Water distribution system reliability under simultaneous multicomponent failure scenario

Water distribution systems (WDSs) face numerous challenges in providing service to their customers. An especially difficult challenge occurs when several pipes in the system fail simultaneously. Simultaneous failure is more likely to occur in older networks or systems located in harsh climatic conditions. Previous studies have focused on WDS reliability when pipes fail individually. The current research proposes a technique to determine the reliability of a WDS experiencing different degrees of simultaneous pipe failure and to assess errors in reliability that occur when an inappropriate level of simultaneous failure is assumed. The model was applied to two case studies including a hypothetical small system and an actual WDS. Comparing the various states of reliability provided valuable information about system sensitivity to simultaneous multipipe failures. Results demonstrated that a system may be able to achieve a higher level of reliability if more realistic expectations of simultaneous failure are assumed.