Southern Water is trialling Lightsonics’ leak-detection system in Hampshire as drought in the United Kingdom puts more pressure on water losses. The test uses Openreach’s existing fibre optic network to spot leaking mains faster and push repairs toward targeted interventions.
The system reads changes in light along cables and uses machine-learning filters to separate leak signatures from traffic and roadworks noise. A previous 650 km UK trial reportedly cut losses by over four million litres per day, giving the Hampshire trial a measured benchmark rather than a theoretical promise.
Openreach fibre in Hampshire
Openreach’s network gives the trial a ready-made route across the ground, so the leak-detection equipment does not need a separate line laid before it can work. Lightsonics’ method looks for vibration patterns from nearby leaking mains, then estimates where those leaks are likely to sit.
Southern Water and Lightsonics are using that setup to move from proof-of-concept into operational scale. The practical benefit for customers is narrower digging and fewer broad surveys when crews are trying to find a hidden leak.
River Test and losses
The earlier 650 km UK trial also pointed to a second effect: less water lost before repairs begin. The source says that kind of reduction could ease abstraction from sensitive sources such as the River Test and defer some network replacement, which matters because every litre not lost is a litre the system does not need to replace elsewhere.
That leaves the Hampshire work with a clear operational test. Southern Water is not just checking whether the system can detect a leak; it is checking whether the method can deliver enough precision to change how crews search, repair and prioritise the network.
The deployment already carries a built-in tension: it is being presented as operational, yet Hampshire is still described as a trial. For customers, the immediate question is whether the method keeps proving itself quickly enough to move from a local test into wider use across the south of England.
