Water Treatment Level (OI9278)

This metric is intended to capture the level of water treatment enacted by the organization during the reporting period. Organizations may report the level of treatment for any water or effluents at the point of discharge, whether treated themselves onsite or sent to a third party for treatment. Both lagoon and mechanical treatment can be included, where appropriate.

This metric applies to all elements of water discharge, including used water, unused water, and effluents. Organizations may use this metric to disaggregate Water Discharged (OD0386) by volume of water treated. For sanitation-related investments, organizations should disaggregate and apply this calculation specifically to wastewater.

Treating water aims to improve water’s quality to make it more acceptable for an end-use, such as drinking, industry, or safe return to the environment, by removing or reducing existing water contaminants. Increasing population pressure is increasing the amount of wastewater. Untreated effluent is discharged to water bodies and terrestrial ecosystems, leading to nutrient surpluses (which can cause anoxic conditions and species loss) and the presence of toxic, often non-degradable compounds in ecosystems. Untreated wastewater contains pathogens that can contaminate drinking water. Treating and recycling polluted water can help tackle water shortages.

Minimum requirements for treatment might be specified by national, sub-national, or local legislation; in setting treatment levels, however, organizations should consider the impacts of their overall water discharge and the needs of other water users. For further guidance on treatment requirements, see SDG 6: Progress on Wastewater Treatment (https://apps.who.int/iris/bitstream/handle/10665/275967/9789241514897-eng.pdf?ua=1).