Water Offsetting

Water offsetting is a voluntary mechanism through which an organisation balances its residual water footprint by investing in projects that generate equivalent or greater benefits in terms of water availability, quality, and access in another location. Its objective is to achieve water neutrality or become “water positive”, analogous to carbon neutrality but focused on water.

Concept and evolution

Beyond internal reduction: after measuring and minimising their corporate water footprint, companies offset the remaining impact by funding external initiatives.‍

Water Stewardship: frameworks such as the AWS Standard integrate offsetting into broader basin-governance strategies.

Types of offsetting projects

• Efficiency and savings: replacing irrigation technologies with drip systems that free up volumes for the basin.
• Ecosystem restoration: reforestation of micro-basins, wetlands, and mangroves to improve infiltration and storage.
• Green infrastructure: managed aquifer recharge, weirs, and infiltration trenches.
• Access and sanitation: community drinking-water systems that reduce unaccounted-for water consumption.
• Water quality: treatment plants and constructed wetlands that reduce the grey water footprint.

Calculation of equivalences

Weighted offset volume = physical m³ × Scarcity factor × Quality factor

• Scarcity factor: AWARE or WSI values for the receiving basin.
• Quality factor: coefficient representing improvements in pollution (grey footprint).

Steps to implement an offsetting programme

1. Measure corporate water footprint (ISO 14046, WFN).
2. Apply the mitigation hierarchy: reduce and reuse internally before offsetting.
3. Select priority basins based on water stress and relevance to operations.
4. Identify projects with tangible, additional, and verifiable impact.
5. Conduct annual monitoring and third-party verification.
6. Communicate results transparently (GRI 303, CDP Water).

Benefits

• Operational resilience: replenishing water in strategic basins helps secure future supply.
• Social licence: strengthens relationships with communities and local authorities.
• ESG compliance: responds to investor expectations on natural-resource management.
• Co-benefits: biodiversity, carbon sequestration, and socio-economic development.

Challenges and criticisms

• Additionality and permanence: difficult to prove that benefits would not occur without the investment.
• Geographical equity: offsetting in distant basins may overlook local impacts.
• Heterogeneous metrics: lack of global standardisation for comparing water credits.

Case studies

• Beverage-sector replenish programmes: commitments to replenish 100% of the water contained in products through certified projects.
• Technology sector: “water positive” data centres financing wetland restoration in basins where they consume water for cooling.

Connection to other concepts

• Corporate water footprint: basis for determining the volume to offset.
• Water scarcity assessment: prioritises locations under high stress.
• Water offsetting vs. carbon offsetting: both require internal reduction as a priority and high-integrity credits.

Well-designed and independently verified water offsetting can complement reduction and stewardship strategies, contributing to basin water security and the achievement of SDG 6 and SDG 15. However, it must apply strong criteria for additionality, transparency, and local relevance to avoid superficial solutions.