The urbanised area located at the outlet of the Cannes watershed suffers frequent flooding during significant rain events. In the area of Alzo di Leva, three retention works are envisaged: Alzo di Leva I (1.6 ha), Alzo di Leva II (0.6 ha) (established in 2012) and Alzo di Leva III (1.35 ha).These retention works are intended to regulate flows on the Cannes Creek, which crosses the lower part of the City of Ajaccio before being discharged downstream of the Prince Imperial Course. As part of the transfer of competence to Capa, the Agglomeration Community of the Ajaccien country plans to build the Alzo di Leva 1 basin (9 500 m³) which will guarantee protection for a 25-year return period in the current state of waterproofing. A channel of transfer of the flows of dry weather and rain time to channel the flows through the basin will be set up. This development as a whole must make forget the technical aspect of the basin in particular by the shaping of the topography and the various and adapted plantations. The wetland character of the area must be kept to the maximum (planting of hygrophile plants, favourable to the fauna present in environmental wetlands, etc.) The project will integrate the construction of upstream and downstream connection works to the existing networks, in particular those created as part of the PRU Cannes and Rocade projects in Ajaccio.