Acoustic Leak Detection Explained
How a ground microphone actually finds a leak — not just marketing language, the real mechanics.
How Acoustic Leak Detection Actually Works
Water escaping a pressurized pipe makes a specific, identifiable sound — different from ambient noise like traffic, HVAC systems, or foot traffic. A ground microphone is sensitive enough to pick up that sound through concrete, soil, or drywall, and a trained ear (backed by filtering equipment) can tell the difference between a real leak signature and background noise.
In practice, this starts with listening at accessible points — meters, valves, cleanouts — to get a baseline. From there, we move the microphone across the suspected area, listening for where the sound is loudest, which usually corresponds to the closest point to the actual leak. Professional-grade equipment includes filters that isolate the specific frequency range of escaping water, screening out interference like traffic noise, wind, or nearby electrical equipment.
When Acoustic Detection Works Best
- Pressurized supply line leaks (both hot and cold water)
- Leaks under concrete slabs or driveways
- Underground water line leaks between the meter and the house
- Confirming a leak location before excavation or slab work
It’s less effective on drain lines, which usually aren’t pressurized and don’t produce the same acoustic signature — that’s where camera inspection typically works better.