The urban population grappling with water scarcity is projected to reach two billion people by 2050. Therefore, mitigating leaks in the water distribution networks (WDNs) becomes crucial for better future water security. This review article summarizes the present detection capabilities concerning small leaks (less than 1 L/s). The scope of the review encompasses experiments and simulations carried out using in-pipe robots as well as sensor networks that are capable of continuous monitoring. This aids future research efforts in gaining a clearer understanding of existing detection techniques’ strengths and limitations with small-leak detections.
