Water loss percentages can be useful, but they rarely tell the full story.
For Australian utilities, the Infrastructure Leakage Index (ILI) provides a more accurate benchmark for real losses and helps determine whether leakage is within a reasonable range.
In this article, you will learn:
By the end, you will have a clearer view of how to interpret ILI and what to do with it.
The Infrastructure Leakage Index (ILI) is a benchmark used to measure how efficiently a water network is controlling real losses. It compares the amount of water currently being lost through leaks with the level of leakage that would still exist in a well-managed network of that size and type.
In simple terms, ILI helps answer this question: how much leakage is occurring beyond what is realistically unavoidable?
That makes it more useful than looking at water loss as a percentage alone. A percentage can be misleading because it does not account for factors like network length, number of connections, or operating pressure. Two utilities may report similar water loss percentages while performing very differently in practice.
ILI focuses specifically on physical leakage from pipes, fittings, service connections, and storage assets. It does not measure non-physical losses such as metering errors, billing issues, or unauthorised use.
For Australian utilities, ILI is a practical benchmarking tool. It helps teams understand whether leakage performance is broadly under control or whether closer investigation, targeted intervention, or better data is needed.
Water loss is often reported as a percentage, but that figure on its own can hide more than it reveals. A network losing 8% of supplied water may appear to be performing well, while another losing 12% may appear inefficient. In practice, those numbers do not account for differences in network size, connection density, operating pressure, or system layout.
That is the problem with percentage-based reporting. It treats very different networks as if they operate under the same conditions.
ILI gives utilities a more meaningful benchmark because it focuses on real losses in context. Instead of asking what share of water is being lost, it asks whether the level of leakage is high or low relative to what would be expected in that specific network.
For Australian utilities, that makes ILI far more useful for performance assessment. It supports better comparison across systems, helps avoid misleading conclusions, and gives decision-makers a clearer view of whether leakage is within a reasonable range or needs action.
ILI is calculated by dividing Current Annual Real Losses (CARL) by Unavoidable Annual Real Losses (UARL).
Put simply, it compares the leakage a utility is experiencing now with the lowest level of real loss that would still be expected in a well-managed system. If the result is close to 1, the network is operating near its unavoidable level of leakage. A higher result suggests there is more recoverable loss in the system.
The formula itself is straightforward. The harder part is producing reliable inputs. To calculate ILI properly, utilities need accurate data on real losses, network length, number of service connections, average pressure, and other core system characteristics. That is why strong water balance calculations are such an important starting point.
That is why data quality matters so much. If the underlying leakage, asset, or pressure data is incomplete or inaccurate, the final ILI figure can point teams in the wrong direction. Used with good data, ILI becomes a practical benchmark rather than just another reported number.
ILI is useful, but it only becomes meaningful when read in context. There is no single score that tells every Australian utility whether leakage performance is good or bad. A regional network, a dense metro system, and a mixed network with older assets may all produce very different results for valid reasons.
That is why ILI should be used as a benchmarking tool, not a standalone verdict. It is most useful when utilities compare performance over time, across pressure zones or DMAs, and against similar network types rather than treating one number as the full story.
For Australian utilities, the real value of ILI is in what it helps reveal. A rising ILI may point to growing leakage pressure, deteriorating assets, slower response times, or hidden losses that are not being picked up early. A stable or improving ILI can show that leakage programs, repairs, or pressure management strategies are working. The number matters, but the trend and the network conditions behind it matter more.
ILI is a useful benchmark, but it does not explain the cause of leakage on its own. It can show that real losses are higher than they should be, but it cannot tell you whether the issue is driven by pressure, hidden leaks, recurring bursts, ageing assets, repair quality, or incomplete data.
That is why ILI works best as part of a broader leakage performance framework. It gives utilities a strong starting point for understanding whether the network is underperforming, then other data points help explain why.
Used well, ILI can support benchmarking, trend analysis, and prioritisation. Used on its own, it can oversimplify the problem. A utility may know its ILI is high, but still need pressure data, minimum night flow trends, burst history, or zone-level monitoring to decide what action to take next.
In other words, ILI is a strong indicator, not a full diagnosis.
A high ILI usually points to leakage that sits above what should be expected in a well-managed network. Common reasons include:
A high ILI does not tell you which of these issues is driving the result, but it does show that closer investigation is needed.
If ILI is trending higher than expected, the next step is not to react blindly. It is to work through the likely causes and confirm where action will have the biggest impact.
Start with the basics:
ILI is most useful when it leads to focused action. The goal is not just to report leakage performance, but to identify what is driving it and where intervention will deliver the best return.
ILI is only as reliable as the data behind it. If a utility is working with incomplete flow records, inaccurate pressure data, outdated asset information, or gaps in consumption reporting, the benchmark can become less useful and harder to trust.
That matters because ILI is often used to support real decisions. Utilities may rely on it to assess performance, prioritise leakage programs, justify investment, or report to leadership. If the inputs are weak, the result may point teams in the wrong direction or hide the areas that need attention most.
Good benchmarking depends on having consistent, connected, and up-to-date network data. That includes not just system-wide figures, but the supporting detail needed to understand what is happening across zones, assets, and operating conditions. Better pressure flow and logging can play an important role here.
For Australian utilities, better data does more than improve reporting accuracy. It improves confidence. Teams can benchmark leakage performance more clearly, identify issues earlier, and make decisions based on evidence rather than assumptions.
