On-Line Hydraulic Modeling of a Water Distribution System in Singapore

Abstract

This paper presents an on-line hydraulic model of an urban water distribution system in Singapore. The proposed method starts with identifying demand zones (i.e., clusters of water consumers) within the complex topology of the urban water supply system. The demand zone identification method implements optimization tools and graph algorithms to partition the system into homogenous clusters. Thereafter, an on-line Predictor-Corrector (PC) procedure is employed for forecasting future water demands of each zone. A statistical data-driven algorithm is applied to estimate future hydraulic states and an evolutionary optimization technique is used to correct these predictions with near real-time monitoring data provided by the WaterWiSe@SG (Water Wireless Sentinel at Singapore) wireless sensor network. The calibration problem is solved using a modified Least Squares (LS) fit method in which the objective function is the minimization of the residuals between predicted and measured pressure and flow rates at several system locations, with the decision variables being the hourly variations in the zones/ clusters water demands.