Back to all insights
Home  /  Blog  /  Water Audit
Water AuditJune 20259 min read

What a water audit actually measures — and why non-revenue water is the number lenders ask about first

Water audits are increasingly required alongside flood risk assessments in ESG-linked financing. We explain how a water balance audit is structured, what non-revenue water losses reveal, and how to benchmark consumption against sector standards.

HYD
HYDRisk Engineering Team
Water & Flood Risk Specialists
NRW
Non-revenue water — the headline metric
IWA
Standard water balance methodology
30%
Sites without a documented water audit

A water audit quantifies every cubic metre entering a facility's supply system and accounts for where it goes — metered consumption, authorised unmetered use, apparent losses (metering error, theft), and real losses (leakage). The International Water Association's standard water balance format is the reference methodology most lenders and ESG auditors now expect.

Most facility operators can tell you what they pay for water. Far fewer can tell you how much of that water is actually delivering value versus disappearing through an aging pipe network or an unmetered process line. That gap between the bill and the reality is exactly what a properly scoped audit is designed to close — and closing it is increasingly a precondition for the ESG-linked financing terms many operators are now seeking.

Key finding

Non-revenue water — the portion of supplied water that generates no return, through either physical loss or unbilled use — is the single figure ESG auditors and lenders ask about first, because it is the clearest indicator of operational water stewardship.

01
Building the water balance

The audit starts from system input volume — everything drawn from mains supply, groundwater abstraction, or on-site sources — and reconciles it against metered billed consumption, unbilled authorised use, and calculated losses. Sub-metering at process, cooling, and sanitary level lets the audit isolate exactly where losses occur rather than reporting a single site-wide figure.

The fix

Install or verify sub-metering before commissioning the audit — a facility with no internal metering can only produce a top-level estimate, not a diagnostic audit.

02
Benchmarking against sector standards

A raw water-use figure means little without a sector benchmark. Water intensity per unit of production, per employee, or per square metre varies enormously by industry — comparing a data centre against a food processing benchmark produces meaningless conclusions.

The fix

Benchmark against the correct sector- and region-specific intensity metric, and disclose the benchmark source alongside the result.

"You cannot manage what you have not measured — and most facilities have never measured where their water actually goes."
— HYDRisk Engineering Team

Need a water audit for ESG reporting?

We deliver IWA-standard water balance audits with sector benchmarking as standard.

Get a free scope →
Topics:Water AuditESGCompliance
HYD
HYDRisk Engineering Team
Water & Flood Risk Specialists

HYDRisk delivers water audits and flood risk assessments across the US, Europe, the Middle East and Asia.

Related articles
Water Neutrality
Water neutrality explained
Water Neutrality · 10 min
Water · Solar
Why solar developers commission water audits
Water · Solar · 8 min
Regulatory
IFC PS1 and PS4
Regulatory · 10 min
Put it into practice

Ready to measure where
your water actually goes?

Tell us your facility type and reporting requirement. We'll return a proposal within 24 hours.

Get a free water audit scope →← Back to blog