Impacts of Isolation Valve Failure on the Performance of an Urban Water Distribution System

A valve failure in a water distribution system (WDS) can cause service interruption to the water consumer around of the accident area. Thus, the impact of valve failure can be reduced by identifying valves whose failure will have the most adverse consequence on the system’s performance. This study assesses the impacts of isolation valve failures on the performance of WDS (i.e., on the number of affected customers (NAC), number of isolation elements (NIE), and system supply demand shortfall (SDS)) of WDS and proposes the methods to identify the important isolation valves. In general, it is noticed that a larger f valve density leads to a lower risk of valve failure as the stress level is small. However, it has been found that the isolation valve failure has varied effects on the WDS performance under the abnormal condition of pipe failure. This study highlights this point through a case study of Dire Dawa city (Zone 3) in Ethiopia. The results found that the isolation valves V16, V17, V66, V24, and V13 are the most critical from the system supply shortfall point of view. Finally, it is concluded that identifying the most important valves yields numerous insights that can guide isolation valve topology, pipes maintenance, and management in an urban WDS.