Confirm whether mandatory requirements apply
PUB states that large water users with net water consumption of at least 60,000 m³ in the preceding year must meet specified requirements. These include notifying PUB, installing private meters at key usage areas, appointing a Water Efficiency Manager and submitting annual Water Efficiency Management Plans for the required period.
From 2024, additional recycling requirements apply to certain new or expanded wafer-fabrication, electronics and biomedical or pharmaceutical projects meeting the stated water-use threshold. Confirm the detailed design and operating requirements at project inception.
Build a site-level water balance
- Map incoming potable water, NEWater, harvested water and other sources.
- Sub-meter processes, cooling, sanitation, kitchens, landscaping and tenant areas.
- Reconcile meter totals, bills, storage changes, discharge and estimated losses.
- Define business-activity indicators and intensity metrics that explain operational change.
- Retain meter, calibration, invoice and calculation evidence.
Prioritise efficiency and reuse
Start with leaks, operating discipline, cleaning practices, cooling systems and equipment settings. Then assess process optimisation, reuse, recycling and alternative water sources. Each initiative should state baseline, expected savings, capex, operating impacts, water-quality constraints, owner and verification method.
Connect water to physical climate resilience
Review site exposure to intense rainfall, flooding, coastal risk, heat, drought-related supply pressure and critical-utility interruption. Map dependencies on landlords, utilities, logistics and key suppliers. Integrate controls into business continuity, capital planning, insurance and climate scenario analysis.
Report decisions, not only consumption
Useful disclosure explains boundary, water sources, high-use sites, material dependencies, compliance status, targets, actions and performance. Avoid presenting a group-wide percentage reduction without explaining acquisitions, divestments, production changes or estimation methods.
Official sources used for this guide
Source position reviewed 2 August 2026. Confirm the latest requirements, guidance and eligibility criteria for your organisation.