An Inline Impedance-Based Leakage Detection Method for Nonconducting Buried Water Mains

The ability to detect small leakages in plastic pipes is imperative to ensure water security for the near future, yet it remains challenging. This study seeks to address this challenge by proposing an innovative in-line leakage detection and localization technique based on differences in electrical impedance. The technique is highly sensitive to small leaks, inexpensive, and relatively easy to implement. We analyzed the circuit model to explain the high sensitivity. The model shows that the sensitivity of the sensor for leaks is theoretically very high. Furthermore, a field experiment is presented, validating the detection capability for small leaks (below 0.01 L/s at 0.5 bar) and the localization method. The experiment was conducted using a plastic pipe representative of many that are currently used in the water distribution mains. Finally, the characteristics of the detection signal are shown, and sensor design recommendations are made.