WIA-ENE-071 Phase 3 (Verification & Testing) does not ask whether a water system is described as efficient. It asks whether measured performance meets the targets set earlier. For conservation, that changes the question. Reducing consumption, trimming losses and reusing water are the means. The ends are a sustainable yield that meets projected demand, reliable service, affordable bills and a protected environment. Phase 3 checks that those ends are met, using data gathered over a defined monitoring period.
Three ideas from the specification run through this chapter:
Savings are measured against a baseline. Requirement R1.3 asks for current demand to be quantified by sector (domestic, agricultural, industrial and environmental). It also asks for future demand to be projected under population, economic and climate scenarios, and for opportunities for demand reduction and efficiency improvement to be identified. R1.3 further requires an assessment of vulnerability to water scarcity.
Without this baseline, a reported saving cannot be separated from a change in weather, population or economic activity. A year with unusually heavy rainfall lowers irrigation demand with no conservation effort at all. A shrinking industrial customer lowers bulk use in the same way. For this reason the specification pairs demand assessment with the hydrological work in R1.1. That work quantifies water availability under normal, drought and climate-change scenarios and builds water balance models at suitable spatial and temporal scales. A conservation programme is judged against the scenario it was designed for, not only against last year's meter readings.
The environmental sector is listed alongside the human ones. R1.1 asks for environmental flow requirements, recharge zones and critical habitats to be identified. Water "saved" by an upstream abstraction that dries a wetland is not a conservation gain under this standard.
For piped systems the central efficiency indicator is non-revenue water (NRW). The success criteria set the ceiling at below 20%. NRW is the difference between the water put into the network and the water that is billed. It is best understood through the water balance accepted across the utility industry, which divides system input into authorized and unauthorized parts. The worksheet below is an illustration of that standard practice. It is not a data format defined by WIA-ENE-071.
System input volume
= Billed authorized consumption (metered and unmetered, billed)
+ Unbilled authorized consumption (e.g. flushing, firefighting)
+ Apparent losses (meter under-registration, billing errors, theft)
+ Real losses (leakage on mains, service lines, tank overflows)
Non-revenue water
= System input volume - Billed authorized consumption
= Unbilled authorized + Apparent losses + Real losses
NRW (%) = Non-revenue water / System input volume x 100
target for Phase 3: < 20 %
The decomposition matters because the remedies differ. Real losses waste water physically. Apparent losses waste revenue and distort demand data, because consumption that is not metered correctly is not conserved, only hidden. A utility that reports one NRW percentage without the breakdown has not yet shown where its efficiency problem lies.
The standard asks that infrastructure meet international standards, that climate resilience be built in, and that provision be made for scalability (R3.2). It does not prescribe specific leak-control products. The following practices are widely established in the water industry and fit within those requirements.
Cutting NRW has diminishing returns. Beyond a point, the cost of finding the last leaks exceeds the value of the water recovered. The specification's requirement for cost-benefit analysis (R5.2) provides the framework for deciding where to stop. The 20% ceiling is the threshold to demonstrate in Phase 3. It does not oblige a utility to chase every last cubic metre regardless of cost.
Because R1.3 separates demand by sector, conservation measures are most credible when targeted at the sector that the baseline shows is largest or most wasteful.
| Sector (R1.3) | Typical efficiency levers | What verification looks for |
|---|---|---|
| Domestic | Fixture and appliance efficiency, leak repair on customer premises, metering and billing feedback, public education | Per-capita use that stays above basic-service access (> 20 L/person/day) while total demand falls |
| Agricultural | Scheduling irrigation to crop need, more efficient delivery methods, canal and conveyance maintenance, soil-moisture monitoring | Yield-supporting water supply with lower abstraction, using remote sensing and sensors where available (R6.1) |
| Industrial | Process water audits, recycling inside the plant, cooling-water management, substitution of reclaimed water | Documented reduction in freshwater intake per unit of output, backed by calibrated meters |
| Environmental | Protecting environmental flows, restoring recharge zones, nature-based solutions (R3.2) | Ecosystem health indicators that hold or improve |
Nature-based solutions appear in the standard beside conventional engineering. Protecting wetlands, restoring floodplains and managing catchments can store and recharge water in ways that complement pipes and tanks. They also reduce the pressure on engineered supply, which is itself a form of efficiency.
R1.1 requires all water sources to be characterized, with surface water, groundwater and non-conventional sources named explicitly. Non-conventional sources are the main route by which conservation becomes substitution: reclaimed wastewater, harvested rainwater and similar supplies take the place of potable water for uses that do not need that quality. The long-term vision of the standard also mentions promoting efficient use and circular economy approaches.
Reuse is a water quality problem as much as a quantity one. The water quality assessment in R1.2 asks for baseline quality at all sources and distribution points, for identification of contamination pathways, and for compliance with applicable water quality standards. Reuse schemes must therefore be fit for purpose. Treated effluent for irrigation or cooling must not be routed where it could be mistaken for, or cross-connected with, drinking supply. The Phase 3 success criterion of more than 95% compliance with applicable water quality standards applies to a supply that includes these sources, so substituted water cannot lower the compliance figure.
