Amélioration potentielle de la gestion des effluents de temps de pluie grâce à des mesures de turbidité

Turbidity sensors can be used to continuously monitor in real time pollutants loads, especially during wet weather. Continuous turbidity, conductivity and flow data were recorded at one-minute time intervals over a one-year period for two sites within the Paris combined sewer system. This paper highlights the intra- and inter-event variability of turbidity responses depending on the rainfall event. For each rainfall event, turbidity response aspects were analysed through different classifications (M(V) curves and main dynamics features) and according to different parameters such as the antecedent dry weather period, the total event volume per impervious hectare and both the mean and maximum hydraulic flow. Results show that turbidity contains important information for wet weather management, which are not included in hydraulic flow dynamics and not linked to the studied parameters. Knowledge of turbidity dynamics could therefore potentially improve wet weather management, especially when using pollution-based real-time control.