Many of the waterworks facilities in Japan were constructed during the rapid economic growth period. Today, the deterioration and renovation of these aged facilities have become a pressing issue. There are approximately 600,000 km worth of water pipelines laid out across Japan, accounting for about 70% of the nation's water-related assets (totalling ¥40 trillion). To provide water that is safe to use, it is necessary to improve and innovate water purification technologies; not only that, it is also vital to properly maintain and manage the pipelines. The current research aims to apply reliability engineering in the waterworks field as one possible approach and to show its viability; it will also obtain vital messages revealed within pipeline incident data. In other words, we collected the information concerning water distribution pipeline incidents through questionnaire surveys and then analysed the cumulative failure distribution (unreliability) by pipeline material, the failure probability density and failure rate, among others.