Better leakage benchmarking does more than improve reporting. It helps utilities make clearer, more targeted decisions across operations, planning, and investment.
When ILI is backed by reliable network data, teams can see whether leakage is stable, improving, or drifting away from expected performance. That makes it easier to prioritise pressure management, leak detection, repairs, and renewals based on actual need rather than assumptions.
It also gives decision-makers a stronger basis for investment. Instead of relying on broad system averages, utilities can link leakage performance to specific zones, assets, or operating conditions. That leads to more focused programs and a better return on both operational and capital spend.
For Australian utilities, this is where benchmarking becomes genuinely valuable. The goal is not just to know the number. It is to use that insight to reduce avoidable loss, support long-term planning, and make smarter decisions across the network.
ILI is useful because it shows whether leakage performance is where it should be. What it does not do is tell utilities where losses are occurring, which assets or zones are contributing most, or what action should come first.
That is why benchmarking only becomes valuable when it is connected to broader network insight. When utilities combine leakage metrics with stronger visibility across pressure, flow, asset condition, and zone-level performance, they can move beyond broad reporting and start identifying the factors driving avoidable loss.
For Australian utilities, that means more than simply knowing performance is off track. It means having a clearer basis for prioritising investigations, targeting investment, and supporting better operational and planning decisions across the network.
Most utilities already have data. The challenge is turning that data into clear, practical direction.
A high ILI can show that leakage performance is off track, but it does not show where to focus first, what is driving the result, or how to respond in a way that delivers measurable improvement.
Aqua Analytics helps utilities close that gap. We support the full process, from water balance and NRW analysis through to DMA monitoring, pressure and flow insights, leak detection, and ongoing network visibility.
A key part of this is AquaNRW, our water loss software designed to help utilities, councils, and asset owners track ILI, minimum night flow, and leakage volume, while using DMA pressure data and a unified view of network inputs to highlight areas that need attention.
For utilities under pressure to reduce losses, justify spend, and make the most of limited resources, that matters.
Better visibility means faster decisions, stronger field prioritisation, and more confidence when planning operational or capital responses.
We help turn leakage metrics into action, so teams can focus effort where it will have the greatest impact.
If your utility needs a clearer view of leakage performance and the data behind it, contact us today to discuss how we can support smarter benchmarking and more targeted network action.
When wet weather hits, does your sewer network spike beyond design limits?
If pump stations strain, treatment volumes surge, or capital upgrades keep creeping forward, infiltration inflow may be the hidden driver.
The challenge is not knowing it exists. The challenge is quantifying it and deciding what to do next.
In this guide, we break down how to investigate, prioritise, and reduce Infiltration inflow using structured monitoring, targeted inspection, and data-driven decision frameworks.
Infiltration and inflow (I&I) is the unwanted entry of water into a sewer network. This water is not wastewater from homes or industry. It is groundwater or stormwater that should not be in the sewer system.
Understanding inflow and infiltration in a sewer system is critical because it directly affects capacity, operating cost, and environmental risk.
Although often grouped together, inflow and infiltration occur through different pathways.
| Type | Source | How It Enters the Sewer | Typical Flow Pattern |
| Inflow | Stormwater | Direct connections, roof drains, illegal plumbing, open or damaged manholes | Rapid response during rainfall |
| Infiltration | Groundwater | Cracked pipes, defective joints, porous materials | Slower, sustained base flow increase |
Inflow is usually visible during or immediately after rainfall. It enters quickly and can cause sharp spikes in flow.
Infiltration is typically more persistent. It increases baseline flows and can remain elevated long after rainfall has stopped, especially in areas with high groundwater levels.
Both contribute to wet weather sewer flow, but their behaviour and solutions differ.
In practice, infiltration inflow is not identified by visual inspection alone. It is revealed through flow and rainfall analysis.
Common indicators include:
For example, a catchment may show a stable dry weather flow of 20 litres per second. After moderate rainfall, the same catchment peaks at 60 litres per second. If this increase cannot be explained by customer demand, infiltration inflow is likely contributing.
Excess water in a sewer system creates operational and financial pressure.
Key impacts include:
In many networks, I&I is not evenly distributed. A small number of sub-catchments often drive a large share of wet-weather peaks. This makes investigation and prioritisation essential.
It is common to assume that fixing pipes will automatically solve the issue. In reality, inflow and infiltration in a sewer system must first be measured and understood.
Without quantification:
A structured investigation provides clarity. It separates normal demand from rainfall response and identifies where the largest hydraulic gains can be achieved.
That investigation step is where meaningful reduction begins.
Most utilities know infiltration inflow is present in their sewer system. The challenge is understanding where it occurs, how much it contributes, and what action will deliver measurable improvement.
Investigation is the step that turns suspicion into evidence.
Reactive repairs often focus on visible defects or recent overflow locations. This approach can reduce local risk, but it rarely addresses the largest hydraulic drivers.
A structured investigation answers critical questions:
Without this clarity, investment decisions rely on assumptions.
When investigation is limited or absent, networks often face two common outcomes.
Both scenarios increase cost without proportionate benefit.
In each case, the underlying issue is the same. Decisions are being made without a clear, quantified understanding of how much unwanted water is entering the system and where it is coming from.
That understanding starts with a defined baseline.
The first objective of any inflow and infiltration reduction program is to quantify current network performance.
A baseline separates true wastewater demand from rainfall-derived flow. It defines how much of the peak load is driven by unwanted water rather than customer use.
