
Double Win for Nature and Environment
By restoring the Hoeckelingsdam as a nature island, a beautiful example has emerged of how humans and nature can work hand in hand towards a sustainable future.
The restoration not only contributes to the goals for the ecological status of water quality (Water Framework Directive), but also to the established conservation goals of Natura 2000.