Fiber-Optic Pilot Saves Two Million Liters a Day

Openreach and Affinity Water used fiber-optic cables to find 100-plus leaks, saving 2 million liters daily in a 3-month UK pilot

21 Apr 2026

Openreach and Affinity Water have completed a three-month trial using existing underground fibre-optic cables to identify bursts in water mains. The pilot, conducted alongside the technology firm Lightsonic, used sensors to monitor vibrations along the network to pinpoint pipe failures without the need for new construction.

The technology relies on Distributed Acoustic Sensing. This system sends light pulses through spare fibre capacity to detect the distinct acoustic signatures of escaping water. Machine learning algorithms are then used to distinguish these vibrations from routine urban noise such as road traffic or construction work.

During the test period across five UK locations, Affinity Water identified and repaired more than 100 leaks. The company estimates the daily water savings are equivalent to the supply required for 10,000 people. If expanded, the system could save more than 700m litres of treated water annually.

The trial addresses a persistent challenge for the UK utility sector. Approximately 3bn litres of water are lost to leaks every day in England and Wales, representing roughly 20 per cent of the total supply. Current detection methods often rely on manual surveys which are labour intensive and reactive.

"The results of this trial are a significant step forward," a spokesperson for the project noted. Openreach confirmed that the monitoring hardware attaches to existing fibre terminals and does not interfere with internet traffic for its customers.

For regulators and water companies, the success of the pilot offers a path toward meeting national targets to halve leakage rates. Rather than investing in bespoke sensor networks, utilities may increasingly look to share existing digital infrastructure. Openreach is now evaluating whether the technology can be deployed across its active national network.

While the initial results are promising, the long term viability of the project will depend on broader commercial agreements between telecommunications providers and water utilities. Future integration will require clear frameworks for data sharing and infrastructure costs as the sector seeks to modernise its ageing assets.