This typically includes:
This quantified starting point becomes the reference for prioritisation and future verification.
If a catchment shows that 40% of peak wet weather flow is rainfall-derived, planners now know that a substantial portion of peak demand is potentially removable. That figure can be tested in hydraulic models to assess how reduction would influence required system capacity.
Infiltration inflow creates uncertainty because it inflates peak flows. Without separating real demand from unwanted water, planners must design for the highest observed peaks.
Quantification changes this.
By isolating rainfall response and base infiltration, the investigation allows planners to:
This shifts capital planning from assumption-based to evidence-based.
For utilities managing growth, compliance risk, or aging assets, reducing uncertainty in peak flow assumptions can materially influence upgrade timing and investment scale.
I&I is rarely uniform across a network.
A structured assessment typically reveals:
This allows utilities to focus resources where the return on intervention is highest.
Instead of spreading the budget thinly across the network, the investigation concentrates effort where it delivers measurable hydraulic benefit.
An inflow and infiltration reduction program is only as strong as its diagnostic phase.
Investigation:
Without this foundation, reduction efforts lack direction and proof.
With it, utilities gain a clear pathway from data to action.
Once a baseline has been established, the next step is identifying where and why infiltration inflow is entering the sewer system.
Effective investigation does not rely on a single tool. It combines monitoring, inspection, and analytics to move from broad catchment trends to specific assets.
The goal is simple. Isolate the highest hydraulic contributors and define the most efficient path to reduction.
Network flow monitoring is the foundation of most I&I investigation programs.
Temporary or permanent flow meters are installed at key points in the network, often at sub-catchment boundaries. Rainfall data is collected alongside flow data.
This allows teams to:
For example, if two catchments serve similar populations but one shows a 2.5 times wet weather peaking factor while the other peaks at 1.4 times, the first becomes a priority investigation area.
Flow monitoring narrows the search area before detailed inspection begins.
Rainfall response analysis interprets how quickly and how strongly a catchment reacts to rain events.
A rapid spike during rainfall typically suggests inflow, while a slower, sustained rise may indicate groundwater infiltration.
By analysing hydrographs across multiple events, utilities can:
This analysis links data to hydraulic behaviour. It explains not just how much flow increases, but why.
Once priority sub-catchments are identified, physical inspection begins.
Closed-circuit television inspections assess pipe condition, joint integrity, and structural defects. Manholes are also inspected for cracks, open pick holes, or frame and cover issues.
However, the condition alone does not equal hydraulic impact.
A pipe may show visible defects but contribute little to infiltration. Conversely, a small but poorly sealed joint in a high groundwater area may contribute significantly.
This is why CCTV should follow data-driven prioritisation, not replace it.
Smoke testing is used to identify direct inflow sources such as:
Dye testing can confirm specific pathways.
These methods are particularly effective in identifying rapid rainfall response contributors.
They are most efficient when deployed in catchments already identified through flow monitoring.
Persistent elevation in dry weather flow often signals infiltration.
Groundwater level monitoring and seasonal flow analysis help determine whether infiltration is:
This informs whether structural rehabilitation is likely to deliver a measurable reduction.
The final and often most critical layer is integration.
Flow data, rainfall records, inspection results, and asset condition are analysed together to rank sub-catchments.
Prioritisation frameworks often consider:
This creates a targeted intervention list rather than a network-wide repair program.
In many systems, a small proportion of assets or sub-catchments drives a large share of peak inflow and infiltration. Analytics helps reveal that concentration.
Investigation identifies where infiltration inflow occurs and how it behaves. A reduction program converts that insight into structured action.
Without a clear link between diagnosis and delivery, investigation remains academic. The value comes from turning quantified findings into prioritised interventions.
Before works begin, the baseline must be locked in.
This includes:
This baseline becomes the benchmark against which the reduction will be measured.
Investigation results should produce a ranked list of sub-catchments or assets.
Prioritisation typically considers:
This step ensures that investment focuses on locations where hydraulic return is highest.
In most networks, a small proportion of the system drives the majority of wet weather peaks. Targeting these areas first maximises impact.
Intervention type depends on the dominant source identified during the investigation.
Common reduction measures include:
The key principle is alignment. The intervention must address the identified mechanism.
If the rainfall response is rapid and direct, inflow control may deliver the greatest reduction.
If baseline flows remain elevated year-round, structural infiltration repair may be more effective.
This avoids broad rehabilitation programs that lack measurable hydraulic benefit.
Reduction programs are rarely delivered as a single project.
Instead, they are staged:
This iterative structure reduces risk and improves learning across the program lifecycle.
It also supports more accurate forecasting of network-wide reduction potential.
The ultimate objective is not just repair. It is system optimisation.
Once the reduction potential is quantified and validated, utilities can:
If measurable peak reduction is achieved, infrastructure expansion may be deferred or resized.
This is where investigation transitions into strategic value.
An inflow and infiltration reduction program is only credible if its results can be measured.
Without verification, reduction remains an assumption. With verification, it becomes a defensible performance improvement.
Measurement closes the loop between investigation, intervention, and planning.
Post-works monitoring should mirror the original investigation set-up wherever possible.
This includes:
Consistency is critical. The same methodology used to define the problem should be used to confirm the outcome.
Verification typically focuses on changes in:
For example, if a catchment previously peaked at 60 litres per second during moderate rainfall and now peaks at 45 litres per second under similar conditions, the reduction is measurable.
