Grebbedijk area development

The centuries-old Grebbedijk between Wageningen and Rhenen no longer meets current safety standards and is being reinforced under the Flood Protection Programme (HWBP). Although the dyke is relatively short at 5.5 kilometres, it plays a vital role in maintaining flood protection. On behalf of the Boskalis & Wetering consortium, Koningswaard, Iv is developing the integrated design for this extensive project, combining flood protection with sustainable area development.

The dyke reinforcement is located in a constrained area, close to listed buildings and other development. This calls for carefully considered technical solutions, such as the precise design and installation of steel sheet piles and the integration of raised ground levels and new structures without placing undue strain on the surrounding area. In the open landscape, the stability berm must also be carefully integrated into the wider spatial ambitions.

The design team is also assessing sustainable measures to prevent piping, including heave screens, vertical sand-tight geotextiles, a coarse-sand barrier and a polymer filter screen. Ecology, nature and cultural heritage are considered throughout the design process. This is reflected in the construction of a Water Framework Directive channel, which will improve habitats for plants and wildlife, and in the careful removal of the old Witte Sluis, a historic hydraulic engineering structure.

Iv is contributing to a future-proof dyke. Smart innovations help limit the required crest height, reducing construction volumes and environmental impact, while soil, sheet piles and grass revetment are reused. Piling trials minimise noise and vibration for local residents. The result will be a safe, sustainable and climate-resilient dyke that also enhances nature, recreation and spatial quality.