Wastewater - Turning Problem to Solution

Northern Ireland and France at 92 m 3 /year, 92 m 3 /year and 66 m 3 /year per capita, respectively. Conversely, most sub-Saharan African countries produce less than 10 m 3 /

and 11 per cent was intentionally reused (see figure 2.2). These statistics were produced based on reported and modelled data, and again, the authors have acknowledged uncertainty in the underlying data, as well as discrepancies in these numbers across geographic regions and by level of economic development. Different approaches to calculate outcomes produce different results, and the information provided for decision-making should be used recognizing these limitations. Improving the quantity and quality of data relating to wastewater and its recovery and reuse, including gender-disaggregated data, will be important for improving management. The issue of monitoring for wastewater management and reuse is picked up again later in this report as a persistent barrier. Are we on track to achieve SDG 6.3? There is still a need to drastically increase the expansion of wastewater collection and treatment capacity to meet SDG 6.3. Jones et al. (2022) estimated that China would need to increase treatment capacity by 40 billion m 3 /year by 2030; the United States by 15.9 billion m 3 /year, India by 14.9 billion m 3 /year and Indonesia by 11.6 billion m 3 /year. The question is what this increased treatment capacity will look like.

year per capita (Jones et al. 2021). How much is being treated?

There is an often quoted statistic that “over 80 per cent of wastewater is released to the environment without being treated or reused”. However, this figure has been difficult to substantiate. The SDG indicator 6.3.1 measures the proportion of domestic and industrial wastewater flows that are safely treated. However, the data reported in the 2021 progress report are predominantly for domestic urban wastewater flows, with industrial wastewater flows reported for only 14 countries. Where industrial wastewater has been reported, about one third undergoes treatment (UN-Habitat and WHO 2021). However, current reporting leaves important data gaps in understanding how much of the world’s industrial wastewater is treated. For domestic wastewater (considering rural and urban domestic wastewater) SDG indicator 6.3.1 data suggest that around half enters the environment without adequate treatment (UN-Habitat and WHO 2021). This is supported by an analysis by Jones et al. (2021), who calculated that for domestic and urban wastewater in 2015, globally, 63 per cent of wastewater was collected, 52 per cent was treated

Currently only 11 per cent of the estimated total volume of domestic and manufacturing wastewater being produced

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