An innovative solution developed by leading consultancy WRc with the support of the Technology Strategy Board looks set to make the identification and tracing of leaks in smaller pipes a more accurate, faster and cost-effective process.

Millions of pounds go down the drain every year while water companies search for the holy grail of the business - finding the leaks. As much as 40% of some countries' water supply pours straight into the ground - in the UK, over 3bn litres are lost every day through leaks.

WRc was one of ten companies that were awarded funding in a Technology Strategy Board competition on water security.

The consultancy received £48k for a feasibility study of technologies that might speed up the process of finding and mapping leaks in pipes less than 100mm in width. The project was called INFO-Leak.

WRc already runs Sahara, an international service for detecting leaks in large water mains which involves putting a microphone on a cable into the water supply and listening for leaks. Operators walk above tracking the position of the acoustic detectors in the pipes.

The organisation wanted to develop technology that would allow it to offer a similar service for smaller mains and reduce the cost of running the existing Sahara service. The Technology Strategy Board funding helped the company to carry out a feasibility study that led to the development of new technology

‘We knew this technology had world-wide application with significant export potential. If successful, the developed technology could, in one year, save more water than is needed every day for a city the size of Sheffield,' explained Julia Trew, Senior Project Manager for INFO-Leak.

Leaks in the pipes that run under streets and carry water to houses are notoriously difficult to find. Finding them has involved monitoring changes in water flows at night when not much water is used with engineers then going to suspect areas and listen for water escaping.

While the system works well enough for metal pipes, locating holes in plastic ones, which are increasingly being used in local mains, is much more hit and miss. The process can often involve days of digging to locate a hole in a pipe.

Julia Trew continued:

‘There is a need for a leak detection method for use in the distribution network which allows quicker detection of leaks and is more accurate in pinpointing the exact location.”

‘We wanted to investigate the possibility of replacing that with a lighter, thinner system using a camera and inertial navigation instead of having someone walking on top of the main.'

The initial feasibility study looked at a combination of three different technologies: fibre optic sound detection; inertial navigation; and live entry of tethered sensors to produce a new small diameter leak location system.

When it became apparent that inertial navigation and fibre optic cable weren't close enough to market, the Technology Strategy Board allowed WRc to reallocate the unspent money to looking at alternatives.

WRc instead opted for a miniaturised version of the piezo-electric noise detection equipment used on the Sahara system. For location along the main, the final solution uses extra low-flow magnetics, a technique that makes use of a magnetic sensor coupled to some interface electronics inside the pipe.

WRc is now currently trialling a prototype. The feasibility study may also result in the new technology being applied to larger pipes with improved efficiency in operations.

Julia Trew added:

‘The Technology Strategy Board helped WRc to carry out valuable research that will help businesses safeguard future water supply, both in this country and abroad.'