Hydrograph comparison provides clear visual confirmation of improvement.
One storm does not define performance.
Reduction should be validated across multiple rainfall events and, where possible, across different seasons.
This helps confirm:
This step strengthens confidence in the results.
Measured flow reduction must then be translated into planning outcomes.
This may include:
When reduction is expressed in terms of capacity headroom or deferred capital expenditure, its value becomes clear to executives and regulators.
Once reduction has been verified in initial catchments, the same investigation and intervention framework can be applied elsewhere.
This creates:
Over time, the program shifts from isolated repairs to systematic performance management.
Inflow and infiltration in a sewer system is not just a maintenance issue. It is a capacity, cost, and risk issue.
The path forward is structured:
This approach replaces assumption with evidence and reaction with strategy.
For utilities seeking to manage wet weather performance, defer unnecessary capital works, and improve system resilience, investigation-led reduction provides a clear pathway.
Many utilities recognise inflow and infiltration in their sewer system. Fewer have a structured, defensible pathway to quantify it and act with confidence.
Aqua Analytics helps bridge that gap.
We work with utilities and councils to isolate rainfall-derived inflow, quantify base infiltration, and identify the sub-catchments that drive peak wet weather performance.
Our team integrates flow monitoring, rainfall analysis, asset condition data, and network analytics into a clear prioritisation framework. This allows you to focus investment where it delivers measurable hydraulic benefit.
Our assessments support:
We do not rely on assumption or broad rehabilitation programs. We focus on evidence, prioritisation, and measurable impact.
If you need clarity on how infiltration inflow is affecting your network, or want to understand where reduction can deliver the greatest return, speak with our team about a targeted assessment.
We can help you move from uncertainty to quantified action.
Aqua Analytics, a leading provider of water network management services across Australia and New Zealand, today announced its strategic expansion into Western Australia following the acquisition of the water loss field operations of Engineered Efficiency, a respected regional specialist in water loss reduction.
This expansion enhances Aqua Analytics’ national footprint and strengthens its ability to support clients in WA with local, on-the-ground resources.
“Western Australia is a key market, and this expansion allows us to support our clients more effectively with a local presence,” said Hugh Chapman, Managing Director of Aqua Analytics.
“This move complements our organic growth and brings a proven, experienced team into our business, ensuring we can deliver our full suite of services with greater efficiency and responsiveness across the country.”
The acquired division has a long-standing reputation for delivering quality services for major utilities and mining companies, including Water Corporation and Busselton Water.
New Zealand’s water sector is at a turning point. In too many communities, ageing drinking water, wastewater and stormwater systems are struggling – leading to leaks, pollution, and hefty repair bills for ratepayers.
Recognising these challenges, the government has introduced “Local Water Done Well”, a comprehensive reform initiative to upgrade infrastructure, improve service quality, and secure sustainable water management for the future.
This blog post provides an overview of the Local Water Done Well reform and its significance, and explores how councils and water utilities can tackle ageing networks and non-revenue water (NRW) losses. We’ll discuss how to operationalise the new legislation at a tactical level for measurable improvements, innovative financing and contracting models (like performance-based NRW reduction contracts), and highlight successful case studies from abroad. By the end, it will be clear how this reform can drive positive change – and how specialists like Aqua Analytics are ready to assist New Zealand’s councils and utilities in making water services truly “done well.”
New Zealand’s water infrastructure has suffered from decades of underinvestment, leaving a legacy of ageing pipes and treatment plants due for renewal. Industry estimates suggest the country needs to invest on the order of NZ$120–185 billion over the next 30 years to upgrade and expand water systems. Much of the network was laid mid-20th century or earlier, and some pipes in use are over 100 years old. As pipes reach the end of their life, failures become more frequent – water mains burst, sewers overflow, and service interruptions and leakage levels rise.
In Wellington, for example, the water utility reported that its pipes are “ageing at a faster rate than we can replace them,” with numerous mains in the capital region now over a century old. The result has been a rash of pipe bursts and leaks: at one point in early 2024, Wellington Water was dealing with over 3,000 leaks, a situation that demanded urgent intervention and funding to bring under control.
Ageing three waters infrastructure (drinking water, wastewater, and stormwater) doesn’t just inconvenience residents – it carries serious public health and environmental risks. In recent years, thousands of Kiwis have been issued boil-water notices or fallen ill due to substandard drinking water, and communities have endured sewage on streets and unswimmable beaches when sewer or stormwater systems fail. These issues underscore why reform is needed. As the National Party’s water policy described, the status quo of failing systems has led to “pollution, wastage and massive bills for ratepayers”.
Simply put, many local councils on their own have struggled to fund and manage the necessary upkeep of their water networks under the old model.
Local Water Done Well emerged as a response to these mounting challenges – aiming to chart a new course that fixes ageing infrastructure while keeping water services under local control. The previous government’s Three Waters Reform (which was later rebranded “Affordable Water”) had proposed shifting assets from councils to four large entities, but it faced public backlash and was repealed in early 2024. In its place, the current government’s Local Water Done Well programme seeks to “address Aotearoa New Zealand’s long-standing water infrastructure challenges” and restore confidence that safe, reliable water services will be delivered. Crucially, it strives to do this without stripping local ownership.
Local Water Done Well not only keeps water in local ownership and control but also provides a pathway for significant infrastructure upgrades.
