"World Water Day 2017: Why Waste Water?"

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FACTSHEET
World Water Day 2017:
Why waste water?
INTRODUCTION
als, halving the proportion of untreated wastewater
and substantially increasing recycling and safe re-
World Water Day, on 22 March every year, is about
use globally.”
taking action on water issues. In 2017, the theme is
wastewater and the campaign, ‘Why waste water?’,
Progress towards target 6.3 will also help achieve
is about reducing and reusing wastewater.
the SDGs on health and well-being (SDG 3), safe
water and sanitation (SDG 6), affordable and clean
Sustainable Development Goal (SDG) target 6.3
energy (SDG 7), sustainable cities and communities
requires us by 2030 to “improve water quality by
(SDG 11), life below water (SDG 14), and life on land
reducing pollution, eliminating dumping and mini-
(SDG 15), among others.
mizing release of hazardous chemicals and materi-
1
FACTSHEET
World Water Day 2017:
Why waste water?
INTRODUCTION
als, halving the proportion of untreated wastewater
and substantially increasing recycling and safe re-
World Water Day, on 22 March every year, is about
use globally.”
taking action on water issues. In 2017, the theme is
wastewater and the campaign, ‘Why waste water?’,
Progress towards target 6.3 will also help achieve
is about reducing and reusing wastewater.
the SDGs on health and well-being (SDG 3), safe
water and sanitation (SDG 6), affordable and clean
Sustainable Development Goal (SDG) target 6.3
energy (SDG 7), sustainable cities and communities
requires us by 2030 to “improve water quality by
(SDG 11), life below water (SDG 14), and life on land
reducing pollution, eliminating dumping and mini-
(SDG 15), among others.
mizing release of hazardous chemicals and materi-
2
• 663 million people still lack improved drinking wa-
4
ter sources.
• By 2050, close to 70% of the world’s population
5
will live in cities, compared to 50% today
. Current-
ly, most cities in developing countries do not have
adequate infrastructure and resources to address
wastewater management in an efficient and sus-
tainable way.
• The opportunities from exploiting wastewater as a
resource are enormous. Safely managed wastewa-
ter is an affordable and sustainable source of water,
energy, nutrients and other recoverable materials.
• The costs of wastewater management are greatly out-
weighed by the benefits to human health, economic
development and environmental sustainability – pro-
viding new business opportunities and creating more
‘green’ jobs.
TOP LINE MESSAGES
WASTEWATER AND THE WATER CYCLE
• Globally, over 80% of the wastewater generated by
society flows back into the ecosystem without be-
Water has to be carefully managed during every
1
ing treated or reused.
part of the water cycle: from fresh water abstrac-
tion, pre-treatment, distribution, use, collection and
• 1.8 billion people use a source of drinking water
post-treatment, to the use of treated wastewater and
2
contaminated with faeces
, putting them at risk of
its ultimate return to the environment, ready to be ab-
contracting cholera, dysentery, typhoid and polio.
stracted to start the cycle again.
Unsafe water, poor sanitation and hygiene cause
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around 842,000 deaths each year.
1
On average, high-income countries treat about 70% of the wastewater they generate, while that ratio drops to 38% in upper-middle-income coun-
tries and to 28% in lower-middle-income countries. In low-income countries, only 8% of industrial and municipal wastewater undergoes treatment of
any kind (Sato et. al, 2013).
2
WHO/UNICEF (2014), Progress on drinking water and sanitation: 2014 update:
https://www.unicef.org/gambia/Progress_on_drinking_water_and_
sanitation_2014_update.pdf
3
WHO (2014), Preventing diarrhoea through better water, sanitation and hygiene: exposures and impacts in low- and middle-income countries:
http://
apps.who.int/iris/bitstream/10665/150112/1/9789241564823_eng.pdf
4
WHO/UNICEF (2015) Progress on sanitation and drinking water, 2015 Update and MDG Assessment
https://www.wssinfo.org/fileadmin/user_
upload/resources/JMP-Update-report-2015_English.pdf
5
UN Department of Economic and Social Affairs (2014), World Urbanization Prospects: 2014:
https://esa.un.org/unpd/wup/Publications/Files/
WUP2014-Highlights.pdf
3
Due to population growth, accelerated urbanisation
and economic development, the quantity of waste-
water generated and its overall pollution load are in-
creasing globally. However, wastewater management
is being seriously neglected, and wastewater is gross-
ly undervalued as a potentially affordable and sus-
tainable source of water, energy, nutrients and other
recoverable materials. It therefore needs to be seen
as a resource, rather than a burden to be disposed of.
There are many treatment processes and operational
systems that will allow us to use wastewater to meet
the growing water demand in growing cities, support
sustainable agriculture, and enhance energy produc-
tion and industrial development.
WASTEWATER AND CITIES
By 2030, global demand for water is expected to grow
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by 50%
. Most of this demand will be in cities and will
require new approaches to wastewater collection and
management. Indeed, reused wastewater may help
ment plants may not remove certain pollutants, such
address other challenges including food production
as endocrine disruptors, which can negatively affect
and industrial development.
people and the ecosystem.
Mainly in low-income areas of cities and towns with-
Examples:
in developing countries, a large proportion of waste-
Dual distribution systems delivering reclaimed
water is discharged directly into the closest surface
water.
