Real-time control can be used to prevent combined sewer overflows, by maximizing the amount of water stored and minimizing the amount of water discharged to the natural environment. Existing methods use optimization as a control means, which may be too costly for small cities. We propose in this article a method to control urban water network using simple controllers. A model of a pilot site (Biarritz) has been built with the software SWMM5 (sewerage modeling software) which is linked to Scilab, to test various control strategies. We first consider two classical control policies for the sewerage system: the local upstream control and the distant downstream which have their advantages and drawbacks. In this study, we propose the mixed control which ensures the benefits of these two types of control.