Optimization of Leakage in Water Distribution Networks Using Pressure Reducing Valve

Excessive water loss from drinking water distribution network is a serious problem in many countries all over the world including Turkey where total water losses is around 45% of the distributed water. Water loss not only cause a critical amount of energy and economic losses but also results in water quality and sustainability problems. Thus it is crucial to determine, reduce and manage water loss. The most effective means of reducing water loss in distribution systems is proven by former studies to be the control of excessive pressures in the network. In this study, an optimization method is developed to minimize leakage in a water distribution system by pressure reducing valves (PRV) usage. The aim is to optimize tolerance, which is the difference between existing and predefined minimum allowable nodal head, while considering pressure head limitations and PRV settings. The leakage is expressed as a function of pressure, due to the strong correlation between them. In addition to that, chance constraint is applied to cover uncertainties in the system which are resulting from the change of roughness height of pipes with time. Network hydraulics and optimization model are solved by simultaneously using EPANET and GAMS, respectively