Since 1977 in St Petersburg, Florida, USA,
water drain or informal drainage channel, sometime
a parallel network of pipes, separate from potable
without or with very little treatment. In addition to
water mains, has served a mix of residential proper-
household effluent and human waste, urban-based
ties, and commercial and industrial parks, enabling
hospitals and industries such as small-scale mining
them to use recycled water for irrigation, laundry,
and motor garages, often dump highly toxic chemi-
vehicle and building washing, and ornamental wa-
cals and medical waste into the wastewater system.
ter features.
Even in cities where wastewater is collected and
treated, the efficiency of treatment may vary accord-
Biologically purifying wastewater before discharg-
ing to the system used. Traditional wastewater treat-
ing.
The effluent volume from Schiphol Airport, Am-
6
UNHABITAT (2016), World Cities Report 2016: Urbanization and development:
http://wcr.unhabitat.org/wp-content/uploads/sites/16/2016/05/
WCR-%20Full-Report-2016.pdf
4
Wastewater is now seen as a potential resource and
its use, or recycling after suitable treatment, can pro-
vide economic and financial benefits.
Wastewater can be used within the business itself or
between several businesses through ‘industrial sym-
biosis’. Industrial water consumption is responsible
for 22% of global water use (UN-Water, 2012). In 2009
in Europe and North America, water consumption by
industries was 50% as compared to 4-12% in devel-
oping countries (WWAP, 2009). It is expected that in
rapidly industrialising countries, this proportion could
increase by a factor of five in the next 10-20 years.
Therefore, there is a strong incentive to use wastewa-
ter in-house and locally, based on cost savings alone.
Businesses can directly use some wastewater, pro-
viding it is fit for purpose. For instance, using process
water for cooling or heating, or rainwater from roof
collection or concrete aprons for toilet flushing, irriga-
tion or vehicle washing.
Examples:
sterdam, is comparable to that of a small city with
• An industrial ecosystem.
In Kalundborg, Denmark,
a population of 45,000. About half of the wastewa-
the by-products of one enterprise are used as a
ter originates from passengers and businesses at
resource by other enterprises, in a closed cycle.
the airport, 25% is discharged by aircraft and cater-
The Asnæs Power Station receives 700,000 m
3
of
ing, and the remaining volume is produced by other
cooling water from Statoil each year, which it treats
aviation-related businesses. The on-site wastewa-
and then uses as boiler feed water. It also uses
ter treatment plant biologically purifies water to a
about 200,000 m
3
of Statoil’s treated wastewater
quality fit for discharge into local waterways.
for cleaning each year. The savings to local water
resources are considerable: nearly 3,000,000 m
3
WASTEWATER AND INDUSTRY
of groundwater and 1,000,000 m
of surface water
3
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per year.
Societal and environmental pressures over recent
years have led to a growing movement for industry to
• Reclaiming water from mining.
The Witbank coal-
reduce its wastewater and to treat it before discharge.
fields are located around Emalahleni, a small city in
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Domenech and Davies (2011), “Structure and morphology of industrial symbiosis networks: The case of Kalundborg”, Procedia - Social and Beha-
vioral Sciences, vol 10, 2011, pages 79-89:
http://www.sciencedirect.com/science/article/pii/S1877042811000127
5
South Africa dealing with worsening water scarcity.
The Anglo American mining company built a water
treatment plant that uses desalination technology
to convert water from the mine into drinking water,
and treat industrial water so it can be safely released
into the environment. As an added benefit, in the
treatment process, gypsum is separated from the
water and used as a construction material. The plant
provides a safe and secure water source to the city,
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meeting 12% of Emalahleni’s daily water needs.
WASTEWATER IN AGRICULTURE
Partly to help maximise yields to meet demand, usage
of chemical fertilizers and pesticides has increased
in recent years, both in industrial and small farming,
making agriculture a potential source of environmen-
tal pollution.
Pollution of groundwater and surface water by agricul-
tural use of untreated or inadequately treated waste-
water is a major issue in many developing countries
Example:
where such irrigation is practised.
• Use of wastewater in farming.
It is estimated that
more than 40,000-60,000 km
of land is irrigated
2
Farmers are increasingly looking into non-convention-
with wastewater or polluted water (Jimenez and
al water resources, mainly wastewater, whether due to
Asano, 2008), posing health risks to farmers and
its high nutrient content or lack of conventional water
to eventual consumers of the agricultural products.
resources. If applied safely, wastewater is a valuable
Available technologies allow removal of almost all
source of both water and nutrients, contributing to wa-
contaminants from wastewater, making them suita-
ter and food security and livelihood improvements.
ble for every use. The WHO Guidelines on Safe Use
of Wastewater in Agriculture and Aquaculture and
Improved wastewater management can improve the
the Sanitation Safety Planning (SSP) approach pro-
health of workers, especially in agriculture, by reduc-
vides a comprehensive framework to ensure that
ing the risk of pathogen exposure. It can also create
health risks are managed to protect public health.
direct and indirect jobs in water-dependent sectors
Israel paves the way, where treated wastewater ac-
and beyond.
counts for 50% of irrigation water (OECD, 2011).
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For more information: “The eMalahleni Water Reclamation Plant in South Africa”:
http://www.iwa-network.org/filemanager-uploads/WQ_Compen-
dium/Cases/The%20eMalahleni%20Water.pdf
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