City of Tshwane, Pretoria

diameter PVC pipe

problem leak located

leakage reduction per hour

The challenge

Following a successful pilot with FIDO AI in Pretoria, the City of Tshwane Metropolitan Municipality challenged our regional partner Fontus Tech to help it find a persistent leak in the Waterkloof area of Pretoria. Despite clear signs of water loss, steep terrain was making it difficult to pinpoint accurately and efficiently. The challenge was compounded by the nature of the area: a busy, high-profile residential neighbourhood hosting several embassies and consulates, where extensive excavation or prolonged disruption was not desirable.

Although the water mains network had been upgraded around 11 years earlier from asbestos cement to 160 mm PVC, the client had already exhausted conventional approaches, including step-testing and top sounding with ground microphones.

The solution

Fontus Tech used FIDO’s versatile AI-enabled sensors in a targeted, multi-stage investigation to accurately pinpoint the source of the leak.

Given the visible water in the drain, work started by conducting FIDO AI correlations in the same street using an isolation valve and a fire hydrant. These ruled out a leak in that street so the investigation expanded to the street located above. Here, FIDO AI sensors were used to take soundings on four fire hydrants; two of which showed FFT signatures consistent with leaks in PVC/HDPE pipe material.

A camera inspection between stormwater manholes identified a possible leakage point, which was confirmed by a further sounding session at a nearby consumer meter, which immediately produced a clear leak signature in both audio and FFT outputs.

Finally, precise top-sounding was undertaken to accurately mark the leak location, avoiding blind excavation and alleviating the property owner’s concerns about damage to paved surfaces.

The results

The location identified by FIDO AI was excavated by City of Tshwane two days later and the leak was found at approximately 1.5 metres below the surface.

Following repair, the leak was estimated at around 7.2m³ per hour, with local residents reporting that it may have gone undetected for several years. This equates to an estimated annual water saving of approximately 63 million litres from a single leak.

Given that the municipality had been aware of the issue but had been unable to locate it using traditional detection methods, the accuracy of the solution and the speed at which the leak was identified were particularly noteworthy.

City of Tshwane is now considering the use of Fontus Tech and FIDO AI technologies for future leak investigations.