The global coastal landscapes are undergoing constant transformation through the construction of infrastructure (digues, jetties) that meet the growing demands for economic activities. The coastal natural environment is fragmented by human construction encroaching on the ecological habitats of intertidal areas. This character is particularly marked on the coasts of the Channel for which the marnage is high. Until recently, the response to a marine submersion event was approached from a pure engineering perspective with the construction of a new infrastructure in response. Over the past decade, a paradigm shift has emerged by integrating nature and society into the technical approach of coastal projects. In the Netherlands, the Building with Nature concept emerges through a very large, life-sized experience (Sand Motor) to protect a coastal line using high-volume sandy recharge and to provide a soft and long-term response to the problem of coastal erosion. In Northern Europe, for example, buffer zone strategies allow for the gradual construction of sedimentary and wetlands, ecosystem-friendly and protective until the next centennial storm. The variables and conditions of the environmental system are integrated from the outset of the project, taking into account long-term changes at the limit of the engineering time scale. Here, ecosystem services are already of great magnitude through the attenuation function of marine submersion, the creation of recreational and recreational areas, the formation of a rich ecosystem on the shoreline, and the preservation of freshwater groundwater. The main objective of this project is to create and study two pilot sites in the Normandy region by integrating two types of artificial blocks with existing dikes (Cherbourg, Ouistreham) through approaches to social acceptability, biodiversity and coastal engineering. This multidisciplinary project involves a regional maritime works company (MARC SA), a study and research office (ARTELIA), an engineering school (ESITC Caen), three research laboratories at the University of Caen (CERREV, BOREA, M2C) and Ports de Normandie.Severe hydrodynamic conditions involve the use of concrete block (BCR, ACCROPODETM) in place of natural rock rocks in order to ensure greater stability of the defence structure and also to limit crossings. A block of carapace (Double-Cube) was developed in the M2C laboratory. This block has many assets (performance, ease of installation, multi-purposes), however it has not yet reached the stage of an industrial demonstrator. Similarly, ARTELIA has designed a new generation of foot blocks for slope dikes: the AccroBermII (ABII). The ABII foot block replaces the foot stop (stabilisation of the carapace) thanks to its circular shape. Due to its hollow shape, its stability is also ensured by infilling using riprap. Several environmental benefits emerge (limited influence on the seabed, limited indirect environmental impacts, interactions with biodiversity). A comparative study of the biodiversity of a coastal line protected by artificial or natural rocks will be carried out through ecosystem approaches on macroflora, macrofauna and microalgae biofilms. CERREV will question the responses of the populations in the Region to a potential installation of these blocks. The presentation of the consequences of flood risks may not necessarily lead to awareness or acceptance of potential remediation. CERREV will analyse these reactions in order to facilitate the choice of possible options.