Activity data·Waste & water

How to measure emissions from Water

Water covers the supply and treatment of water used at sites your organisation owns or controls, including mains, borehole and wastewater sent for treatment afterwards. It's typically reported under Scope 3 Category 1 as a purchased good or service, distinct from energy or fuel use. Meter readings and utility invoices are the primary sources, since spend alone is a poor proxy for actual consumption.

Scope
Scope 3 Category 1
What activity data you need
m3, litre, $ Spend, £ Spend
Activity data
Waste & water
01

What counts as Water

Water activity data is the volume of water supplied to, and wastewater treated for, sites the organisation owns or controls. It includes mains water, borehole and other abstracted water, and the treatment or discharge of resulting wastewater and sewerage. It excludes water consumed by tenants in space leased out to others, following the same ownership and control boundary used elsewhere in your inventory.

Water sits in its own waste-water cluster rather than alongside energy and fuels, reflecting its different GHG Protocol treatment as a purchased good or service under Scope 3 Category 1 rather than direct combustion. A common double-counting risk arises at multi-tenant or serviced sites, where water charges may be bundled into a service charge — request a breakdown or use floor-area allocation rather than assuming water use is negligible. Water also covers both supply and treatment stages, which can be billed separately or together depending on your local utility structure, so check whether your invoice already includes wastewater treatment or whether it needs adding separately. As a reporting tip, water consumption is highly site-specific — a data centre and an office of the same size can have very different intensity — so avoid applying a single organisation-wide benchmark across dissimilar site types.

How to collect the data

Water meter readings, either from the utility's meter or a sub-meter, provide the most accurate m³ or litre figures and are usually available via supplier invoices. Where water is drawn from a borehole or private supply, on-site meters or abstraction licence records can substitute for a standard utility bill. £ or $ spend on water and sewerage charges can be used as a fallback where volumes aren't separately itemised, though this should be treated as a temporary measure.

02

What activity data you need

Collect the most specific physical unit available. Unit definitions are in Appendix I — Description of Units.

  • m3
  • litre
  • $ Spend
  • £ Spend
03

Which emission scope it falls under

Water activity data typically maps to Scope 3 Category 1 under the GHG Protocol. Confirm organisational boundary and ownership before reporting.

By emission scope

04

Sub-types available in the platform

All 8 sub-types available in the platform.

  • Borehole water: RO treated
  • Borehole water: Untreated
  • Grey Water
  • Water supply
  • Water supply and treatment: Average: UK
  • Water treatment
  • Water treatment: Sewerage: Average: UK
  • Water: Mains Average
05

Common questions

Does water used by tenants in space we lease out need to be reported?
No, only water consumed at sites you own or operationally control counts — water used by tenants in space leased out to others sits outside your reporting boundary.
How do I get water data at a site where charges are bundled into a service charge?
Ask the property manager or landlord for a breakdown of water and sewerage charges, or use a reasonable allocation basis such as floor area if a breakdown isn't available.
Do I need to report wastewater treatment separately from water supply?
Report both if your utility bills them separately; some invoices combine supply and treatment into a single water and sewerage charge, in which case a single combined figure is appropriate.
Is water from an on-site borehole reported the same way as mains water?
Yes, borehole and other abstracted water are reported under the same category, though selecting the correct subtype, such as borehole water treated or untreated, ensures the right factor is applied.
Can I use a per-employee water benchmark instead of metered data?
Metered or invoiced data should be used wherever available; a benchmark is only appropriate as a last resort for sites where no metering or billing data exists, and should be replaced with actual data as soon as possible.

By industry

Industries where this is material

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