The worldwide extent of tidal wetlands has greatly decreased, primarily due to large-scale embankments for agricultural, industrial and urban developments. Such pressures have resulted in narrowing estuarine corridors and in increasing shear stress on the remaining estuarine habitats. Concomitantly, the increased mean high water level has constrained ecological restoration in adjacent embanked areas. The inability to create an adequate tidal regime in embanked areas is a major problem for restoring estuarine habitats. A new restoration technique, the controlled reduced tide system (CRT), was hypothesized to overcome this constraint. As part of a management plan combining flood protection and tidal habitat restoration, the first CRT system was implemented in polder from the freshwater zone of the Schelde estuary (Belgium). In an interdisciplinary context, this work focuses on different ecosystem compartments and interactions in order to assess the coherence between abiotic and biotic components and to appraise the relevance of further wide applications in tidal wetland restoration. Within four years following the connection of the polder to the estuary, different ecosystem compartments and processes were studied: hydrology, sediment physicochemical characteristics, and invertebrate and bird communities. Despite some slight deviances from the reference, the tidal characteristics generated by the CRT technique were suitable with a clear reproduction of the spring-neap tidal cycle. This soft hydrology led to the formation of a finegrained estuarine sedimentary substrate in the most frequently flooded zones, contrasting with estuarine sand flats. Biogeochemical services such as sediment trapping and nutrient burial were demonstrated. These new environmental conditions were shown to be more suitable to sediment invertebrate community development than those encountered in reference sites from the adjacent estuary. CRT habitats displayed enriched communities, especially with epibenthic organisms. Divergence in community ...