Specialists in Trunk Main Leak Detection

Aqua Analytics is the leading trunk main leak detection services provider in Australia and New Zealand. Our professional and data-driven approach to water network management projects, sees us regularly engaged by the leading water utilities and municipalities in the region to reduce leaks on their large pipes.


Active detection of water leaks on large diameter pipelines is a crucial aspect of non-revenue water management in water supply networks. The systematic use of technology and skill to survey large diameter trunk main assets allows us to identify leaks that do not present themselves during routine water utility inspections and many are buried and never surface for customer reporting.

Aqua Analytics relies on high-powered advanced leak noise correlators, that can include hydrophones or accelerometers, to deliver trunk main leak detection services.

Virtually every water utility has at some point experienced a catastrophic failure of a large-diameter trunk main, resulting in damage to both the water main itself and the surrounding infrastructure.

Some of the current methods for detection of trunk main leaks involves inserting a microphone inside a pipe and having it carried by the flow of water. A leak is identified when the microphone passes by its location and an audible leak signature is detected. While this technology is effective, it has drawbacks that limit its use such as flow-rates, access, enabling and inspection cost.

Aqua Analytics uses advanced leak noise correlation technology that is effective on large-diameter trunk mains. These devices can be deployed on diameters 300mm and above and utilise either accelerometers or hydrophones.

Ready to learn more about trunk main leak detection?

Get in touch with the Aqua Analytics team today to determine how our technicians can support your water utility project and reduce water leakage.


Years Experience

In helping water utilities throughout Australia and New Zealand better manage their water networks with technology.


Kilometres of Leak Detection

Our team has completed over 150,000 km of active water main leak detection throughout Australia and New Zealand.

The Value of Large Diameter Leak Detection

A trunk main is intended to transport large quantities of water across water supply areas, taking water from reservoirs to treatment plants, and finally to the head of reticulated systems.

These are often referred to as the arteries of water supply systems that have an outsized consequence should they fail. Identifying leaks on trunk mains is a prudent asset management measure to prevent larger disruptive failures that can cause millions of dollars in damage.

By working with Aqua Analytics, you’re engaging one of the regions most experienced and knowledgeable teams to implement an active leak detection project. It’s our innovative processes and leak detection methodologies that allow us to continue to stay at the forefront of the industry; providing comprehensive, reliable and industry-leading services.

With higher processing speeds, improved signal processing technology, increased sensitivity and the possibility of unlimited correlation, our trunk main correlator can detect even quiet leak noise at low frequencies and can therefore accurately pinpoint leaks even in the most challenging conditions, particularly on large diameter pipes (trunk mains), non-metallic pipes and over longer distances than before.

With its powerful radio transmission, the TM2 correlator can correlate leaks over distances of 1 km or more. If required, hydrophones can be attached to a hydrant or tapping in the pipe and provide additional sound input.

TM2 boasts a completely revamped software package with a host of new and improved functions, making this the most powerful correlator on the market. When activated, the “Auto Filter” automatically selects the most relevant frequencies in order to generate an accentuated correlation peak, even for faint signals. The “Spot Filter” is a brand-new and unique feature letting the operator click on the area of the pipe where a leak is suspected, and the correlator focuses on the noise profile of that confined area. The “Notch Filtering” function removes electrical mains noises from the sound spectrum, including higher harmonics. The operator can either listen stereo to both sensors or to each sensor individually. Furthermore, the new “Filtered Listening” feature lets you listen to the leak sound file with selected filters applied. This is ideal for suppressing ambient noise like road traffic or electrical interferences.

Engaging Aqua Analytics to use the TM2 is non-invasive and non-destructive. The setup is easy with magnetic connectivity of the stainless steel accelerometer sensors and with radio communication, allowing the operator to close the manhole covers for longer day correlations or correlations overnight, and avoiding tripping on cables. No more additional costs required: No costly pipeline inspections involving pipe tapping and drilling access channels, no risk of water contamination or lost devices from internal technologies

What are the key steps for a successful leak detection project?

Alignment with utility goals – ensuring the team you engage is working towards solving your problems and contributing towards all strategic goals of your utility (for example, our teams undergo customer service training given they have regular contact with domestic and commercial water customers).

Industry-leading equipment – a robust ‘leakage toolbox’ that includes listening sticks, ground microphones, leak noise correlators and acoustic leak detection devices (such as smart water IoT devices).

Innovative leak detection processes and methodologies – ensuring procedures leverage the power of new acoustic leak detection technologies and conducting prompt analysis of field data to reduce leak run-times and minimise leak impact on customer perceptions.

Leakage management software and data management – recognising the opportunity to collect other valuable data from throughout the water network (includes intelligence on broken assets, missing fittings, and customer theft). Our leak detection data management software portals are used daily by our customers to understand site works, NRW and status of repairs.

Engagement as a true partner – longer-term arrangements where we are an extension of your existing teams for leak detection and water loss management.

