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若要减少水源损耗和日常开支，那么，检测漏隙、维修供水网络便变得日趋重要。在这种工作中，检测漏隙并确定漏隙位置是首要任务。如果想成功地进行挖掘工作的话，定位应精确到实际位置的±１米之内。 我们已经发展了一种称为ＬＯＣＡＬ的检测和定位方法，该方法利用流体通过漏隙时的流动噪声。漏隙位置的信息根据信号到达两个接收器的传播时间之差（互相关法），或信号到达一个接收器的直达时间与反射物回波时间之差（自相关法）。这种方法基本上是应根据水听器信号之间的相关。 此法已被推广到供水专家所用的检修系统。具体实施时，可通过计算机控制来消除由网络中的反射物和其他噪声源引起的相关模糊度。通过互功率谱的ＦＦＴ分析和整形、来重构相关函数，这样就可改善信噪比、消除网络耗散、提高预测位置的精确度。
To reduce water loss and daily expenses, it is becoming increasingly important to detect leaks and repair water networks. In this type of work, detecting leaks and determining the location of leaks is the number one priority. If you want to successfully dig the work, the positioning should be accurate to the actual location of ± 1 m. We have developed a detection and localization method called LOCAL that exploits the flow noise when fluid passes through a leak. The information on the location of the leak is based on the difference (cross-correlation) between the propagation time of the signal arriving at the two receivers or the difference (autocorrelation) between the time of arrival of the signal at the receiver and the echo time of the reflector. This method is basically based on the correlation between hydrophone signals. This method has been extended to maintenance systems used by water supply specialists. In practical implementation, the relative ambiguities caused by reflections in the network and other noise sources can be eliminated by computer control. The correlation function is reconstructed by FFT analysis and shaping of the cross-power spectrum, thus improving the signal-to-noise ratio, eliminating network dissipation, and improving the accuracy of predicted locations.