Failure Impact Analysis of Isolation Valves in a Water Distribution Network

Isolation valves are crucial components of water distribution systems for separating pipe segments from the network for repair or maintenance purpose. This paper looks at the impacts of isolation valve failure on three indictors, including number of valves needed to isolate a distribution system segment, size of distribution system segments, and shortfall in meeting demands during failure. A network with various isolation valve configurations in terms of valve density is used as a case study. The results obtained from the case study show that the failure of an isolation valve has substantially varying impacts on system performance during a shutdown. The valve density in the network determines the impacts of inoperable valves on a shutdown. Generally speaking, a higher density of isolation valves leads to the less impact of valve failure. Finally, several conclusions drawn from the critical valve analysis in this study can be applied to guide isolation valve maintenance and management. (C) 2017 American Society of Civil Engineers.