Councils retain ultimate responsibility for water service delivery under Local Water Done Well – but with stronger direction, new funding tools, and clear performance standards to ensure we don’t simply revert to the old ways that weren’t working.
Local Water Done Well is the central government’s plan to reform how drinking water, wastewater and stormwater services are delivered across New Zealand. Announced in December 2023, it replaces the prior Three Waters reform programme while aiming to achieve similar outcomes in terms of safe drinking water, environmental protection, and sustainable infrastructure.
The significance of this initiative lies in balancing local control with nationwide standards and support. Under the programme, water assets remain owned by local councils (avoiding the controversial “mega-entities”), but councils are now required to meet stricter water quality rules, invest adequately in infrastructure, and operate under greater regulatory oversight.
In short, Local Water Done Well provides a new framework where local ownership is preserved, yet accountability and investment are ramped up to ensure communities get the quality water services they need.
The reform is being implemented in three stages, each with its own legislation:
The significance of Local Water Done Well is that it creates a pathway to environmental and financial sustainability for quality water services across New Zealand. It addresses the core problems of the old model by ensuring dedicated funding (through ring-fencing and improved financing options), stronger oversight (through regulators and potential government intervention if needed), and encouraging scale and collaboration (via regional service delivery models) – all while keeping water assets in public hands.
For council water managers, engineers, and policymakers, this reform is a call to action to up their game: to thoroughly understand the condition of their networks, plan upgrades strategically, reduce water loss, and embrace new models that can deliver better outcomes for communities.
One of the immediate challenges councils face under the new regime is how to tackle ageing water networks with limited resources. With so much infrastructure approaching or past its design life, a critical question is: which pipes, plants or pumps do we fix first?
This is where asset condition assessment and asset management come to the forefront. The Local Water Done Well framework, through the required Water Services Delivery Plans, compels councils to take stock of their assets and provide an assessment of their water infrastructure – how much they need to invest and how they plan to finance and deliver it. In other words, councils must move from reactive patch-ups to proactive, data-driven asset management.
Conducting systematic condition assessments of water supply pipelines, sewer lines, and related facilities allows councils to identify which assets are most deteriorated or high-risk. For example, utilities can grade the state of their underground assets by using tools like CCTV inspections, acoustic leak detection, and pipeline condition assessment techniques.
By knowing where the worst leaks or weakest pipes are, councils can prioritise renewals and repairs that yield the most significant benefit – preventing an imminent water main burst or reducing substantial leakage. Prioritisation is essential given budget constraints; it ensures that every dollar invested goes to the highest-need projects first, delaying the replacement of assets that are still in acceptable condition and focusing on the ones at risk of failure.
New Zealand’s recent experience underscores the importance of this approach. In Wellington, years of underinvestment led to a large backlog of leaking pipes, and it became clear the utility couldn’t replace everything at once. Wellington Water developed a straightforward prioritisation process to ensure repair crews focus on the most significant leaks – those losing tens of litres a minute or posing a risk to supply – while lower-priority drips are deferred until resources allow. This triage approach, guided by data on leak flow rates and pipe criticality, is a tactical form of condition-based prioritisation in its most simple form. It has paid off: by mid-2024, with increased council funding and an accelerated leak repair schedule, Wellington had reduced its annual water loss slightly (from an estimated 44% down to 41% of supply) and cut the number of open leaks by 57% over eight months. While there is still a long way to go, this progress shows how focusing effort on the worst parts of the network first can start to turn the tide on an ageing system.
Across the country, many councils must undertake similar asset condition reviews as part of their Water Services Delivery Plans. These plans must include baseline information about water assets and operations, current performance, and projected capital investment needs. Essentially, each council (or collective of councils) has to present a roadmap for infrastructure renewal and maintenance that meets regulatory standards. Condition assessment is the foundation of that roadmap – you can’t plan to fix what you haven’t measured. By identifying pipes with the highest break frequencies or poorest condition based on advanced non-destructive technology, councils can schedule their renewal programs to prevent failures before they happen. This averts disruptive outages and public health incidents and is cost-effective in the long run. Fixing or replacing a pipe just before it fails (or before leakage gets out of control) is typically cheaper than emergency repairs after a burst and the consequential damage to roads or property.
In summary, the new water reform expects councils to know their assets intimately and plan upgrades wisely. For water engineers, this means ramping up asset condition assessment programs now if they haven’t already. Tools like asset management information systems, GIS mapping of break history, and advanced analytics (predictive modelling of pipe failure based on age/material) can all support this effort. A robust understanding of network condition will inform everything from renewal capital works scheduling to setting realistic budgets and tariffs. It also feeds directly into tackling one of the biggest issues highlighted by Local Water Done Well – New Zealand’s high levels of non-revenue water.
One startling symptom of New Zealand’s ageing water networks is the high rate of non-revenue water (NRW) – water that is produced and enters the distribution system but never reaches a paying customer. NRW includes physical losses (leaks and overflows) as well as commercial losses (water that is not billed due to metering inaccuracies or unauthorised use such as theft).
In many New Zealand towns and cities, a significant portion of treated drinking water simply goes missing. How significant? Research published in 2025 showed that New Zealand’s leakage levels average about 22% of water supplied, which is far worse than leading countries like the Netherlands (5% loss) or Germany (6%). In fact, when comparing an internationally recognised metric called the Infrastructure Leakage Index (ILI) – which benchmarks leak performance relative to system size – New Zealand ranked near the bottom among 15 OECD countries, with a median ILI of 2.7 compared to Denmark’s world-class 0.7.
