Freshwater plumes in continental and shelf seas are common, relevant features of the coastal environment and its management. In order to analyze and predict the overall shape and scale of freshwater plumes, the well-known hydrodynamic model COHERENS was used to perform several simulations of river-plume evolution. The area considered in this study has an idealized straight coastline with longitudinally uniform bathymetry and a constant bottom slope. In this domain, constant river discharge is assumed with an outflow rate ranging from that of typical mean conditions for small-scale Mediterranean rivers (e.g., Júcar) to that of larger-scale ones (e.g., Ebro). A simplified version of the underlying mesoscale circulation is considered and the effects of wind-forcing on the evolution of the freshwater plume are taken into account by considering different wind scenarios. This study describes the physical characteristics and associated dynamics of a river plume as a function of the river-flow magnitude for a Mediterranean-type receiving water body. The results of numerical simulations allow us to assess the relative importance of different factors (e.g., river-flow rate, wind parameters, etc.) on the overall dynamics and physical characteristics of the freshwater plume (including both alongshore and across-shore length scales).