Water utilities across Australia and New Zealand are facing a familiar challenge: how to see what’s really happening inside complex, interconnected distribution networks without costly isolation or large-scale capital works.

Traditional District Metered Areas (DMAs) have long been the backbone of non-revenue water (NRW) management, but they come with limitations. Enter Virtual District Metered Areas (vDMAs), the next evolution in intelligent water-loss management, driven by data, analytics and intelligent water loss software such as AquaNRW.

This article explores how vDMAs work, why utilities are rapidly adopting them, and how AquaNRW is helping bring this technology to life across real water networks.

What is a District Metered Area (DMA)?

Traditionally, a District Metered Area (DMA) is a hydraulically isolated zone within a water-distribution network where flow (and sometimes boundary pressures) are monitored. By dividing the network into manageable segments, a utility can perform water balances, monitor minimum night flow (MNF), locate leak sources and manage supply reliability. 

The benefits of a well-designed DMA include:

  • Improved leak detection and localisation
  • More accurate assessment of non-revenue water (NRW) by zone
  • Better pressure management and risk control
  • Enabling utilities to prioritise field works and capital renewal

However, conventional DMAs come with constraints: high capital cost, significant network interruption to install boundary valves/flow meters, potential supply reliability issues and water quality concerns in isolated segments.

Transitioning to Virtual DMAs (vDMAs)

A virtual DMA (vDMA) replicates the segmentation benefits of a physical DMA but uses data and analytics rather than strictly hydraulic boundaries. In essence, vDMAs leverage strategically placed sensors (flow and/or pressure), network analytics, and software to create “zones” for monitoring losses without fully isolating the network.

Why vDMAs are compelling:

  • Lower disruption: you don’t necessarily have to install a maze of boundary valves or isolate parts of the network.
  • Flexibility: zones can be re-defined, aggregated or refined as data emerges.
  • Better integration: real-time flow/pressure data feeds analytics, enabling earlier detection of anomalies.
  • Suitable for complex, interconnected systems where traditional DMA segmentation is challenging.

Ultimately, Virtual DMAs offer greater flexibility in establishing measurement areas across the water distribution system. 

How vDMAs support water-loss / NRW reduction

The core of NRW management is understanding where water is disappearing. With vDMAs, you can:

  • Perform zone-level water balance: inflow minus authorised consumption gives losses per vDMA.
  • Monitor MNF (Minimum Night Flow) for each zone: elevations in night flows often point to background leakage or hidden bursts, and with the continuing deployment of smart meters, enabling water utilities to move towards a “smart DMA”.
  • Identify subtle pressure fluctuations across the water network via live sensors, which helps understand and localise potential areas of leakage.
  • Prioritise field interventions based on data flagged by the analytics platform: you allocate crews where the potential water savings are highest.
  • Measure and report leakage indicators for each zone (e.g., m³/day, litres/connection/day, Infrastructure Leakage Index (ILI) by zone), and then evaluate the impact of interventions.

In short: vDMAs turn large, complex water networks into monitored, actionable segments, enabling more intelligent decisions and more cost-effective leakage control.

Integrating vDMAs with AquaNRW

At Aqua Analytics, our AquaNRW water loss software is specifically designed to enable and scale vDMA strategies for utilities and councils. Here’s how it fits:

  • Data ingestion & aggregation: AquaNRW pulls in flow-meter and pressure-logger data from across the network, including bidirectional insertion meters, pressure loggers and other IoT sensors.
  • Zone definition and virtual segmentation: Utilities can create virtual zones (vDMAs) within the system, aggregating meters/pressure points into logical groupings rather than rigid hydraulics.
  • Analytics & AI event-detection: AquaNRW embeds analytics (including AI/ML techniques) to automatically flag unusual events (sudden night-flow jumps, abnormal pressure variations, potential burst/leak conditions).
  • Dashboard & reporting: The platform provides a clear visual of MNF trends, water balance by virtual zone, leakage volumes, zone ranking by loss potential, and alert status for field crews.
  • Operational integration: The system connects analytics to field task management — enabling the field team to receive actionable leads, schedule investigations, and close the loop on interventions.
  • Scalable & cost-effective: This approach means even regional utilities or councils with limited budgets can progress from very coarse network monitoring towards a refined vDMA-based leakage programme.

