Fibre optics could be the answer to water loss from leaky pipes

Approximately 48.6 billion cubic meters of water are lost around the world every day. According to the International Water Association (IWA), the main culprits for this loss are underground leaks on water mains and service pipes.

To monitor leaks in water pipeline networks, researchers at the Polytechnic University of Milan have experimented with a novel method using fibre optics — the inexpensive and commonly- used technology that allows us to have fast internet at home.

The scientists developed a distributed fibre optic sensing (DFOS) cable based on the so-called Stimulated Brillouin Scattering (SBS) technology, which enables the processing and storage of optical information. They worked on High Density Polyethylene (HDPE) pipes, the mainstream water-conveying system for civil, agricultural, and industrial purposes.

To test the fibre optic cable’s ability to detect deformation caused by pressure anomalies along a pipe (such as the ones resulting from water leaks), the team wrapped and mounted it on the pipe’s outer surface.

The experiment comprised two main phases. First off, the scientists assessed the sensitivity of the sensor layout on an HDPE pipe that was stressed with static pressure.

“This first stage was successful, so we then concentrated on detecting the pressure anomaly produced by a leak in a piping circuit with flowing water,” explained the researchers. “Overall, the results returned positive feedback on the use of DFOS, confirming the possibility of identifying and localising even very small water leaks.”

The team is planning to further develop their monitoring solution and work towards the production of industrial-scale, “natively smart” HDPE pipes with an integrated DFOS cable. Using machine learning algorithms to interpret the cable’s data could also lead to a leak prediction model.

While water tech still receives only a silver of funding, it will play a crucial role in managing our natural resources — especially in a climate crisis-struck world.