--- layout: single title: "Acoustic Leak Detection" categories: research tags: anomaly-detection audio-processing deep-learning signal-processing real-world-application excerpt: "Anomaly detection models for acoustic leak detection in water networks." header: teaser: /assets/figures/10_water_networks_teaser.jpg scholar_link: "https://scholar.google.de/citations?user=NODAd94AAAAJ&hl=en" ---  {:style="display:block; width:40%" .align-right} Detecting leaks in vast municipal water distribution networks is critical for resource conservation and infrastructure maintenance. This study introduces and evaluates an **anomaly detection approach for acoustic leak identification**, specifically designed with **energy efficiency** and **ease of deployment** as key considerations. The methodology leverages acoustic recordings captured by microphones deployed directly on a section of a real-world **municipal water network**. Instead of requiring continuous monitoring, the proposed system mimics human inspection routines by performing **intermittent checks**, significantly reducing power consumption and data load. Various **anomaly detection models**, ranging from traditional "shallow" methods (e.g., GMMs, OC-SVMs) to more complex **deep learning architectures** (e.g., autoencoders, potentially CNNs on spectrograms), were trained using data representing normal network operation. These models were then evaluated on their ability to distinguish anomalous sounds indicative of leaks. Key findings include: * Detecting leaks occurring acoustically **nearby** the sensor proved relatively straightforward for most evaluated models. * **Neural network-based methods demonstrated superior performance** in identifying leaks originating **further away** from the sensor, showcasing their ability to capture more subtle acoustic signatures amidst background noise. <center> <img src="/assets/figures/10_water_networks_mel.jpg" alt="Mel-spectrogram examples showing acoustic signatures of normal operation versus leak sounds" style="display:block; width:90%"> <figcaption>Mel-spectrogram visualizations comparing normal sounds and leak-related acoustic patterns.</figcaption> </center><br> This research validates the feasibility of using anomaly detection for practical, energy-efficient acoustic leak monitoring in water networks, highlighting the advantages of deep learning techniques for detecting more challenging, distant leaks. {% cite muller2021acoustic %}