Water mains leak detection in Wales

Water mains leak detection finds hidden leaks in underground supply pipes using acoustic ground microphones, tracer gas and pressure testing.

029 2190 0328

Engineer turning an external stop tap in a grass verge

Non-invasive leak detection
Acoustic, thermal and tracer gas
Trace and access claim reports

What are the signs of a water mains leak?

A meter turning with every tap off, rising bills or wet ground can indicate a leak. ADI Leak Detection Wales locates and marks the leak before digging begins.

A supply pipe leak is underground, so the signs below are usually all you see of it:

The meter dial moves when every tap and appliance in the house is off
A water bill that has climbed with no change in how much water you use
Pressure that drops away when more than one outlet runs
Wet ground, sinking block paving or a patch of lawn that stays green in July
A leak notification letter from your water company through the door

If the water is going from the garden watering pipes, irrigation leak detection tests those. A falling pool level calls for swimming pool leak detection to test the pool shell and circulation pipework.

Where do water mains leaks occur in Wales?

Water mains leak detection investigates water escaping from the pipe supplying a property.

Dŵr Cymru Welsh Water serves most of Wales, while Hafren Dyfrdwy supplies parts of Wrexham, Powys, Denbighshire and Flintshire.
Give the advisor the supplier shown on your bill and describe any meter movement or loss of pressure.
If a pipe crosses a shared entrance or supplies another building, explain what you know about its route and who can arrange access.

How does ADI Leak Detection Wales find a water mains leak?

The engineer isolates and pressure tests the supply pipe, listens along its route with ground microphones and confirms the leak with tracer gas before marking it. Once the position is found, the engineer explains it on site before any repair is discussed.

The pipe is usually a metre down and the sound of it travels, so tracing it first helps you avoid unnecessary digging.

Isolate and pressure test the water mains pipe

Pressure test rig with gauges and isolation valves on paving during leak detection

Pressure testing confirms and measures water loss from the mains pipe. The engineer first isolates the supply at the boundary stop tap, then tests the pipe before tracing the leak.

Listen along the pipe using acoustic listening devices

acoustic leak detector and ground microphone on brick paving driveway during leak detection investigation

Acoustic ground microphones pick up the sound of water escaping beneath the surface. The engineer moves them along the pipe route in short steps.

Confirm the water mains leak with tracer gas

Tracer gas cylinder and hose reel connected to external pipework during leak detection

Hydrogen tracer gas is introduced into the isolated mains pipe and detected at the surface above the escape. The engineer uses this method where ground noise or a slab affects the search.

Locate the water mains leak

Leak position marked with a painted cross on a lawn

The water mains leak position is marked on the ground and measured back to a fixed point, so whoever digs knows where to open up.

Who fixes a leak on your supply pipe, you or the water company?

Responsibility for a supply pipe changes at the property boundary. Which water company serves your property depends on your town, and each town page names it, its leak line and its published guidance.

ADI Leak Detection van parked outside a brick house

What happens after a water mains leak is found?

Water mains leak repairs by ADI Leak Detection Wales are guaranteed. If the leak is on the water company's side of the boundary stop tap, the report identifies that so you can pass it to them.

Every leak detection visit ends with a written report by the engineer who attended, with photographs and video, formatted for trace and access and escape of water insurance claims.

The leak position marked on site and explained before you decide anything
Photographs and video in the written report

See every area we cover, by district and postcode.

How do you arrange water mains leak detection in Wales?

Send the form with your postcode and a technical advisor will call you back, confirm the service and book the visit.

If you are unsure which investigation you need, describe what you can see when you call and the advisor will tell you.

Tell us what is leaking

Same or next day depending upon engineer availability.

What do people ask about water mains leak detection?

Four questions come up before a water mains survey: how long it takes, who owns the pipe, whether the driveway gets dug up and how the leak is pinpointed underground.

How long does a water mains leak detection visit take?

It depends on the property and how much of the system has to be tested, so the advisor gives you an estimate when you book.

Who is responsible for a leaking water main in Wales?

Your side of the boundary stop tap is yours and the street side is the water company’s; each town page names the company for that town, and the report says which side the leak is on.

Does finding a water mains leak mean digging up the driveway?

Water mains leak detection traces the pipe from the surface with acoustics, tracer gas and a pressure test. Digging happens once, at the marked point, only if you want the repair done.

What is leak noise correlation?

Leak noise correlation is a way of estimating where a leak sits on a buried pipe. Two sensors are clamped to fittings at either end of the run, the leak noise reaches each one at a slightly different moment, and the time difference gives a distance along the pipe. ADI Leak Detection Wales finds water mains leaks with acoustic ground microphones, tracer gas and pressure testing.