These figures make clear that New Zealand has a major water loss problem by developed-world standards. Literally, tens of billions of litres of treated water are being wasted each year through leaky infrastructure or unmetered usage – water that costs money to treat and pump but yields no revenue.
The consequences of high NRW are multi-faceted. Economically, it’s estimated around $122 million per year is essentially poured down the drain due to the volume of water lost in our systems. Environmentally, that’s wasted water that could have been conserved and extra strain on water sources, especially during dry summers.
Operationally, high leakage can reduce network pressure and firefighting capability and is often a sign of weak spots that could erupt into bigger main breaks. Moreover, if a fifth (or more) of the water supply is non-revenue, it means customers are ultimately paying higher rates to cover the inefficiency – or maintenance is underfunded because a lot of production isn’t billed.
Reducing non-revenue water is, therefore, a key priority for improving both the financial and environmental sustainability of water services. The Local Water Done Well initiative brings NRW into focus by calling for sustainable infrastructure management and benchmarking against best practices.
Encouragingly, some progress is already being made. The recent Public Health Communication Centre briefing notes that places like Wellington have begun to get a handle on their leaks and that nearly 75% of New Zealanders support the use of water metering – a tool that can greatly aid in detecting private-side leaks and managing consumption. Universal metering is one strategy many councils may need to consider: as Wellington Water acknowledged, “we cannot accurately track current water loss without universal metering”.
Many districts historically have had flat-rate water charges or no meters for residential connections; introducing meters not only promotes fairness and conservation but helps pinpoint leaks (for example, a spike in night-time usage at a metered property can indicate a hidden leak on the customer’s side).
Beyond metering, effective NRW reduction strategies include a combination of operational fixes and capital investments:
Notably, reducing NRW has compounding benefits. Every cubic meter of water saved through leak reduction is a cubic meter that doesn’t need to be produced – saving treatment chemicals and energy (and therefore carbon emissions) and freeing up capacity to support growth or resilience in droughts. It’s one of the most cost-effective “new” water supply sources.
In the context of Local Water Done Well, demonstrating progress on NRW will likely be an essential performance indicator for councils. High water loss could draw regulatory scrutiny in the future.
The bottom line for New Zealand’s water managers is that tackling NRW is no longer optional – it’s essential for financial viability and public trust. The good news is that with modern techniques and a focus from both central and local government, significant reductions are achievable, as our next section on case studies will illustrate.
“Local Water Done Well” represents a pivotal opportunity to put New Zealand’s water services on a path to long-term sustainability. This reform can deliver safer drinking water, healthier environments, and more resilient communities by addressing ageing infrastructure, mandating better asset management, reducing water loss, and enabling smarter financing. Crucially, it achieves this while keeping water assets in the hands of local councils – ensuring communities maintain a say, but with stronger support and oversight from central authorities to ensure water services are financially sustainable and meet modern standards.
The charge is clear for municipal water managers, engineers, and policymakers. Now is the time to assess your infrastructure, set ambitious yet attainable targets (for example, bring that 25% leakage down towards 10% over time, or renew that oldest 5% of your pipes), and use the new tools at your disposal. Develop your Water Services Delivery Plans not as a compliance tick-box, but as a strategic blueprint that will guide investment and operations for the next decade.
As the reform progresses, success will be measured in tangible outcomes: fewer boil-water notices, reduced sewage overflows, lower percentage of water lost, and ultimately public confidence that the system is improving.
The government has done its part by creating the framework and increasing funding avenues. The onus is on local bodies and their industry collaborators to deliver results. It’s a significant undertaking that comes with the benefit of global knowledge and modern technology to guide the way.
This is where Aqua Analytics is ready to help. With deep expertise in water network management, non-revenue water reduction, and data-driven decision support, Aqua Analytics is a valuable partner to large and small councils across New Zealand. Whether it’s implementing a district metering program for a metropolitan utility, conducting network-wide asset inspection prioritisation plans for a medium-sized district’s pipe network, or helping a small council set up a smart leak detection and pressure management regime – our team has the experience and tools to turn reform objectives into on-the-ground improvements.
Our approach is to empower local water authorities with the insights and technology they need to make informed decisions and demonstrate progress. In the spirit of Local Water Done Well, we collaborate closely with your staff – transferring knowledge, building local capacity, and ensuring solutions are tailored to your community’s needs.
The challenges of ageing infrastructure and water loss may seem daunting, but they are manageable with the right plan and partners. New Zealand is poised to leap forward in water service delivery – a transformation that will protect public health, support economic growth (through reliable services and housing development), and safeguard precious water resources for future generations. It’s an exciting time to be a water professional in Aotearoa, as we blend local solutions with global expertise to indeed do water “well.”
Councils and utilities should seize the momentum of the Local Water Done Well reforms to kickstart projects that have long been on the wish list – be it that critical pipeline renewal, a comprehensive leak detection sweep, or setting up a regional water consortium for shared strength. With supportive legislation, better financing, and proven strategies at hand, there are no excuses for delay. Let’s turn policy into performance.
Contact us to learn more about how we can assist your utility or council navigate these reforms and achieve tangible water savings and service improvements. The journey to a better water future is underway – let’s get it done, and done well.
Gippsland Water has appointed Aqua Analytics to deliver its first-ever structured leak detection program. This innovative initiative underscores Gippsland Water’s commitment to proactively tackling water loss and enhancing the efficiency of its network, setting a new benchmark for water management in the region.
