The Sensors Beneath Europe’s Water Revolution

European utilities use in-pipe sensing to reveal hidden leaks, reduce losses, and accelerate the shift toward data-driven water maintenance

13 Oct 2025

Europe’s water utilities are increasingly turning to in-pipe inspection technologies as they confront rising leakage rates in aging networks and growing pressure to use resources more efficiently.

Across much of the region, non-revenue water, meaning water produced but not billed because of leaks or theft, remains a structural problem. In some European systems, losses are estimated to exceed 20 per cent. Climate stress, urban growth and decades-old infrastructure have made the issue harder to ignore, while regulators are asking utilities to demonstrate clearer returns on infrastructure spending.

One response has been the use of advanced inspection tools that operate from inside large transmission pipes. Utilities in several European countries have begun deploying acoustic sensing devices that travel with the water flow, collecting data without interrupting supply. The approach contrasts with traditional methods such as surface listening or pressure testing, which often struggle to detect leaks deep underground, particularly in large-diameter mains.

Municipal operators have partnered with companies including SUEZ and Aganova to inspect pipelines that have historically been difficult or costly to monitor. In multiple deployments, the systems have identified dozens of previously undetected leaks, including clusters of small but persistent failures that would not have triggered alarms using conventional techniques.

The devices capture acoustic signals generated by escaping water. Once analysed, the data can indicate the location and likely severity of defects, allowing operators to distinguish between urgent repairs and issues that can be addressed later. Utilities say this helps them prioritise interventions, reduce unnecessary excavation and limit service disruption.

The greater visibility is influencing maintenance strategies. Rather than relying on reactive repairs or broad replacement programmes, operators are increasingly targeting investment where the data show the highest risk or loss. The ability to produce auditable evidence is also becoming more important as public scrutiny of infrastructure spending intensifies.

The technology is not without limits. In-pipe inspections require careful planning, skilled data interpretation and integration with existing asset management systems. Utilities caution that the tools complement, rather than replace, other monitoring methods.

Even so, many operators see in-pipe sensing as part of a broader shift towards precision maintenance. As Europe seeks to secure water supplies under tighter environmental and financial constraints, making hidden losses visible is becoming a central part of network management.