The impact of various water management alternatives, resulting from the construction of the La Vinuela reservoir system (Málaga, Spain), on the hydrological regime of the coastal aquifer of the Vélez River has been analysed. In particular, steady-state simulations of the freshwater regime have been carried out under various possible management policies for this reservoir system. For this purpose, a finite element model was used, which was designed to take into account the relationship between the groundwater and surface water, the different hypotheses for the mixture of freshwater and saltwater, and the special treatment of the open boundaries of the aquifer at the coastline. The simulations consider average freshwater inputs as well as different water management and exploitation alternatives for surplus and deficit of freshwater. The accomplished simulations provide the phreatic levels, the active drainage network and the thicknesses of freshwater and saltwater as a result of the advance of the saltwater interface. The results of the simulations appear to be reliable according to the existing experimental data on the region. The simulation alternatives illustrate the main limitations of the aquifer for storing and transmitting freshwater, and preventing the advance of saltwater intrusion resulting from the exploitation by pumping in wells and water management policies in the La Vinuela reservoir system.