Water and waste metrics

What water metrics are reported?

• Withdrawal: all water drawn into the company's boundary from surface water, groundwater, seawater, produced water or third parties such as municipal suppliers.
• Discharge: effluent and other water returned to surface water, groundwater, seawater or third parties.
• Consumption: water withdrawn and not returned, because it evaporated, was used in products or was otherwise lost; if it cannot be measured directly, it is withdrawal minus discharge, adjusted for any change in stored water.

GRI 303 uses megalitres and ESRS E3 cubic metres; one megalitre is 1,000 cubic metres. See ESRS E2 to E5.

How is water stress assessed?

Water stress compares the water withdrawn in a basin with the renewable supply available. GRI 303 points to the World Resources Institute's Aqueduct Water Risk Atlas and the WWF Water Risk Filter; under Aqueduct's baseline water stress indicator, a ratio of 40% to 80% is high and above 80% extremely high. Companies map each site by location, report withdrawal, discharge and consumption for sites in stressed areas separately, and update the mapping as the tools are revised. See nature and biodiversity.

What waste metrics are reported?

Total waste generated, in tonnes, split into waste diverted from disposal, by preparation for reuse, recycling and other recovery operations, and waste directed to disposal, by incineration with or without energy recovery, landfill and other disposal. Hazardous and non-hazardous waste are shown separately, and ESRS E5 also asks for radioactive waste where relevant and, in the revised standard, the share of waste whose final destination is unknown. GRI 306 adds whether treatment happened on site or off site. See ESRS E5.

Water and waste metrics in practice: a beverage company

A beverage company withdraws 600 megalitres from municipal supplies and 900 from groundwater, 1,500 in total, and discharges 900 megalitres of treated effluent. Two of its plants, which withdraw 700 megalitres, are in areas of high baseline water stress. It generates 12,000 tonnes of waste, of which 150 tonnes are hazardous.

Its water consumption is 1,500 minus 900, 600 megalitres, most of it water contained in its drinks; 47% of its withdrawal comes from stressed areas, which is where its water targets focus. Of its waste, 8,400 tonnes were recycled and 1,200 composted, so 9,600 tonnes, 80%, were diverted from disposal; 900 tonnes were incinerated with energy recovery and 1,500 landfilled. Had it counted the incineration as recovery, as some companies do, its diversion rate would have been 87.5%, which is why the basis must be stated. See ESG KPIs explained.

What are the common pitfalls?

• Counting rainwater harvested or water recycled on site as withdrawal, or counting recycled water twice.
• Reporting discharge without saying whether it was treated and to what standard.
• Using purchase invoices for waste without checking contractors' treatment records, so recycling rates are overstated.
• Calling waste-to-energy recycling, or not stating whether energy recovery counts as recovery.
• Leaving out construction, demolition or one-off waste that is part of the operations.

How should companies collect water and waste data?

Meter water at each intake and discharge point, keep utility bills and abstraction licences, and estimate unmetered sites with a stated method. For waste, require contractors to report tonnes by waste code and treatment route, reconcile them to invoices and transfer notes, and audit the main contractors. Collect both through the same calendar and controls as energy and emissions. See collecting ESG data across a group and internal controls over sustainability data.

This guide is general information. It is not tax or legal advice for your situation.