This work presents the results of an experimental program carried out in a physical model of an ocean outfall. The initial aim of this campaign, promoted and funded by the Regional Hydraulic Authority of Galicia, is to analyze the efficiency of various submarine outfalls currently operating in the estuaries of Galicia (Spain), and to propose design improvements for future discharge infrastructures. Concentrations were measured with Laser Induced Fluorescence technology (LIF) for 84 different discharge configurations, representing both real operation conditions and variations of main design parameters.