Managing wastewater assumes great importance in addressing the growing demand for fresh water and other raw materials, says the 2017 UN World Water Development Report.
But currently only 8% of domestic and industrial water is treated in the low-income countries, compared to 70% in high income countries, says the report.
Untreated water creates public health and environmental issues as the water that reaches rivers, lakes and oceans is contaminated with bacteria, nitrates, phosphates and solvents, it says. Endangering lives of millions, Pathogens from human and animal excreta pollute almost one third of rivers in Latin America, Asia and Africa.
In 2012, 842,000 deaths in low- and middle-income countries were linked to contaminated water and inadequate sanitation services, the report says.
““Everyone can do their bit to achieve the Sustainable Development Goal target to halve the proportion of untreated wastewater and increase safe water reuse by 2030,” said Guy Ryder, Chair of UN-Water and Director-General of the International Labour Organization.
“It’s all about carefully managing and recycling the water that runs through our homes, factories, farms and cities,” he added.
Wastewater is often reused in agricultural irrigation, but only a few countries — such as Israel and Jordhan — treat the water, making it safe. In industry, the report estimates, the market for waste water treatment is to increase by 50%.
The report, “Wastewater: The Untapped Resource,” published by the UN World Water Assessment Programme of UNESCO, also highlights the potential of wastewater as a source of raw material.
For instance, estimated 22% of global demand for phosphorus, a finite and depleting mineral resource, could be met by treating human urine and excrement. Organic material in the wastewater can be used to generate biogas.