Supervision du réseau d’assainissement de Marseille et gestion des épisodes pluvieux

Supervision of the Marseilles sewerage system and management of rain occurrences

¹ SERAM 24 a, rue Fort Notre Dame, 13007 Marseille
² CUMPM DEA 27, Bd Joseph Vernet, 13008 Marseille

Auteur de correspondance : dominique.laplace@seram-marseille.fr

Abstract

Faced to the rainfall risks, the City of Marseilles proceeds with the forecasting and the real-time management of the sewer network and of field action plans. The main purpose is to anticipate and to activate before the rain starts an operational plan of information and of ground actions and then to manage it during the rain. Depending on the rain severity, the management gives priority to different fields : In the event of light rainfall – in order to preserve the quality of sea-water for bathing, thus avoiding sewer discharges.In the event of average rainfall – in order to avoid surface flooding in the city, thus giving priority to sewer overflows towards the sea.In the event of heavy rainfall – in order to ensure public safety, thus managing assistance plan by the municipality services.Therefore, relationship between rainfall and severity levels were established for the city, considering the data on rainfall and its potential effects on the sewerage system, flooding points and also the number of field interventions due to phone calls. Finally, risk management is based on a simple decision-making model, using as input, predicted data, measured rainfall and real water level measurements. Non-dangerous rainfalls are managed by the sewerage system exploitant and dangerous rainfalls by local authorities.