From pilots to policy: upscaling sediment management strategies for climate resilience in a transboundary estuary

The Ems Estuary faces existential challenges including flood risk, increasing turbidity, and biodiversity loss, all of which may intensify under future climate scenarios and require transboundary collaboration between the Netherlands and Germany. Addressing these challenges requires compliance with EU, national, and local regulations. Simultaneously each nation pursues socioeconomic benefits from the restoration through a holistic, system-based approach. This study synthesizes the key processes driving flood risk, hyper-turbidity, and salinization within the Ems Estuary. From this understanding the paper catalogues the planned and implemented pilot measures from both countries to advance their climate adaptation plans. Both nations share a common vision of leveraging the high turbidity of the estuary as an asset in climate adaption, e.g. for land raising, dyke reinforcement or habitat creation. Building on the pilot projects and shared visions, three transboundary upscaling strategies involving sediment management are proposed: (A) land elevation using dredged sediment; (B) multifunctional flood defences incorporating nature-based solutions; and (C) habitat creation and restoration to enhance ecological resilience. The Ems Estuary offers valuable insights for global transboundary estuarine management, illustrating how innovative sediment management and transboundary cooperation can be achieved to support climate adaptation and sustainable development. The study underscores the need for harmonized governance, standardized success metrics, and cross-border planning to enable effective upscaling.