Floodplains are known to be areas of extraordinary biodiversity with a mosaic of shifting habitats with high interdependency. Such complex ecosystems fulfil a wide range of ecosystem services concerning economic, social and ecological functions. Moreover, functioning as complex ecotones at various spatio-temporal scales, floodplains usually provide a diversity of habitats and microhabitats for many organisms from river channels to uplands. However, these ecosystems have been largely subjected to human pressure through the embanking of rivers. Such damages have led to river restoration projects in order to re-establish a near-natural alluvial dynamics and to recover floodplain naturalness and biodiversity. In Switzerland, several projects have been implemented to maintain or recreate floodplain ecological functions, in particular for flood protection and biodiversity. In such context, this chapter highlights biological and pedological features as indicator tools to evaluate the success of floodplain restoration, focusing on earthworm communities that are assumed to vary in terms of species diversity, abundance and biomass along a gradient of naturalness from the embanked system to the near-natural reference. The first section of the chapter deals with floodplain restoration and potential consequences on soil functions. Then, the second section presents an overview of earthworm communities and activities as ecosystem engineers, their habitats and their potential resilience to disturbance and stress. Concerning near-natural floodplains in Switzerland, the third section focuses on earthworm communities and environmental variables that may affect their distribution taking into account two spatial variables: 1) an altitudinal gradient from subalpine to hill levels, and, 2) a gradient perpendicular to the river, stratified by vegetation. The impact of fluvial dynamics is also discussed. The fourth section addresses the comparison of two floodplains that are partly embanked and restored (The Emme and Thur Rivers) and highlights the potential of earthworms as bioindicators of early stages of river restoration. Finally, the last section proposes future prospects to assess the success of ecological restoration, i.e. the self-sustainability of restored floodplains.