The purpose of trunk main leak detection is to find all the leaks that do not surface or come to the attention of the water utility on their large diameter trunk main network. The detection process involves teams of skilled leak detection technicians using advanced correlation devices. This may be in response to an increase in the minimum night flow (MNF) if the area is sectorised into a DMA or Water Supply Zone or simply as part of a proactive regular inspection schedule.

Many technologies for trunk main leakage detection utilise acoustic principles to identify and pinpoint leak locations. A pressurised water pipe will create a unique acoustic signature at the leak location due to the pressure differential between the inside and outside of the pipe—the water main acts as a medium for transmitting the acoustic signature of the water leak.

When water is escaping the pipe under pressure, it makes a distinct ‘hissing’ sound that can carry significant distances along the length of the water pipe and be detected on nearby service connections, hydrants or stop valves. Several factors influence the distance which the leak can travel but are primarily the pipeline material and diameter.

Aqua Analytics uses the most advanced leak noise correlator available to complete their trunk main leak detection work. This correlator is from the world’s leading leak detection equipment provider.

Trunk mains, typically assets that are over 300 mm in diameter, require a different approach to reticulation assets when it comes to leak detection. These are often assets critical to operations, and the current condition and presence of leaks must be well understood to reduce the likelihood of failure.

Trunk main correlators – specialised hydrophones or accelerometers are placed on the trunk main (typically at 1-2 km spacings), listening for specific frequencies and applying traditional correlation equations to detect the presence of leaks.

Trunk main leak detection is challenging due to the reduced sound propagation in larger diameter pipelines. Many utilities avoid trunk main leak detection activities due to a perceived lack of leakage on these assets; however, many examples in Australia and New Zealand prove this is inaccurate. Aqua Analytics can deliver trunk main leak detection using the following solutions:

Free-swimming leak detection technologies – a cylindrical device is inserted into a live pipeline, propelled by the water flow, and is captured downstream. The captured data is downloaded, analysed, and the leak location is determined.

Tethered leak detection technologies – a device is inserted into a live pipeline, attached to a long cable, and propelled by the water flow. An operator will listen for the acoustic signal from the device hydrophone and determine if any leaks are present.

Real-time trunk main monitoring – specialised hydrophone devices can monitor large diameter pipelines in real-time for changes in operating conditions that may indicate a new, developing or growing leak.

The Aqua Analytics team consists of internationally renowned experts on water leakage reduction, non-revenue water (NRW), and acoustic leak detection methodologies. Over several decades, we have developed customised water loss reduction strategies for conditions in Australia and New Zealand to ensure we achieve lower levels of water loss. We are viewed as leaders in trunk main leakage detection through our long-term engagements on projects in Sydney, Melbourne, Adelaide, Brisbane and throughout New Zealand.

We also pride ourselves on delivering excellent customer service and finding solutions to problems where others cannot. If you are looking to achieve results from your active leak detection project,  please contact us today by giving us a call, or through the enquiry form below.

Get in touch with Aqua Analytics

With offices across the region, we are well placed to promptly assist you. We try to respond to enquiries during the same business day.

Need help with your water network?

Aqua Analytics supports utilities with operational success in the areas of water loss management, active leakage control and all aspects of technology-driven smart water projects. Let us help you with our expertise in active leak detection.

Contact Us

Trusted by leading water utilities.

For over two decades, our team has been trusted by the regions leading water utilities to deliver results.

Aqua Analytics were easy to communicate with, very responsive and delivered the project with an outstanding level of professionalism. Great company, would use again!

The Aqua Analytics’ team was able to quickly mobilise and assist us with our water loss problem. They found a major leak which immediately reduced our baseline.

Aqua Analytics has seamlessly delivered our project since we have a single contact for pressure transient device procurement, installation and ongoing device maintenance.

Latest Updates

Read our latest news and blog posts on all things relating to smart water technologies, water loss management and water network solutions.

Pressure Transients in Water Networks

  • January 14, 2022
Pressure Transients Explained Pressure transients or ‘water hammers’ are transient events that occur in water pipeline networks as a result of valve opening/closing and pump starting/stopping. Pressure transients can have a severe impact on network performance and efficiency with pipe...

Multi-Year Project with Yarra Valley Water Commences

  • February 4, 2022
Originally published on 29 October 2021 Several months ago, Yarra Valley Water, one of the largest water corporations in Australia, appointed Aqua Analytics as its consultant to deliver active leak detection services for the corporation’s water distribution area. Both organisations...

Drought and Water Loss Reduction Activities

  • February 4, 2022
The Current Situation Many parts of Australia, and specifically New South Wales, are currently experiencing severe drought conditions. Next week, on 10 December, the Greater Sydney region will move to Level 2 Water Restrictions with dam levels falling to just...

Subscribe to our
regular newsletter.

Get regular updates about smart water solutions, case studies and upcoming events.