How much wastewater in the world is reused
How much wastewater in the world is reused stays small, even where the technology to do it already exists. Reuse means treating wastewater and sending it back into use for cities, farms or industry, instead of releasing it once and never touching it again. The World Bank counts only 53 million cubic meters of municipal and industrial wastewater reused worldwide each day, just 3% of all the fresh water that cities and industries withdraw, according to the World Bank Group 2025 Scaling Water Reuse report. The bank states that reuse capacity for industrial and drinking water use could grow 14% a year, and that investment could reach up to 340 billion dollars over the next 15 years if governments put the right policy and financing in place.
Treating wastewater at all is a separate, earlier problem
Reusing wastewater is a harder, later step than simply treating it before it goes back into a river or the ocean, and that earlier step is also far from finished. Official monitoring by the World Health Organization and UN Habitat counted only 56% of the world household wastewater as safely treated in 2024. That share swings widely by region, from 87.22% across Europe and Northern America, to 65.28% in Eastern and South Eastern Asia, 64.47% in Northern Africa and Western Asia, 36.64% in Latin America and the Caribbean, and just 19.42% in Sub Saharan Africa. Treated and reused are 2 different measures, and a place can treat most of its wastewater while still reusing almost none of it.
This chart measures whether wastewater is treated at all before release, not whether it is reused. The 3% reuse figure elsewhere in this article measures a separate, narrower question.
Show the numbers
| Europe and Northern America | 87.22 |
| Eastern and South Eastern Asia | 65.28 |
| Northern Africa and Western Asia | 64.47 |
| Latin America and the Caribbean | 36.64 |
| Sub Saharan Africa | 19.42 |
Turning wastewater back into drinking water is rarer still
Purifying wastewater all the way back to drinking quality, called potable reuse, happens at only 59 facilities worldwide, either already running or under construction, according to a December 2024 global count cited by University of Southern California Viterbi Magazine. 40 of the 59 are in the United States, and 16 of those 40 sit in Southern California alone. 10 are in Africa, 5 in Europe, 2 in Australia, and 2 in Asia, in Singapore and Manila.
These 5 regions add up to 59, the figure named in the dek and stat row. The count includes facilities still under construction, not only ones already running, and 16 of the 40 United States facilities are in Southern California alone.
Show the numbers
| United States | 40 |
| Africa | 10 |
| Europe | 5 |
| Australia | 2 |
| Asia | 2 |
Only 3 of the 59 skip sending the purified water through a river, lake or underground aquifer first, a method called direct potable reuse. The rest use indirect potable reuse, sending the water through that natural buffer before it reaches a tap. Adam Smith, who directs the Environmental Engineering Program at the University of Southern California Viterbi School of Engineering, says pushing already highly treated water into a groundwater aquifer or a surface water reservoir still carries a risk of recontamination, a problem Orange County, California, already faces.
California now lets utilities skip that step entirely
California adopted a law, AB 574, letting a water utility purify wastewater and send it straight into a drinking water system with no river or aquifer in between. The State Water Resources Control Board adopted the direct potable reuse regulations on 19 December 2023, and they took effect on 1 October 2024, the first statewide rule of its kind in the United States. A utility that meets the rule can now build a plant that turns wastewater straight into tap water, cutting out the step that Smith says otherwise raises the recontamination risk.