Half of global wastewater treated, rates in developing countries still lagging

February 08, 2021

A new study by scientists at Utrecht University and the United Nations University concludes that about half of global wastewater is treated, rather than the previous estimate of 20%. Despite this promising finding, the authors warn that treatment rates in developing countries are still very low. The study and its dataset were published Open Access in the journal Earth System Science Data.

Humans and factories produce vast quantities of wastewater per day. If not properly collected and treated, wastewater may severely threaten human health and pollute the environment.

144 million swimming pools

The authors use national statistics to estimate volumes of wastewater production, collection, treatment and reuse. "Globally, about 359 billion cubic metres of wastewater is produced each year, equivalent to 144 million Olympic-sized swimming pools," says Edward Jones, PhD researcher at Utrecht University and lead author of the study. "About 48 percent of that water is currently released untreated. This is much lower than the frequently cited figure of 80 percent."

While the results show a more optimistic outlook compared to previous work, the authors stress that many challenges still exist. "We see that particularly in the developing world, where most of the future population growth will likely occur, treatment rates are lagging behind," Jones explains. "In these countries in particular, wastewater production is likely to rise at a faster pace than the current development of collection infrastructure and treatment facilities. This poses serious threats to both human health and the environment. There is still a long way to go!"

Creative reuse

The main problem, especially in the developing world, is the lack of financial resources to build infrastructure to collect and treat wastewater. This is particularly the case for advanced treatment technologies, which can be prohibitively expensive. However, the authors highlight potential opportunities for creative reuse of wastewater streams that could help to finance improved wastewater treatment practices.

"The most obvious reuse of treated wastewater is to augment freshwater water supplies," Jones states. Treated wastewater reuse is already an important source of irrigation water in many dry countries, particularly in the Middle East and North Africa. However, only 11% of the wastewater produced globally is currently being reused, which shows large opportunities for expansion.

From 'waste' to resource

"But freshwater augmentation is not the only opportunity," says Jones. "Wastewater also has large potential as a source of nutrients and energy. Recognition of wastewater as a resource, opposed to as 'waste', will be key to driving improved treatment going forward."

However, the authors stress the importance of proper monitoring of wastewater treatment plants, accompanied by strong legislation and regulations, to ensure that the reuse of wastewater is safe. The authors also acknowledge public acceptance as another key barrier towards increasing wastewater reuse.
-end-
The data and associated journal article are freely available through PANGAEA and Earth System Science Data), respectively.

Utrecht University

Related Wastewater Articles from Brightsurf:

New material 'mines' copper from toxic wastewater
A team of scientists led by Berkeley Lab has designed a new material -- called ZIOS (zinc imidazole salicylaldoxime) -- that targets and traps copper ions from wastewater with unprecedented precision and speed.

SARS-CoV-2 RNA detected in untreated wastewater from Louisiana
A group of scientists have detected genetic material from SARS-CoV-2 in untreated wastewater samples collected in April 2020 from two wastewater treatment plants in Louisiana, USA.

Could COVID-19 in wastewater be infectious?
Bar-Zeev, and his postdoc student, Anne Bogler, together with other renowned researchers, indicate that sewage leaking into natural watercourses might lead to infection via airborne spray.

Researchers: What's in oilfield wastewater matters for injection-induced earthquakes
Specifically, he pointed out that oilfield brine has much different properties, like density and viscosity, than pure water, and these differences affect the processes that cause fluid pressure to trigger earthquakes.

Better wastewater treatment? It's a wrap
A shield of graphene helps particles destroy antibiotic-resistant bacteria and the free-floating genes in wastewater treatment plants.

Using electricity to break down pollutants left over after wastewater treatment
Pesticides, pharmaceutical products, and endocrine disruptors are some of the emerging contaminants often found in treated domestic wastewater, even after secondary treatment.

Anammox bacteria generate energy from wastewater while taking a breath
More energy-efficient wastewater treatment may be possible by harnessing anammox bacteria's surprising ability to 'breathe' solid-state matter.

IO hybrid adsorbent to remove hazardous Cadmium(II) from wastewater
In a paper published in NANO, a group of researchers from Hebei University of Technology, Tianjin, China have discovered an effective way to remove heavy metal Cadmium(II) from wastewater.

Using wastewater to monitor COVID-19
A recent review paper from an international research group shows how wastewater could provide a useful tool for monitoring COVID-19 and highlights the further research needed to develop this as a viable method for tracking virus outbreaks.

Rice engineers: Make wastewater drinkable again
Delivering water to city dwellers can become far more efficient, according to Rice University researchers who say it should involve a healthy level of recycled wastewater.

Read More: Wastewater News and Wastewater Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.