Progress on wastewater treatment – Global status and acceleration needs for SDG indicator 6.3.1

Abstract

Sustainable Development Goal (SDG) target 6.3 seeks to halve the proportion of untreated wastewater discharged into water bodies and includes two complementary indicators to monitor progress: the proportion of domestic and industrial wastewater flows safely treated (Indicator 6.3.1) and the proportion of bodies of water with good ambient water quality (Indicator 6.3.2). Indicator 6.3.1 aims to track the percentage of wastewater flows from different point sources (households, services, industries and agriculture) that are treated in compliance with national or local standards (UN-Water, 2017). The disaggregation and analysis of wastewater volumes and pollution loads by different sources can help identify heavy polluters, and consequently, apply the “polluter pays” principle to eliminate dumping, minimize the release of hazardous chemicals and improve treatment (UN-Water, 2018). This report presents a summary of available data on total wastewater flows generated and treated in 2015, as well as disaggregated analyses on flows from industrial sources in 2015 and households in 2020. The monitoring of the total and industrial components of indicator 6.3.1 relies on the aggregation of standardized national-level statistics previously validated by governments. The corresponding flows of wastewater generated and treated have been extracted from two existing harmonized international frameworks (the United Nations Statistics Division (UNSD)/United Nations Environment Programme (UNEP) Questionnaire on Environment Statistics and the Organisation for Economic Co-Operation and Development (OECD)/Eurostat Joint Questionnaire on Inland Waters) and by contacting additional national institutions and ministries or statistical offices. Data for the year 2015 have been selected based on data availability for analysis of the 2021 update of the total and industrial components of the indicator.