Samenvatting

The Eastern Scheldt faces sand starvation as a result of the Eastern Scheldt storm surge barrier construction, which has led to a decreased tidal prism and subsequent loss of intertidal areas. These areas are crucial for birds and seals to rest and forage for food. To address this issue, Rijkswaterstaat implements a rotational nourishment scheme for the intertidal flats. For instance, in 2019, 1.3 million m³ of sand was nourished at Roggenplaat, and in 2026, the
Galgeplaat and Slikken van den Dortsman are scheduled for nourishment, to mitigate the effects of the sand starvation and loss of intertidal habitats. Even though this approach has proven effective, regular dredging activities in navigational channels and harbours provide an additional source of sediment. In the current practice, this sediment is typically dumped in deep pits. This research paper explores alternative applications for sediment from regular
dredging activities, with a primary focus on nature restoration and water safety. First, an inventory of the sediment volumes and locations was made. Then, the suitability for a number of innovative applications of dredged sediment (including sand motor, mud motor, direct nourishment of salt marshes and meegroeidijk) was evaluated based on hydrodynamic, water safety and ecological criteria. Twenty-three suitable locations were found, which were
examined using a Multi-Criteria-Analysis. For the three winning solutions a detailed calculation was made on how many sediments are needed to implement them, as well as drawings of the projects. The three winning solutions are a mud motor, a direct nourishment of salt marshes at the Slikken van den Dortsman area and a sand engine at Speelmansplaten.
Experts from various backgrounds were consulted to reflect on the chosen solutions and the feasibility of the chosen nourishment methods. Lastly, recommendations on the best ways to use the sediments that are accessible will be given.