Terra15 provides leak detection service to Water Corporation in Perth CBD

• 30km network of fibre-optic cable used to listen for water leaks
• WA-developed solution detects hidden leaks before they become more significant bursts
• Part of $184.7 million investment in Perth metro water network to improve resilience and save water

Hidden technology beneath your feet is listening for water leaks in the Perth CBD, in a new, Australia-first project by Water Corporation.

The cutting-edge distributed acoustic sensing technology by Perth-based Terra15 Technologies turns existing fibre-optic cable in the city into a giant acoustic leak detection network to detect water leaks before a pipe bursts.

Laser light is pulsed through a thin strand of fibre-optic cable, no thicker than a human hair, which detects any minute interruptions in the signal due to vibration or sound.

Programmed to listen for the distinctive sound of a leak in nearby water mains, the technology enables Water Corporation to fix the pipe long before it bursts, saving valuable water, money and more significant disruption.

The equipment is so sensitive it can detect regional earthquakes, as well as the background noise of footsteps, traffic and construction work. It can also detect tampering or theft on a pipeline.

Water Corporation General Manager Assets Planning and Delivery Evan Hambleton says the technology will help improve the reliability of the CBD water supply and reduce reactive repair work, costing $12.5 million within the metro area in the last financial year (FY22-23) alone.

“While we are progressively upgrading the Perth CBD water network, some leakage is unavoidable with sections of our old cast iron pipes dating back more than 100 years.

“This clever technology, which uses spare capacity in existing telecommunications fibre-optic cable, causes the fibre to behave like thousands of vibration sensors, or acoustic loggers, spread out over many tens of kilometres.

“Sensitive enough to detect a tiny leak quickly and track it over time, it will enable us to fix the pipe long before any water would be visible at the surface, preventing a much more damaging and disruptive burst.

“Water Corporation has a proven track record of innovation in the Australian water industry and this technology will help improve the resilience of the Perth CBD supply and save taxpayer money.”

The project is on top of Water Corporation’s planned $184.7 million investment (FY23-24) in the metro water network and supply projects, including its current
$10 million project to replace ageing water mains around the Kaarta Gar-up (Mount Eliza) reservoir in Kings Park under its Pipes for Perth program.

For more information on Perth’s water supply, visit: www.watercorporation.com.au/Our-water/Climate-change-and-WA/Climate-and-Perth/Securing-supply

What is DAS?: terra15.com.au/what-is-distributed-acoustic-sensing-das/

Distributed Acoustic Sensing fact file

• Distributed Acoustic Sensing (DAS) system turns fibre-optic cable into a giant acoustic sensor that records tiny stretches in the cable’s optical fibre caused by vibration or sound – everything from a high-pitched leaky pipe or squeaky bearing to a low-pitched earthquake.
• Pulses a laser thousands of times per second into a fibre-optic cable to measure the light refracted off microscopic imperfections in the fibre (Rayleigh backscatter).
• This records a ‘fingerprint’ of the fibre with every pulse and comparing ‘fingerprints’ calculates how much the fibre has stretched between two pulses.
• By repeating this process thousands of times per second, it continuously measures tiny stretches of the fibre in real time – sensitive enough to detect one metre of fibre stretching by less than the width of a human hair.
• With a wide frequency range, it’s able to detect vibrations through the ground or air from hundreds of metres away to hundreds of kilometres, in the case of earthquakes.
• Unlike a microphone, it senses these sounds at thousands of points along the fibre to determine exactly where it is coming from, within metres.
• Aside from pipelines, other DAS monitoring applications include: seismic events; perimeter security; smart city eg. construction, utilities or traffic; and industrial eg. oil and gas wells, conveyors and rolling stock.