This work designs a low-cost and reliable system for monitoring water quality and accurate detecting contamination levels in real-time. The system notifies the consumers about the status of their households' supplied water. The system involves a multi-sensor array placed at the water supply pipe that measures five physicochemical parameters commonly used as indicators of water quality. These parameters are pH, temperature, turbidity, oxidation-reduction potential, and electrical conductivity. Water contamination is detected using a sensor fusion approach; two intelligent algorithms are developed to fuse the multi-sensor array readings and detect contamination. The proposed system is simulated using the LabVIEW environment. The simulation is performed to evaluate the system's performance in the events of contamination at any concentration level. The obtained results demonstrate the warning system suitability for accurate online detection of contamination.