TKI - report Meegroeidijk Lauwersoog

This report presents the outcomes of the TKI project – Meegroeidijk Lauwersoog, focusing on the development and testing of the Growing Dike Concept (GDC). This report describes the outcomes of the TKI project – Meegroeidijk Lauwersoog. The GDC, using thin layers of dredged material to reinforce dikes, had before this TKI project only been developed on paper, starting in 2019. This was done partly through a conceptual feasibility study, but never tested on small-scale experiments or in a field setting. Within this TKI project the first implementation of the GDC was tested and analysed in small-scale experiments at Deltares (Delft) and in a field pilot at the dike east of Lauwersoog. The TKI project is an innovative collaborative project together with partners from the waterboard Noorderzijlvest, Wageningen Marine Research, HAN University of Applied Science, Klaei BV, Havenbedrijf Lauwersoog and Deltares (project activities coordinator). The GDC involves the reinforcement of flood defences by periodically adding locally dredged material, aligning with the principles of ‘Slow Building’, ‘Building with Nature’ and ‘Beneficial Use of Sediment’. This approach has the potential to enhance long-term flood defence reinforcements by repurposing locally dredged sediment as a valuable building material instead of being removed from the system as undesirable material. In addition, this approach has potentially an impact on reducing Green House Gas (GHG) emissions compared to conventional reinforcements. The GDC offers a promising integrated solution to major challenges like sea level rise and subsidence, improving water safety in coastal and river areas. In addition, the local re-use of raw material, such as sediment from ports and waterways dredging, could potentially reduce the GHG impact of dike construction and maintenance. The gradual application of sediment may expand the lifespan of flood defences, delaying or even preventing costly maintenance while mitigating flood risks. In addition, the direct use of local sediment eliminates the need for maturation in specific depots, streamlining the connection between dredging and dike maintenance.