Abstract: A system for estimating water leakage position in a water supply system consisting of a plurality of water feed/distribution devices. The system includes a memory unit for storing given constants of the plurality of devices at a monitoring position, a monitoring unit for monitoring vibrating frequency of the plurality of devices, and an estimating unit for estimating water leakage position based on the stored given constants of the plurality of devices and the monitored vibrating frequency of the plurality of devices.

Abstract: A sensor detects a vibration generated due to water leakage. An integration circuit integrates time intervals for which a signal obtained by absolute-value amplifying an output signal from the sensor exceeds a predetermined level within a predetermined period of time. The integration circuit performs the integration a plurality of times. A detection circuit selects a minimum value of a plurality of integration values obtained by the plurality of measurements as an integration value obtained when the influence of unrelated noise is at a minimum and compares the minimum value with a preset reference value. When the minimum value exceeds the reference value, the detection circuit determines the presence of water leakage, and when the minimum value is smaller than the reference value, determines the absence of water leakage.