Hydraulic Simulation of the River Zenne and the Sewer Collectors in the Brussels Region

Abstract

In "Hydraulic Simulation of the River Zenne and the Sewer Collectors in the Brussels Region" a hydraulic model has been built and run for the River Zenne and the Sewer collectors which are connected to the Waste Water Treatment Plant Brussels North. This model has been built in EPA SWMM, this is a dynamic rainfall-runoff simulation model used for single event to long term (continuous) simulation using the Saint-Venant flow equations.
The data used in previous studies concerning the behaviour of the sewer network has been re-used in this model. The new left bank collectors as well as the Waste Water Treatment Plant Brussels North have been added to the model.
Several short term simulations have been run in order to initialise and calibrate the model. Those simulations have lasted 12 hours and were run with design storms with a return period of respectively 2 and 10 years.
Finally, a simulation has been run with measured rainfall for 2007. The modelled flows in different locations of the system have been compared with measured flows. Special care was taken with regard with water that enters the Zenne or the Canal without being treated. These overflow volumes are a critical issue in the model as they are very sensitive. We want to predict, in function of the rainfall, whether water leaves the sewers without being treated or not.
The model seems to give reliable results for the flows throughout the system as well as for the overflow discharges. Nevertheless, the used rainfall data as well as the flow measurements throughout the sewer system seem to contain major errors or contain no measured values for certain periods. Those lacks affect the validation of the model.
After improvement, this model will be implemented in a larger model performed by the Department of Hydrology and hydraulic engineering of the VUB.

Date of Award	2010
Original language	English