Water mains leak detection for retail sites
The supply pipe between the meter and your unit runs under car parks, service yards and slab floors. When it fails, the first sign is usually the bill. We find the break from the surface, so nobody digs a trench through the customer entrance on a guess.
Every retail unit has a supply pipe it never sees. It leaves the water company’s meter at the boundary, crosses the car park or forecourt, and comes up through the slab somewhere near the plant room. On retail parks and older parades that run can be long, unmapped and shared with neighbouring units. Once it starts leaking, the water disappears into the sub-base and you pay for every litre.
Our engineers locate underground mains leaks using acoustic ground microphones, leak correlators and tracer gas, then mark the position on the surface. Where the pipe is under a trading floor, thermal imaging and tracer gas do the same job from inside without lifting the finish. You get a marked spot and a report, and where the repair is straightforward we aim to complete it on the same visit.
Signs you have one
- A water bill that has risen with no change in trading or headcount
- The meter keeps turning after every tap, urinal and appliance is off
- A permanently wet patch, moss or lush weeds in one part of the car park or service yard
- Low pressure at the taps or in the WCs, worst at busy times
- A dip, sinkhole or lifted kerb along the line of the supply pipe
- A letter from the water company about unusually high consumption
- Water surfacing at the base of an external wall or in a meter chamber that should be dry
- Damp coming up through the slab near the plant room or incoming stop tap
What we do
Confirm it is the mains
We isolate the supply at the internal stop tap and watch the meter. If it still turns, the loss is on the underground run. If it stops, the leak is inside and we switch to the plumbing survey.
Listen along the route
Ground microphones pick up the noise of pressurised water escaping through tarmac, block paving and concrete. We work along the line of the pipe, comparing readings until the sound peaks.
Correlate and confirm
On longer runs, sensors at two points on the pipe calculate the position of the leak between them. Tracer gas gives a third opinion where the ground is noisy or the pipe is deep.
Mark, report, repair
The position is marked on the surface and photographed for the report. Where the pipe is accessible we aim to excavate and repair on the same day, in one small hole rather than a trench.
Retail considerations
Car parks stay open
Listening and correlating happen from the surface with hand-held kit. We cone off a bay or two at a time, so the rest of the car park stays in use.
Whose pipe is it?
The water company usually owns the pipe up to the boundary; the leaseholder or landlord owns the rest. Our report states where the leak sits on that line, which usually settles who pays for the repair.
Multi-site estates
Facilities teams with dozens of stores get one number, the same report format on every site and an engineer based near each one. Meter readings from the store team are enough to get a survey booked.
Questions
How do you know the leak is on our pipe and not the water company’s?
The meter is the boundary. A leak between the meter and your unit is on the private supply, which is usually the leaseholder’s or landlord’s responsibility. We locate the leak and state its position relative to the meter in the report, so the question is answered before anyone picks up a spade.
Do you need to dig to find it?
No. Acoustic listening, correlation and tracer gas all work from the surface. Digging happens once, at the marked point, for the repair.
The car park is tarmac and full of cars. Can you still survey it?
Yes. Ground microphones work through tarmac and block paving, and we only need a few bays clear at a time. Early-morning surveys before the site fills up are common and easy to arrange.
How accurate is the marked position?
Accurate enough to dig one hole. Correlators and ground microphones between them narrow the leak to a small area, and tracer gas confirms it where the ground is noisy. The repair excavation is sized to the marked point rather than the length of the pipe.
Can you repair it on the same day?
Where the pipe is accessible and the repair is straightforward, we aim to. Deeper runs, pipes under structures and shared mains sometimes need a second visit or a specialist contractor, and the report gives them everything they need.
Other services.
Most engineers arrive with the full kit, so if the leak turns out to be a different kind, the survey carries on.
Heating & pipework
Commercial central heating and underfloor systems losing pressure. Tracer gas and thermal imaging find the break with the floor still in place.
See the serviceRoof & ceiling leaks
Flat roofs, rooflights, box gutters and drips from the unit above. We trace the water back to where it gets in, which is rarely where it shows up.
See the serviceUnder-floor & slab
Pipes buried in screed beneath tiles, vinyl and timber. Located from above, so the shop floor stays whole.
See the serviceWashrooms & staff areas
Customer toilets, staff kitchens and cleaners’ cupboards. Small rooms with a lot of pipework, and the source of most damp patches next door.
See the serviceDrains & CCTV surveys
Blocked, cracked or leaking drains in service yards and beneath units, surveyed with CCTV drain cameras and pressure testing.
See the serviceDamp & structural ingress
Penetrating damp, basement stock rooms and party walls. Moisture mapping shows what is a leak and what is condensation.
See the serviceWhere this comes up.
Retail parks
Long supply runs under car parks and shared service yards, often unmapped.
View sectorForecourts & convenience
Water supply and car-wash feeds beneath the hardstanding, found without breaking it up.
View sectorSupermarkets & grocery
Chillers, condensate lines and busy back-of-house plumbing on a floor that never really closes.
View sectorSpeak to the team about your leak.
One call gets a leak engineer moving. Our methods are non-invasive, so there is usually nothing to dig up, and you get a written report ready for your insurer.
Engineers across England, Scotland and Wales. £5 million public liability insurance.