LONDON, March 22 (Thomson Reuters Foundation) - Wastewater
from households, industries and agriculture should not be seen
as a problem but a valuable resource which could help meet the
demands for water, energy and nutrients from a growing global
population, a U.N. water expert said.
Globally, more than 80 percent of wastewater is released
into rivers and lakes without treatment with a negative impact
on health and the environment, according to the 2017 U.N. World
Water Development Report published on Wednesday.
Pollution from human and animal waste affects nearly one in
three rivers in Latin America, Asia and Africa, putting millions
of lives at risk, it said.
But wastewater contains nutrients such as phosphorus and
nitrates which can be turned into fertiliser, said Richard
Connor, editor-in-chief of the report.
Treated sludge can be turned into biogas that could power
wastewater treatment plants or be sold on the market, he added.
"Wastewater itself is a valuable resource, even the term
wastewater is an oxymoron," Connor told the Thomson Reuters
"We need to stop seeing it as a burden to be dealt with.
It's not a waste and should not be a waste, especially in this
world of water scarcity," he said by phone from Perugia.
THE "YUCK FACTOR"
With the world's population expected to grow by one third to
more than 9 billion by 2050, the world will need 55 percent more
water and 70 percent more energy, the United Nations says.
Population growth will also lead to a 70 percent increase in
demand for food, putting more pressure on water through farming,
which is already the biggest consumer of water.
More people also means more wastewater, including from
sanitation, which governments have pledged to improve as part of
development goals agreed by U.N. member states in 2015.
Increased wastewater is one of the biggest challenges
associated with the growth of informal settlements in rapidly
expanding cities in developing countries, the report said.
Connor said even though wastewater is a valuable resource,
what often stops governments from investing in treatment plants
is the cost while what puts people off using it is the "yuck
Yet the International Space Station has been using the same
water for 17 years, Connor noted.
"One morning it's tea, by the afternoon it's pee and then
the next morning somebody is shaving with it," he said.
A solution for governments is to invest in smaller,
decentralised treatment systems, which cost a fraction of
conventional plants and require less maintenance, Connor said.
He added that not all water needs to be treated to drinking
water quality but to a level where it is safe to use by
industries, municipalities, agriculture or for cooling in power
"You go for what's affordable and design the level of
treatment according to your needs," Connor said.
"The key word is 'fit for purpose treatment'."
(Reporting by Magdalena Mis @magdalenamis1; Editing by Katie
Nguyen. Please credit the Thomson Reuters Foundation, the
charitable arm of Thomson Reuters, that covers humanitarian
news, women's rights, trafficking, property rights, climate
change and resilience. Visit news.trust.org)