The most common way to find a leak under soil or concrete involves high-powered microphones. When a pressurized pipe breaks, the water rushing out creates a distinct vibration and sound. These sounds travel through the pipe walls and the surrounding earth. Plumbers use ground microphones and listening discs to pick up these frequencies. Acoustic equipment filters out background noi... https://bluepacificcapecod.com/how-does-a-plumber-find-a-water-leak-underground/