Southern Water is utilizing fiber-optic telecommunications infrastructure as subterranean sensors to identify leaks within its water distribution network.
The utility is piloting Lightsonic’s detection system, which leverages Openreach’s fiber network to locate leaking pipes. Openreach, BT’s infrastructure division, and Affinity Water, serving parts of southern England, conducted a joint trial in March.
As previously reported by The Register, the technology monitors minute variations in light propagation through fiber-optic cables to identify vibrations indicative of underground leaks. Machine learning algorithms filter out interference from traffic, construction, and other ambient noise to pinpoint escape locations.
Lightsonic asserts that the generated location data enables faster inspection and repair, claiming the system currently prevents the loss of over four million liters—approximately one million gallons—of water daily across 650 kilometers (400 miles) of UK water infrastructure.
Southern Water initiated the trial following one of Britain’s hottest and driest summers on record, during which nearly three-quarters of England faced official drought conditions. Southern England remains among the nation’s most water-stressed regions.
The utility cited Lightsonic’s prior collaboration with Affinity Water and Openreach as a key factor in its decision to proceed with the pilot.
Southern Water expects the trial to support its compliance with Ofwat’s 2030 leakage-reduction targets and enhance drought resilience by reducing pressure on reservoirs and water abstraction sources.
The company delivers water and wastewater services across Hampshire, the Isle of Wight, West Sussex, East Sussex, and Kent.
“We have reduced leakage across our network for three consecutive years and continue to invest in innovative techniques and technologies to detect and repair leaks more effectively,” said Wayne Novelli, Southern Water’s leakage and network strategy manager.
“We were impressed by the leakage reduction metrics and demonstrated success of Lightsonic’s technology, and we look forward to collaborating with the team to trial this new detection and remediation approach.”
Southern Water’s water conservation efforts occur amid a mixed environmental record. A court this week imposed a £2.4 million ($3.1 million) fine for multiple pollution incidents in Kent, following a £7.1 million ($9.4 million) penalty in July for illegal sewage discharges that closed Thanet beaches. Both prosecutions were brought by the Environment Agency.
