This paper reports on an extended-period simulation for predictions of the flows and pressures of a municipal water supply system. The program has been developed within the scope of the Real-Time Intelligent Systems Project at the University of Regina, Saskatchewan, Canada. The aim of this project is to develop a real-time decision support system for monitoring and control of the water pipeline network operations. The system supports the operator＇s decision-making in maintaining the distribution pressures of water at the pumping stations at all times. The system consists of three modules : an expert system module, a water demand predictions module, and a pipeline network simulation module. In this paper, we describe the simulation module which has been implemented using the Hardy-Cross and Newton-Raphson methods. The programs were implemented in MathCad and FORTRAN. A comparison of the two implementations is presented, and some results from the simulations are described.