Price is a conservation tool, but the standard constrains how it may be used. R5.2 asks for tariff structures that balance cost recovery with equity. The quantitative criteria set two limits that pull in opposite directions: water costs below 3% of household income for basic service, and full cost recovery for operations and maintenance with adequate reserves.
Tariff design has to satisfy both. A common approach is a tiered structure in which a basic volume is priced low and higher volumes cost more, so the price signal falls on discretionary use rather than essential use. Whatever form is chosen, Phase 3 verification should show three things:
Financial results feed back into physical ones. Reducing NRW raises billed volume without new supply, and that improves the financial position the standard asks utilities to demonstrate.
Conservation claims rest on measurement. Requirement R6.1 asks for indicators covering water quantity, quality, access and ecosystem health. It also asks for defined monitoring locations, frequencies and methods, and for a data management system that ensures quality, accessibility and security. The requirement explicitly encourages integrating traditional monitoring with modern technologies such as sensors and remote sensing.
R6.2 sets the discipline that makes the numbers trustworthy:
For efficiency work, calibration is the critical item. A bulk meter with a systematic bias in one direction makes NRW look better or worse than it is. A bias in the other direction can hide a real leakage problem behind an apparently healthy percentage. Reviewers should expect calibration records to be part of the evidence for any loss figure. The phase also expects data completeness, since gaps in the monitoring period weaken statistical analysis and trend identification.
The success criteria in the specification include eight quantitative metrics. Those most closely linked to conservation and efficiency are summarized below, together with how each is typically evidenced.
| Metric | Threshold | Evidence pointed to by the standard |
|---|---|---|
| Water availability | Sustainable yield meeting projected demands | Water balance models and demand projections (R1.1, R1.3) |
| Water quality | > 95% compliance with applicable standards | Baseline and monitoring data (R1.2, R6) |
| System efficiency | < 20% non-revenue water (piped systems) | Water balance with calibrated metering |
| Access | > 20 liters/person/day, universal basic service | Access indicators and sector demand data |
| Affordability | Basic service < 3% of household income | Tariff analysis (R5.2) |
| Reliability | > 90% uptime/availability | Operational records |
| Financial sustainability | Full O&M cost recovery, adequate reserves | Financial management plan (R5.3) |
| Stakeholder satisfaction | > 80% approval in user surveys | Survey results and grievance records (R2.3) |
No single row stands on its own. A utility with 15% NRW but unreliable service, or with excellent reliability bought through unaffordable tariffs, has not met the intent. The qualitative indicators add equity and resilience. They ask for reduced disparities in access among socioeconomic groups and for demonstrated ability to manage variability and respond to disruptions.
Phase 3 typically runs six to twelve months. The milestones listed in the specification map naturally onto an efficiency programme:
| Milestone | Timeframe | Efficiency-related use |
|---|---|---|
| Performance Monitoring | Months 1-4 | Collect system input, billed consumption, pressure and flow data across all indicators |
| Data Analysis | Months 4-6 | Compute the water balance, identify trends and seasonal patterns |
| Impact Evaluation | Months 5-8 | Assess environmental and social outcomes of savings and tariff changes |
| Optimization | Months 7-10 | Act on findings, for example by targeting leakage zones or adjusting operations |
| Verification Audit | Months 10-12 | Independent third-party verification of results |
The critical-path items in the standard include an adequate monitoring period, data quality and completeness, availability of independent evaluators and timely corrective action. For efficiency work the monitoring period is especially important. Demand and leakage both vary through the year, so a short window can flatter or penalize a system depending on the season in which it falls.
Conservation programmes fail in recognizable ways, and several of the standard's requirements guard against them.
Deliverables help organize this evidence. The Regulatory Compliance Matrix, the Monitoring and Evaluation Plan and the Operations and Maintenance Manual together show how conservation measures are planned, run and checked. A Certification Readiness Assessment then identifies any gaps against the criteria before the independent verification audit.
Conservation and efficiency under WIA-ENE-071 come down to three linked tasks. The first is to establish an honest baseline of sector demand and available resource. The second is to find and reduce losses and wasteful use, starting from a water balance that separates real from apparent losses. The third is to prove the result with calibrated measurements, within the limits set by access, affordability, water quality and environmental protection. The numerical anchors are less than 20% non-revenue water, more than 20 liters per person per day, basic-service costs below 3% of household income and more than 95% quality compliance. They are meaningful only together and only when the monitoring behind them stands up to independent review.
Phase 3 verification ends with confirmed performance, optimized operations and a determination of readiness for certification. The next chapter follows the work from there. It covers the final review and sign-off of deliverables, the transfer of data, documents and tools to the Phase 4 team, and the planning and mobilization that carry the verified conservation results into the next stage of implementation.