The program will see Aqua Analytics leverage advanced acoustic technology alongside our expert teams to identify and address leaks throughout the water network. By targeting non-revenue water (NRW) loss, this partnership aims to secure multiple long-term benefits for the Gippsland community, including:
Gippsland Water Managing Director, Sarah Cumming, said the program would help minimise water losses and keep customer bills down.
“Water is a precious resource and we want to make sure we’re doing all we can to conserve it,” Ms Cumming said.
“This is the first time we’ve used this technology on a large scale, and we’re excited to see the results it will bring for our team and our customers. If it’s successful, we hope to use it in other parts of our service area too.
“Our team will fix any leaks we find from the meter back to the main and they’ll also endeavour to let customers know if we suspect there may be a water leak on their property.”
The project is scheduled for an initial term of two years, with an option to extend for an additional two years.
About Gippsland Water
Gippsland Water is a Victorian Government-owned retail water corporation serving over 68,800 customers across Gippsland, Australia. Dedicated to providing reliable water and sewerage services, Gippsland Water plays a vital role in supporting the community’s health, economy, and environment.
World Water Loss Day on 4 December 2025 highlights the critical global challenge of water loss in supply networks.
Created to raise awareness and promote meaningful action, the day underscores the scale of inefficiencies that lead to billions of litres of treated drinking water being wasted every day through leakage, unauthorised consumption, and unmetered use.
It also provides an essential platform for sharing emerging technologies, proven methodologies, and collaborative approaches that support more sustainable water management.
By improving network performance and reducing losses, utilities can strengthen service reliability, increase operational efficiency, and better protect scarce water resources.
At Aqua Analytics, we are proud to contribute to these efforts across Austraia and New Zealand. Our team delivers advanced water network solutions that help utilities identify inefficiencies, target leakage, and optimise long-term performance, thereby supporting a more resilient and sustainable future for communities across the region.
Water loss is a critical global issue, with far-reaching consequences for resources, communities, and the environment. According to a study by Liemberger and Wyatt (2019), the global volume of non-revenue water (NRW) — water lost through leaks, theft, or unmetered use — is estimated at 346 million cubic metres per day.
Essentially, for every 10 litres of water sent into the network, about 3 litres are wasted and never used. The economic cost of this lost water amounts to USD $39 billion annually.
The implications of this are significant. If just one-third of global NRW were saved, it would provide enough water to meet the daily needs of 800 million people. This highlights the immense potential for improvement in water supply systems.
Beyond economic losses, water wastage exacerbates challenges in regions already grappling with water scarcity. The growing emphasis on the connection between water loss and carbon emissions reflects heightened awareness and increased funding for water projects. World Water Loss Day shines a spotlight on all these issues, urging collective action to reduce waste and ensure sustainable access to water for all.
Get involved in World Water Loss Day by using #WorldWaterLossDay in your social media posts, or by posting on the IWA Water Loss Specialist Group LinkedIn Page.
Addressing water loss requires collective action from governments, utilities, communities and the private sector. Collaboration strengthens efforts, enabling more comprehensive and sustainable solutions to this global challenge. Here’s how collaborative action is the best way to combat water loss:
By combining the efforts of all stakeholders, we help create unified strategies that not only reduce water loss but also secure sustainable water supplies for future generations.
Reducing water loss is essential for protecting resources and ensuring efficient water supply. Here are some proven strategies that utilities and organisations can implement:
At Aqua Analytics, we specialise in water loss reduction and offer comprehensive NRW consulting services. Our team collaborates closely with clients to design effective strategies, leveraging cutting-edge technology and expert insights. By prioritising efficiency and precision, we help utilities minimise non-revenue water, lower operational costs, and promote sustainability.
World Water Loss Day is a timely reminder of the ongoing challenges posed by water loss and the need for coordinated action across the sector.
With close to one-third of treated drinking water lost globally through leakage and inefficiencies, the imperative for smarter approaches, genuine collaboration, and informed public engagement has never been greater.
Progress is achievable. By embracing advanced monitoring technologies, strengthening partnerships between utilities and industry, and supporting community awareness, meaningful reductions in water loss can be realised. These efforts not only drive more efficient use of valuable water resources but also safeguard the environment and improve the resilience of future water supplies.
This World Water Loss Day, we encourage all stakeholders — from utility practitioners and policymakers to local community members — to play an active role in supporting better water network performance. Every contribution, no matter how small, helps shape a more sustainable and secure water future.
To understand how Aqua Analytics can assist with reducing losses and improving the performance of your water network, we welcome you to get in touch.
Together, we can strengthen the reliability of our water systems and deliver lasting benefits for generations to come.
Aqua Analytics, a leading provider of water network intelligence solutions, today announced it has been awarded a two-year asset maintenance contract extension with Yarra Valley Water, one of Australia’s largest water corporations.
The extension follows three years of successful collaboration in proactive leak detection and associated services.
Under the extended agreement, Aqua Analytics will continue to deploy its expertise and leakage management technologies to minimise water loss across Yarra Valley Water’s vast distribution network, spanning 4,000 square kilometres and over 10,000 kilometres of water mains.
Using planned inspections and real-time network monitoring, Aqua Analytics will promptly identify and report leaks, facilitating swift repairs through Yarra Valley Water’s integrated asset management system.
