Vulnerability of Urban Water Distribution Networks under Intermittent Water Supply Operations

The work presented herein investigates the effects of intermittent water supply (IWS) on the condition and breakage rate of urban water distribution piping networks (WDN), by studying the change in the rate of occurrence of failures before, during and after IWS periods, using statistical and survival analyses. The analyses, based on a seven-year dataset (2003–2010) from a major urban center of about 300,000 residents, take into account information related with breakage incidents and with operating system parameters, as well as external factors and vulnerability assessments of the network’s key components. The results show an increase in the number of waterloss incidents during and immediately after the periods during which IWS practices were implemented, and they reinforce the belief that IWS practices negatively affect the vulnerability of WDNs.