Valve management robust optimization to enchance water quality in WDN under uncertainty

“Water distribution networks are designed to deliver water complying with standards of pressure and quality. Water quality deterioration can be caused by high water residence time (water age) in the network. For this reason, the water age is often assumed as a valuable surrogate of water quality in Water Distribution Networks (WDN) (Shokooni et al. 2017) and a good management should keep low values in the system.
The main factors contributing to increased water age are the design of WDNs to cope with future demand based on an estimated growth of the population, possible commercial and industrial developments, and fire protection, which leads to the oversized capacity of the system. The reduction of water age can be achieved by an appropriate valve management, which can be expressed as an optimization problem. Prasad and Walters (2006) suggested to minimize water age by finding optimal operational valves status using a single-objective optimisation problem formulation solved with genetic algorithms. More recently, Quintiliani et al. (2019) addressed the same problem with a multi- objective optimisation formulation, in which both the water age and the number of operational interventions are minimised.”

(Citaat: Marquez-Calvo, O., Quintiliani, C., Alfonso, L., et al. – Valve management robust optimization to enchance water quality in WDN under uncertainty – L’Acqua (2019)Sept. – Oct., p.101)