“We are thrilled to deepen our partnership with Yarra Valley Water and contribute to their ongoing commitment to water sustainability,” said Hugh Chapman, Managing Director of Aqua Analytics.
“The positive outcomes of our initial collaboration underscore our shared mission to deliver reliable and sustainable water services to Yarra Valley Water’s customers”.
Aqua Analytics’ innovative approach to network leak detection includes the use of acoustic equipment, sensors and data analytics to optimise specialist field teams. This has significantly improved leak identification for Yarra Valley Water, benefiting the environment and the more than 2 million people who rely on their services daily.
Yarra Valley Water Acting General Manager Service Futures Raghu Bharadwaj said Aqua Analytics had consistently proven their commitment to securing water resources for future generations.
“We’re really excited to expand our partnership with Aqua Analytics, using their advanced AI data loggers to enhance our water management capabilities.”
“Their tailored approach not only optimises our operational efficiency, but also aligns perfectly with our customer commitment to deliver reliable and timely services, as outlined in our price submission.”
“By integrating Aqua Analytics’ technology into our infrastructure, we’re better equipped to proactively identify and resolve leaks quickly, ensuring better outcomes for our customers, the community, and environment,” Mr Bharadwaj said.
About Aqua Analytics
Aqua Analytics is a specialist water network intelligence provider dedicated to helping water utilities optimise their operations and reduce water loss. With offices throughout Australia and New Zealand, Aqua Analytics delivers water network management solutions and expert support to a growing client base across the region.
About Yarra Valley Water
Yarra Valley Water is one of Australia’s largest water utilities, with a service area covering 4,000 square kilometres. Every day, more than 2 million people and over 61,000 businesses rely on its water and sewerage services.
The corporation manages $6 billion worth of infrastructure, including a network of over 21,500 kilometres of water, recycled water and sewer mains. Yarra Valley Water’s purpose is to support the health and wellbeing of its customers and create a brighter future for communities and the natural environment.
Australia’s major telecommunications providers are shutting down their 3G networks throughout 2024. This has critical implications for water utilities and councils reliant on 3G-connected smart devices.
If your water infrastructure includes pressure loggers, PRV controllers, acoustic loggers, meter pulse loggers, or other remote monitoring systems, urgent action is needed. Aqua Analytics partners with water utilities and councils to seamlessly transition your connected water assets to the latest cellular protocols (Cat-M1, NB-IoT, and 5G).
The following legacy devices often rely on 3G and may be rendered obsolete if not upgraded:
We understand the water industry’s unique challenges. Our process is designed for minimal disruption:
Proactive action is crucial. Contact Aqua Analytics today for a free infrastructure assessment. We’ll help you navigate the 3G sunset and ensure your water utility stays ahead of the curve.
Airports are intricate hubs of activity, relying on a vast infrastructure network to facilitate smooth operations. Among the critical components of this infrastructure that are often forgotten about are buried water pipelines. These pipelines transport water for various purposes, such as drinking, fire suppression, irrigation, and industrial processes. Efficient management of these pipelines is paramount to ensuring uninterrupted water supply, reducing water loss, and achieving sustainability goals.
In this blog post, we’ll delve into the strategies and technologies that can help airports effectively manage their buried water pipelines.
Water plays a pivotal role in airports, and here’s why:
Buried water pipelines present specific challenges in an airport environment:
Properly managing buried water pipelines is crucial for airports to ensure reliable water supply while minimising costs and environmental impact. Here are some key strategies:
A water audit is the first step towards efficient water management. It involves a thorough assessment of:
Smart water network software empowers airports with real-time awareness of their water networks. This software can:
Acoustic loggers are valuable for proactive real-time leak detection, particularly during off-peak hours.
Regular pipeline condition assessments provide critical information about buried pipelines’ structural integrity and remaining lifespan.
Besides the strategies above, here are some additional practices airports can adopt:
Managing buried water pipelines within airport precincts requires a strategic and proactive approach. By incorporating the strategies outlined in this blog post – water audits, smart water infrastructure, leak detection technologies, condition assessments, and other best practices – airports can safeguard their water resources, improve operational efficiency, and embrace sustainability.
Contact us today for a free consultation on how Aqua Analytics can help you manage your buried assets throughout your airport precinct.
Aqua Analytics, a company dedicated to helping water utilities reduce non-revenue water and manage leakage, is celebrating a successful year with a unique twist: Leak Lager.
This limited edition brew, crafted using water identified as leakage by Aqua’s skilled teams, serves as a toast to the impressive 11 billion litres saved and 3,500 leaks plugged by Aqua in 2023 across Australia and New Zealand.
Beyond being a celebratory drink, Leak Lager is a conversation starter.
Each can sent to clients and suppliers is a tangible reminder of the power of sustainability, innovation, and unconventional thinking. It highlights the positive impact that can be achieved through collaboration and commitment to solving critical water challenges.
“Leak Lager is more than just a beer,” says Chris Medcalf, Operations Manager at Aqua Analytics. “It is a toast to our achievements, but also a challenge to ourselves and the industry to push even further and ensure a sustainable water future for all.”
Aqua Analytics’ mission to reduce water network leakage across Australia and New Zealand goes beyond Leak Lager.
The company utilises best-in-class methodologies and expertise to help water utilities pinpoint and fix leaks, saving millions of litres of water each year. This not only benefits the environment but also reduces utilities’ costs and assists in the drive towards net zero carbon emissions.
