Sensitivity Analysis of Water Distribution Networks Deterioration in Hydraulic and Economic Parameters

Abstract

Water Distribution Networks (WDNs) are responsible for the majority of the costs in a water supply system. Thus, it is reasonable to carefully evaluate the possible interventions to achieve the one with the best cost benefit. Usually, WDN’s projects are designed for a life cycle of 20 years, but many systems are already operating longer than this, up to 100 years. Obviously, several maintenance services are necessary during this period, but the knowledge of how the system deteriorate can help the management of these services and keep the operational efficiency high, Therefore, in this work the deterioration of the components of a WDN is evaluated trough the economic losses generated and the pressure deficit. The pipe deterioration is modelled considering the roughness increases at a certain rate. Pumps deterioration are similarly modelled, considering the formation of internal roughness that increases the internal recirculation. Finally, the demand increase is also modelled considering the population growth rate and a minimum leakage flow rate. In addition, pressure dependent leakages are modelled as an orifice, maintaining its characteristics constant during the simulation. The results shown that maintenance services are essential for the efficient operation of WDNs, with leakages representing the most impactful problem.