Water footprint

A water footprint accounts for the freshwater consumed and polluted directly by an organisation and indirectly through its value chain. It connects products and operations with the places where water is withdrawn, rainwater is used and water quality is affected.

When to use it

• Answer the performance question: “How well do we safeguard the environment in the execution of our business operations?”
• Monitor the corporate-social-responsibility perspective.
• Identify water dependencies and risks across sites, products and suppliers.
• Prioritise action using both water volume and local scarcity or ecological impact.

Origins

Geographer Tony Allan developed the idea of “virtual water” embodied in traded goods. Arjen Hoekstra later introduced the water-footprint concept and extended accounting across supply chains, distinguishing green, blue and grey components. The Water Footprint Network developed a detailed assessment method, while related international standards added impact-oriented approaches. These methods answer different questions, so a report should state whether it measures volume, scarcity-weighted use, pollution or broader environmental impact.

What it is

Perspective: Corporate social responsibility perspective.

Key performance question: How well do we safeguard the environment in the execution of our business operations?

Water depletion and pollution are local phenomena: the same volume can have very different consequences in a water-abundant basin and a stressed one. A footprint therefore links consumption to geography, season, source and water-quality context.

The three components are:

Green water footprint:

rainwater stored in soil and consumed by crops or vegetation.

Blue water footprint:

surface water or groundwater consumed and not returned to the same catchment at the same time and quality.

Grey water footprint:

a pollution indicator expressed as the freshwater volume required to assimilate a pollutant load while meeting a specified water-quality standard.

Businesses use the assessment to reduce impact, manage operational and supply-chain risk, anticipate regulation and respond credibly to customers and investors. Brand benefit may follow, but claims must reflect actual basin-level outcomes rather than gross volume alone.

How to use it

Measurement