Wastewater - Turning Problem to Solution

Country level estimates of wastewater production, collection, treatment and reuse

Production

Collection (%)

(cubic metre per year per capita)

No data 0 10 25 50100

No data 0 5 10 25 50

Treatment (%) No data 0 5 25 50 75

Reuse (%) No data 0 5 10 25 50

Source: Jones et al . 2021;

GRID-Arendal/Studio Atlantis, 2023.

Figure 2.2: Estimates of country level (a) domestic and manufacturing wastewater production (m 3 /year per capita), (b) collection (%), (c) treatment (%), and (d) reuse (%) at the country scale, based on 2015 data and reproduced from Jones et al. (2021).

is being intentionally reused (Jones et al. 2021). The planned reuse of treated municipal wastewater has been predicted to increase 271 per cent, from approximately 7 billion m 3 /year in 2011 to 26 billion m 3 /year in 2030 (Global Water Intelligence 2014). The untapped potential for wastewater reuse is around 320 billion m 3 /year, with the potential to supply more than 10 times the current global desalination capacity (Jones et al. 2021). This is likely to be a gross underestimate of the potential for wastewater reuse, due to data gaps. The best data available are for municipal wastewater, which comes from urban domestic and commercial sources, and any parts of industry or urban agriculture that are connected to the municipal sewer networks. Increasing the percentage of treated water being intentionally reused could help to relieve the increasing pressure on freshwater supplies.

Jones et al. (2021) found that reuse is highest in the Middle East and North Africa Region and in Western Europe, with high rates also in water scarce small island developing States. Approximately half (52 per cent) of intentional reuse of treated wastewater occurs in high-income countries. Reuse is lowest in areas where collection and treatment are also low (e.g. sub-Saharan Africa or South Asia), or in areas where there are abundant conventional water supplies (e.g. Scandinavia, where reuse is less than 5 per cent). Israel and Singapore have national reuse policies in place. In Israel, almost 25 per cent of the country’s water demand is met by reused water, and in Singapore, it can be 40 per cent (Kehrein et al. 2020). In 2015, China reclaimed 10–15 per cent of its wastewater in 2019, with ambitions to exceed and reach 15–30 per cent in 2020 (Xu et al. 2020).

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