Acoustic Leak Detection in London and Surrey
A pressurised leak makes a noise. With the right equipment and a quiet moment, that noise gives away the position of the leak under floors, driveways and gardens.
Acoustic leak detection uses ground microphones, contact sensors and amplified listening equipment to pick up the sound of water escaping from a pressurised pipe. The engineer listens at intervals along the pipe route and homes in on the point of loudest, most consistent signal. On longer buried runs the position can be refined by comparing the signal at two points. It is one of the methods DML uses, where appropriate, as part of a wider leak investigation.
Where acoustic methods work best
- Underground mains supply pipes from the boundary stopcock to the property
- Pressurised central heating circuits under solid floors
- Rising mains and distribution pipework in blocks and commercial buildings
- Confirming a position before excavation or opening up
- Properties where Thames Water or another supplier has reported high usage or a suspected leak on the private side
Limits, stated honestly
Acoustic detection depends on pressure, pipe material, depth and background noise. Plastic pipes transmit less sound than metal; deep or very slow leaks can be quiet; busy roads mask the signal. For these reasons we often combine acoustic listening with tracer gas or thermal imaging, and we will tell you when a method is not suitable rather than guess.
What you receive
A report with the located position, the evidence behind it, the recommended excavation or access point and a repair scope. Repairs are quoted separately by our team or any contractor. Where the leak sits on the private side of a water supply, the report supports your application to the water company and any insurance claim.
We investigate across Greater London and Surrey. See areas we cover.
Frequently Asked Questions
How accurate is acoustic leak detection?
On metal pipes under favourable conditions, typically within a short distance of the leak. We confirm with a second method before anyone digs.
Does it damage anything?
No. It is entirely non-invasive. Nothing is opened up until the position is confirmed.
Can you find a leak under a concrete driveway?
Yes, where the pipe is pressurised. Depth and material affect the signal, which is why we may add tracer gas.
Thames Water say the leak is on my side. What now?
Book an investigation. We locate it, document it and give you the evidence for the water company and your insurer, and a repair scope for your contractor.
Do you excavate and repair?
DML locates and reports. Excavation and repair are quoted separately by our team or your own contractor.
Related services
- Leak detection
- Tracer gas leak detection
- Water mains supply pipe leaks
- Water authorities and private-side leaks
- Trace and access
Related reading: How thermal imaging leak detection works · Supply pipe leaks: yours or Thames Water’s?
Locate it before you dig
Independent acoustic and combined-method leak detection across London and Surrey.
Last reviewed: 26 October 2026. Independent investigation and written reports. Repairs are quoted separately.