Abstract: Reservoirs are important for providing water for different uses, enabling flood mitigation and sometimes hydropower generation, especially in the context of responses to global climate change. Despite their strategic importance, the presence of a reservoir can induce impacts on the sediment transport in rivers with effects on river morphology with erosion downstream of the dam and sedimentation in the reservoir. Disueri reservoir, in Sicily, Italy, was selected as a case study because, in the face of strong sedimentation in the reservoir, coastal erosion phenomena are evident along the downstream coastal zone. To calculate water and deposited sediment volumes present in the reservoir, a 3-D topographic model was created combining the different topo-bathymetric surveys and comparing them with the historical data. The model was also used to calculate the annual sediment yield (SY) of the reservoir. To define possible sediment management solutions, chemical analyses were performed on the deposited material. The high annual SY (range 356,000-505,000 m3 year-1) recorded in the Disueri reservoir places a high risk for the water requirements of the territory and for agricultural production. The Disueri reservoir contains 9.7 M m3 of deposited sediment in a potential water storage capacity of 23.6 M m3; in addition, the low water level to be maintained inside the reservoir (for security reasons) has made the reservoir virtually waterless. The large quantity of sediments annually eroded by the upward basin (239 km2) are intercepted by the dam and the interruption of the sediment transport causes risks for the downstream river morphology and for erosion along the coast. The high SY makes it difficult not only recovering but also maintaining the active water volume over time. The proposed solution, with a view to safeguard the reservoir in an upstream‒downstream context, is framed as an integrated approach combining different actions (engineering intervention on the dam, dredging, vegetation management with biomass energy production and sediment bypass tunnel) and make it possible to bring the reservoir back into ordinary operation and facilitate the transport of sediments to the coast, thus reducing coastal erosion. For the maintenance of the active volume and to counteract the silting in the reservoir, it will also be necessary to implement forms of diversion of the incoming sediment, thereby restoring the sedimentary balance of the river‒coast‒sea system currently interrupted by the presence of the dam. To do this, the implementation of a Sediment Bypass Tunnel was studied.