Hydrocarbures aliphatiques et aromatiques introduits dans le réseau d'assainissement via les effluents domestiques

Since 1994, several studies were carried out within the framework of the OPUR (Observatory of Urban Pollutants) research program in order to improve the knowledge on the introduction and transfer of hydrocarbons into combined sewers. This paper aims at investigating the aliphatic (AH) and polycyclic aromatic hydrocarbon (PAH) loads introduced into combined sewers by three types of domestic effluents : i) purely domestic effluents, ii) domestic effluents mixed with effluents from catering activity and iii) domestic effluents mixed with effluents from garage activity. Results show hydrocarbon concentrations of domestic effluents in the 200 - 300 μg.l^-1 and 0.9 - 1.4 μg.l^-1 ranges for AHs and the PAHs, respectively. The daily hydrocarbon fluxes conveyed by domestic effluents are evaluated on the scale of the "Le Marais" experimental urban catchment [42 ha, centre of Paris, about 13 000 inhabitants] between 600 and 1600 g for AHs and between 2.1 and 4.5 g for PAHs. Finally, the qualitative approach reveals that dry weather flow [DWF] presents close aliphatic and aromatic fingerprints to those observed for strictly domestic inputs.