Case Study: Large Utility with Complex Interconnected System

Here’s a real-world example (anonymised) of how we helped a large distribution utility overcome the limitations of traditional segmentation.

Background: A major utility with many thousands of kilometres of mains. Their networks are often split into large distribution zones with a single flow meter located at a key reservoir outlet. The system is very interconnected, making physical DMA segmentation difficult and expensive. While the single meter provided an overall picture of total system input, it lacked the granularity needed to detect and prioritise leakage zones.

Our intervention:

  • Conducted a desktop network review: analysed pipe layout, customer zones, historical flows, pressures and existing metering to identify logical segmentation for virtual zones.
  • Designed 5 vDMAs (virtual zones) within the network, sized and defined based on hydraulic connectivity, customer load patterns, pressure zones and practical metering points.
  • Installed 6 bidirectional insertion flow meters at the key inflows/outflows of the five vDMAs, plus 10 pressure loggers distributed across the zones to capture pressure fluctuations, transients and baseline conditions.
  • Integrated all the data into AquaNRW, configured the zones, defined alert thresholds (night-flow thresholds, pressure anomaly bands) and enabled AI-based event detection.
  • Launched the monitoring phase. The platform automatically flagged elevated MNF in vDMA 3, pressure transients in vDMA 1 and burst indicators in vDMA 5. Field crews were directed accordingly.

Outcomes:

  • Within weeks, the utility identified and repaired a hidden burst in zone vDMA 5, resulting in a leakage volume equivalent to several megalitres per annum.
  • The MNF for vDMA 3 dropped by ~12 % after targeted intervention, improving the water balance for that zone.
  • The utility now has visibility on each of the five zones: inflows, authorised consumption, leak-volume estimates, alert status and trending metrics.
    Because the network remained online and supply reliability was unaffected (thanks to the virtual rather than physical segmentation), the project delivered a strong business case for rollout across further zones.

Best-practice steps to implement vDMAs (and how AquaNRW supports each)

Here is a recommended implementation framework that regional councils and water utilities can use to guide their journey from coarse monitoring to refined vDMA-based leakage control:

  1. Baseline analytics & network segmentation
  • Review historical flows, pressures, mains layout and customer distribution.
  • Identify logical zones for vDMA segmentation based on hydraulic connectivity, typical flows, supply points and priority areas.

AquaNRW helps ingest existing data and supports zone modelling.

  1. Sensor deployment & data integration
  • Install bidirectional flow meters at key zone inflows/outflows.
    Deploy pressure loggers at strategic points within zones.
  • Ensure communications infrastructure (IoT, SCADA, telemetry) is integrated.

AquaNRW ingests these real-time feeds, displays status and checks data integrity.

  1. Define virtual zone boundaries & thresholds
  • Within the software, define each zone (vDMA), associate the sensors, set minimum night flow (MNF) thresholds and pressure anomaly bands.
  • Configure alerts for deviations.

AquaNRW’s zone-management module supports this and tracks parameters automatically.

  1. Real-time monitoring & alerting
  • Run weekly and nightly checks on MNF, inflow vs consumption, pressure behaviour.
  • Use AI/analytics to flag abnormal behaviour: spikes in night flow, sustained pressure drop/drop, burst-type signatures.
  • Field teams receive actionable leads via the platform.
  1. Field intervention & follow-up
  • Once an alert is raised, dispatch field crews to perform surveys (acoustics, correlation, visual inspection).
  • Repairs are logged in the system, including volume saved, cost, and downtime.

AquaNRW supports task-assignment, status tracking and intervention logging.

