FIELD VALIDATION OF ACOUSTIC LEAK DETECTION IN AN AGING URBAN WATER DISTRIBUTION SYSTEM: INFLUENCE OF AGING INFRASTRUCTURE ON ACOUSTIC LEAK DETECTION

Water losses in distribution networks pose a major challenge for regional water utilities, exacerbated by aging infrastructure and the increasing frequency of failures in pipeline sections beyond their service life. This paper presents two case studies on field validation of acoustic leak detection in an urban water distribution system, focusing on how pipe materials influence signal propagation and localization efficiency. Investigations were carried out on representative sectors, including old metallic pipelines affected by corrosion, deposits, and deteriorated joints, as well as rehabilitated/replaced sections using high-density polyethylene (HDPE) pipes. The methodology involved the use of acoustic correlators and dedicated sensing equipment, followed by targeted field verification and, where required, confirmation through controlled excavations. The results highlight significant differences between the acoustic behavior of aged and modern pipelines: in legacy networks, losses are typically associated with structural defects and vulnerable joints, while background noise and pressure variability can mask leak signals; conversely, on HDPE sections, signal attenuation requires adjustment of instrument settings and measurement spacing, yet the material’s reliability reduces the likelihood of major failures. The study demonstrates that real-world validation, correlated with pipe material type and degradation condition, enables optimization of interventions and supports risk- and performance-based rehabilitation decisions, contributing to NRW reduction and improved operational efficiency.