Pilot Study of the Characteristics of Different Failure Types in Water Distribution System Pipes

Abstract

Rapid urban, economic, and population growth has led to increased water demand and reduced availability. At the same time, the condition of water distribution systems has deteriorated, and water leakage has increased. Although previous research has developed models to simulate leaks in water distribution systems, these models do not consider the distribution of varying leak types and their distribution in different pipe materials, and little is known about this topic. Therefore, this study aimed to identify the most effective pipe failure distribution for analyzing failure types in various pipe materials by using the maximum likelihood approach. The study used data on water pipe failures gathered from Auckland’s water network over six years (2017–2022) to accomplish its goal. The results show that the log-normal distribution is the best distribution for longitudinal, circumferential, and round holes, whereas the normal distribution is the best for blowout holes. Finally, the reported plus unreported failures were derived from the fitted distribution for estimated data. The study’s findings provide valuable insights into the distribution of leak types and their occurrence in different pipe materials, which can help in developing effective leak management strategies. The discussion of the study highlights the limitations and implications of the research and suggests directions for future research to improve the accuracy of the models used to simulate leaks in water distribution systems. Overall, this study contributes to the understanding of the complex issue of water leakage and provides important information for water authorities and policymakers to develop effective strategies to minimize water loss and ensure a sustainable water supply. This study offers initial insights into the type and dimensions of pipe failures occurring in different pipe materials based on photographic records of pipe repairs conducted in Auckland’s water distribution system in New Zealand. An extensive literature review of pipe failure studies revealed no previous work describing the dimensions of leaks discovered in water distribution systems. This information is critical for better understanding pipe failure types and mechanisms and the development of more realistic stochastic leakage models for water distribution systems. Such stochastic models will allow the impact of leaks on system flow rates and pressures to be investigated and provide more realistic scenarios for network simulation and evaluation of leak detection algorithms. The research only had access to a limited number of failures, and it recommends more research on the types and dimensions of leaks in water distribution systems. A better understanding of pipe failure patterns will assist water utility managers and engineers in making more informed decisions on material selection, maintenance, and repair strategies, ultimately reducing water loss and costs associated with pipe failures.