In the present work, the importance of watershed sediment modeling to coastal morphology is studied for a torrent watershed in Chalkidiki, North Greece. The impact of the land use changes that took place within the watershed on the overland and channel sediment transport, was simulated applying the SWAT model in GIS environment. SWAT was initially calibrated based on the results of the shoreline evolution model PELNCON-M developed by the authors, which confirmed the measured shoreline retreat in the vicinity of the torrent’s mouth. Comparative analysis of the models’ output for the inland and coastal fields, denoted the significant correlation of the above phenomena and indicated the parameters that need to be further investigated in order to improve the reliability of the proposed methodological approach.