A sine qua non of control system development for modern sewer networks is the preservation of the water system around a network's outflow(s). Several approaches have been proposed for the optimisation of sewage control and Optimal Real-time Control of Sewer Networks provides a comparative synthesis of a central sewer network flow control based on two of these: nonlinear- optimal and multivariable-feedback control. Testing and comparison of these protocols are made on the basis of their control results for the large-scale sewer network located around the river Obere Iller in Bavaria. The control strategies implemented within this network are based on this study. From the selection of