Long term pollution simulation in combined sewer networks

This paper presents results of long term pollution simulations on the examp le of the sewerage system of Grand-Couronne. This modelling work is part of a study where objective is to develop a method to define the reference flo w of a WWTP. The model HYDROWORKS DM (TM) has been successfully validated i n hydraulics and pollution for the sewer network, for long time simulations . A conceptual model has been built to model the pollution in the tank at t he outlet of the combined system. One synthetic year of rain has been used to simulate the working of the "up stream system" of the WWTP (combined sew er + tank + separate sewer + pre-treatments) and has been successfully vali dated by measurements of the 1998-1999 year. If this paper is focused on th e "up stream system", the SIMBA/SIMBAD WWTP model has been successfully cal ibrated and validated too, and the combination represents a fully validated "Integrated Model" for the sewerage system.