  1. Performance measurement & continuous improvement
  • Monitor key performance indicators by zone: ILI, litres/connection/day, night-flow trend, leakage volume.
  • Compare pre- and post-intervention.
  • Update zone definitions if the network changes (new mains, changes in supply, customer growth).

AquaNRW’s dashboard offers visual trend analysis, KPI reporting and export functionality.

  1. Scale and refine
  • Expand vDMA coverage across the network, refine sensor deployment, and integrate with asset-renewal planning and pressure-management programmes.
  • Make the vDMA programme part of your broader NRW strategy (including apparent loss management, metering, and pressure reduction).

AquaNRW can scale to cover multiple zones and integrate with third-party systems (GIS, SCADA, asset management).

Australian context & key considerations

In Australia, many utilities and councils face large, dispersed networks, legacy infrastructure, constrained budgets and pressure from regulators or communities to reduce losses. Physical DMA segmentation can be expensive and disruptive. vDMA offers a practical alternative.

Some key considerations for Australian utilities:

  • Data quality matters: sensor accuracy, regular calibration, and communication reliability are foundational for analytics to work.
  • Hydraulic complexity: in meshed networks, defining “zones” can be non-trivial; virtual segmentation helps but still requires sound network understanding.
  • Field execution: analytics generate alerts, but they only deliver value when field crews respond and interventions are effective. Operational discipline is vital.
  • Linking to broader asset management: vDMA is one element — apparent losses, pressure management, main renewal and customer metering still matter.
  • Business case: demonstrating rapid ROI is crucial. The case study above shows how vDMA implementation can deliver measurable leakage reductions without wholesale network disruption.

Key metrics to track

To measure success, these metrics should be included in your monitoring regime:

  • Minimum Night Flow (MNF) per zone – baseline and trend.
  • Zone inflow minus authorised consumption = estimated leakage volume.
  • Infrastructure Leakage Index (ILI) – ratio of actual losses (CARL) to unavoidable losses (UARL). 
  • Leakage volume in litres per connection per day or litres per kilometre of mains.
  • Pressure performance: number of pressure transients, exceedances of threshold, mean operating pressure.
  • Field intervention metrics: number of alerts, number of field investigations, volume of leak located, cost per megalitre saved.
  • ROI/Payback: cost of flow/pressure sensor deployment + analytics platform vs saved water volume/cost.

Risks, challenges & mitigation

While vDMAs are powerful, they are not without risks:

  • Data integrity risk: poor sensor performance, gaps in telemetry, or inaccurate calibration degrade analytics. Mitigation: ensure sensor selection, calibration and maintenance programme are robust.
  • Zone definition risk: if zones are too large, hydraulically complex or insufficiently instrumented, the vDMA will not deliver meaningful insight. Mitigation: use a phased approach, start small, and refine segmentation.
  • Operational risk: analytics may generate alerts that are not acted upon — leading to “alert fatigue”. Mitigation: link analytics to a reliable operational process with responsibilities, KPIs and accountability.
  • Cost/benefit risk: sensors, communications and analytics cost money — without quick wins, the business case may falter. Mitigation: target high-loss low-cost zones first, use case study results to build a business case.
  • Integration risk: the vDMA programme must align with asset renewal, pressure management and other network strategies. Mitigation: ensure cross-functional collaboration (operations, maintenance, asset management, commercial teams).

Summary of Virtual DMAs

Virtual DMAs represent the next evolution in water loss management. By combining segmentation, real-time monitoring and analytics, utilities can transition from reactive to proactive management of leaks and losses — and significantly improve their NRW profile.

At Aqua Analytics, we understand the demands of municipal water networks, especially in the Australian and New Zealand context. With our AquaNRW software, we enable utilities to define virtual zones, deploy the appropriate instrumentation, monitor KPIs, detect events, and deliver actionable field tasks — all at a cost-effective price.

If you’re a water utility or council considering how to reduce losses, improve network visibility and deliver better outcomes without massive network disruption, contact us for a demonstration of AquaNRW and explore how a vDMA strategy could work in your system.