Modeling and Performance Evaluation of Intermittent Water Supply Systems

Abstract

Water supply systems are made up of various components that work together to collect, store, treat, transport, pump, and distribute water. In this context, pumping and distribution are particularly important for our discussion. Pumping involves the pumps and their supporting equipment, while distribution encompasses reservoirs, pipes, valves, and fire hydrants. Pumping stations are essential to water distribution networks (WDNs), and a significant portion of the operational costs in these networks comes from the energy used by pumps. The specific goals and limitations of each scheduling issue can differ significantly from one situation to another. For instance, when it comes to scheduling, some common objectives might include fairly distributing the available water, cutting down on operational costs, or maximizing social benefits. In areas where water is scarce, ensuring an equitable distribution often takes precedence. On the other hand, energy optimization becomes a key focus in systems that have enough water supply. The constraints involved in these problems generally fall into three main categories. The first category deals with the hydraulic model. The second includes physical limitations, such as the capacities of pumps and reservoirs, as well as the availability of water and workforce. Lastly, the third category encompasses the modelling constraints necessary to translate the scheduling problem into a mathematical framework. Notably, in systems with ample downstream storage, the constraints related to reservoir capacity tend to be less of an issue. However, for systems that rely on manual operation, the availability of manpower can be a significant constraint.