Service
Underground Leak Detection — Pretoria & Gauteng
When your water bill jumps, the ground is soggy in one spot, or the municipality has flagged consumption that doesn't match your occupancy — the leak is almost always underground on the service line running from the erf boundary to the house. Finding it without digging up a driveway or lifting a lawn is the job. This is the page for that service.
What underground leak detection actually involves
Underground water leak detection is a diagnostic session, not a repair. Our job is to identify exactly where in the buried pipe run the water is escaping, mark that point on the ground with a GPS pinpoint and a photograph, and hand the finding to a plumber who can dig a targeted trench of one to two metres rather than opening the whole run. The value of the diagnostic is in the precision of the pinpoint — we routinely mark leaks inside a metre, sometimes within a hand-span.
The session takes about two hours on a standard residential property and R1,850 flat covers every step. On confirmed leaks — meter turning, water use zero at the tap — that we cannot locate with our full detection kit, you receive a full refund under the No Find, No Fee guarantee.
The four detection methods, and when we use each
Acoustic ground microphone
Our primary tool on rigid pipe. Copper, galvanised, and older brass fittings all ring cleanly when pressurised water escapes through a failure joint — the sound conducts through slab, soil, and paving in a characteristic signature the microphone identifies against background noise. Best on paved driveways, concrete slabs, and close to the boundary meter. Less useful on flexible pipe like HDPE, and less useful under heavy mulch or lawn where the sound attenuates before reaching the surface.
Tracer gas — hydrogen–nitrogen mix
Where acoustic struggles, tracer gas leads. We inject a safe hydrogen–nitrogen blend into the isolated pipe run through a fitting at the isolator. The gas rises through soil to the surface wherever the pipe is open, and a surface detector reads the concentration at ground level. This is our go-to tool on HDPE, on landscaped gardens, under mulch, and under grass. It works regardless of ground moisture and doesn't care about acoustic background noise.
Correlator
For long buried mains runs — typical on legacy Bryanston stands or estate reticulation — we deploy a pair of sensors placed on either end of the suspect section. The correlator triangulates the leak by measuring the time-delay of the acoustic signature between the two sensors. Useful when the pipe run exceeds twenty metres and the acoustic microphone alone can't narrow the location fast enough.
Thermal imaging
Hot-line leaks (from the geyser to the house or the geyser to the taps) light up thermally against the surrounding cold structure. We use a thermal imaging camera on any suspected hot leak — a warm patch under a floor tile, damp on a wall against an outside surface, or a musty smell in a cupboard against an outside wall. Fast to read, works through plaster, and doesn't require access to the pipe itself.
How we sequence the session on your property
Meter test comes first, always. If the municipal meter dial is turning with every tap and appliance closed, the leak is confirmed and we proceed. We then choose the first tool based on what we see — pipe material, ground conditions, symptom pattern — and switch tools as needed within the two-hour window. On a standard Pretoria residential property we typically resolve to a pinpoint on a single visit; on complex or long-run properties we use the full two hours. Where the diagnostic requires more than two hours (long legacy stands, complex reticulation, extensive landscaping), we may propose an extended session at additional cost — this is documented on the service terms page and quoted before the appointment starts.
Once the pinpoint is marked, we photograph the location, record GPS coordinates, and document the diagnostic sequence in the report. The report is emailed within two business days and includes a repair quote for the specific pipe section identified.
What you can expect from the report
Every underground leak detection report contains: timestamped meter readings before and after the diagnostic, photographs of the pinpoint from multiple angles, GPS coordinates at metre-level resolution, a summary of the methods used, and a repair quote for the identified section. On insurance claims, the same report format has been accepted by every South African insurer we have worked with — we hand the report over ready to submit.
Read our suburb-specific pages for the local detail — Waterkloof, Centurion, or Rivonia each cover their plumbing generations in specific detail. The full list is at the water locations hub.
No Find, No Fee
On a confirmed leak — meter turning with taps closed, or a measurable pressure drop on your pool circuit — if we cannot locate the source, you receive a full refund.
Read the full No Find, No Fee terms →