A new study uses advanced modelling methods shows how much urban wastewater is used to irrigate crops around the world.

The researchers also estimated ‘indirect reuse’, which occurs when wastewater gets diluted but still remains a dominant component of surface water flows. Such situations account for the majority of agricultural water reuse worldwide, but have been difficult to quantify on a global level due to different views of what constitutes diluted wastewater versus polluted water.

The study found that the use of untreated wastewater from cities to irrigate crops downstream is 50% more widespread than previously thought.

Access the report here.

Photo credit: Sustainable sanitation via Foter.com / CC BY