On 2 December 1959, the breach of the Malpasset arch-dam in Fréjus (Var, French Riviera) caused the sudden release of 48 million m3 of water what flooded and devastated the Reyran valley and the coastal low-lying plain of the Argens River. The small town of Fréjus was submerged by a 2 meters high wave of water and mud. There were 423 victims. The dam flood moved large amount of sediment in the rivers channels and on the ground in the valley and in the plain as well as on the shoreface and the continental shelf. In some places, the soil has been stripped; in other places, accumulation of several tens of centimeters thick was measured. A diachronic analysis of vertical aerial photographs from 1944 to 2015 in a Geographic Information System highlights the short-term impact of the disaster on the shoreline: it was before stable in the medium term, and then experienced an accretion phase from 1959 to 1962 which can be put into relation with sediment deposition on the shoreface du to the flooding. It finally returned to its former position.