This work reports the results obtained in the third phase of the OPUR program on the quality of wastewater passing through the Parisian sewer network, and in influent and effluent of the wastewater treatment plant of Seine Centre. Its purpose is to establish an inventory of the contamination by phthalates in an urban area. Furthermore, this study aims to determine the efficiency of various treatment processes (physico-chemical lamella clarification and biofiltration) in the phthalates removal. Concentrations in sewer network fluctuate between 0.60 and 3.91 μg/L for DnBP and BBP, and between 5.23 and 161 μg/L for DEP and DEHP. Additionally, concentrations vary between 0.97 and 6.01 μg/L for DnBP and BBP, and between 7.00 and 71.88 μg/L for DEP and DEHP in the raw influent. For DEHP, the concentration in the treated water (2.30 μg/L) exceeds the current EQS (1.30 μg/L) defined for the receiving environment. However, a dilution effect of these waters in the receiving environment will reduce the impact of this compound for the local flora and fauna. Finally, significant proportion pollution (> 83% for all compounds) is eliminated in the physico-chemical lamella clarification and the biofiltration with a lamella clarification that will promote the elimination of heavy compounds (DEHP, DBP and BBP) and a biofiltration eliminating mainly light compounds such as DEP.