We propose to test the depollution efficiency of a storm basin. The study involves setting up different types of obstacles and different layout configurations in the basin and determining the amount of sediment deposited under different hydraulic conditions. The experiments are carried out in a rectangular basin of 1800 mm long × 760 m width. The sediments used are white polystyrol particles of diameter varying from 0.350 to 1.40 mm. Its density is 1.03 g/cm3. Twenty experiments are carried out to determine the efficiency of sediment deposition. We used various arrangements of obstacles placed inside the basin. The experiments were performed using five flow rates varying between 1 L/s and 5 L/s for each arrangement. The results obtained show that the arrangement of the obstacles in the basin and the flow rate have an effective influence on the hydraulic behavior of the sediment deposition and the depollution efficiency. In the case of the basin without obstacles, the deposition efficiency decreases as the flow rate increases. The basin is relatively efficient at low flows (96.1% for 1 L/s), but its performance quickly becomes limited at high flows (14.5% for 5 L/s). The presence of columns inside the basin slightly increases the deposition efficiency (approximately + 10%) for each flow rate. In the case of a rectangular plate disposed in front of the flow inside the basin, the deposition efficiency is greater than 94% whatever the flow.