Abstract. This paper presents an appraisal of the temporal evolution of flood vulnerability of two French cities, Besançon and Moissac, which were largely impacted by floods in January 1910 and March 1930, respectively. Both flood events figure among the most significant events recorded in France during the 20th century, in terms of certain parameters such as the intensity and severity of the flood and spatial extension of the damage. An analysis of historical sources allows the mapping of land use and occupation within the areas affected by the two floods, both in past and present contexts, providing an insight of the complexity of flood risk evolution at a local scale.

Abstract. This paper presents a diachronic appraisal of flood vulnerability of two French cities, respectively Besançon and Moissac, which have been largely impacted by two ancient floods in January 1910 and March 1930. Both flood events figured among the most significant events recorded in France during the XXth century. An analysis of historical sources allows the mapping of land use and occupation within the flood extent of the two historical floods, both in past and present contexts. It gives an insight of the complexity of flood risk evolution, at a local scale.