Monitoring SDG6 on water and sanitation

Indicator 6.3.1 – Wastewater treatment

6.3.1 Proportion of wastewater safely treated

Target 6.3 seeks to halve the proportion of untreated wastewater discharged into our water bodies – this page explains why and how to monitor progress towards the target, and what resources that are available for countries to do so.

The indicator tracks the percentage of wastewater generated by households and economic activities that is safely treated. The household component includes also on-site facilities, which is critical from a public health, environment and equity perspective because approximately two thirds of the world’s population use on-site facilities.

The level of treatment needed depends on the type of recipient; for on-site facilities in particular, this calls for consideration of the distance to groundwater bodies.

How to progressively Monitor?

Data on the household component of 6.3.1 will come from the monitoring of 6.2.1. For the economic activities component, an initial monitoring step would be to make estimations based on registers of economic activities, and to focus on hazardous industries.

As the monitoring develops, increasingly accurate data can be collected by institutions or utilities – for example, by using metres – who in turn may be able to provide information on treatment compliance.

Monitoring wastewater generated by different economic activities may prompt stricter enforcement of pollution laws and discharge permits. If a country lacks national targets for the safe treatment of wastewater, the monitoring of 6.3.1 is a good opportunity to develop these. Photo credit: ADB, Creative Commons Attribution.

On-site sanitation, such as latrines, is part of the wastewater challenge. Monitoring helps policy- and decision makers find out where to focus limited resources, for example, on improving on-site facilities or building treatment plants. Utilities often collect data on wastewater collection and treatment for management and regulatory purposes.

The World Health Organization (WHO) and the United Nations Human Settlements Programme (UN-Habitat) compile country data at the global level and supports countries in their monitoring efforts.