Virtual water refers to the water used in food production and supply chains. Green water comes from rainfall while blue water is from surface and groundwater sources, which are being depleted faster than they can be replenished in many areas. Infrastructure development and poverty reduction are keys to ensuring access to sufficient and sustainable water supplies. Growing populations and economic development are exacerbating water scarcity issues, especially in arid and drought-prone regions.

1.  Virtual water : Also called
embedded water, is water
that has been used in the
production of food etc.
Includes resources also for
irrigation, processing and
packaging of produce.

2.  Green water: Water that comes
directly from rainfall or the soil.
Generally replenished, but climate
change will alter patterns of rainfall
and there could be a decline in many
parts of the world.
Blue water: Withdrawn from
ground-water or surface reserves. In
many areas blue water is being used
faster than nature replenishes it.

3. Infrastructure is the key to avoiding water
 scarcity. It needs to guarantee safe, fair and
regular access to water. Poverty is the
biggest barrier to water security.
Scarcity often has its roots in water
shortage, and it is in the arid and semiarid
regions affected by droughts and wide
climate variability, combined with
population growth and economic
development, that the problems of water
scarcity are most acute.

4. 

5. 
MDG 1: Access to water for domestic and productive uses (agriculture, industry, and other
economic activities) has a direct impact on poverty and food security.
MDG 2: Incidence of catastrophic but often recurrent events, such as droughts, interrupts
educational attainment.
MDG 3: Access to water, in particular in conditions of scarce resources, has important gender
related implications, which affects the social and economic capital of women in terms of
leadership, earnings and networking opportunities.
MDGs 4 and 5: Equitable, reliable water resources management programmes reduce poor
people's vulnerability to shocks, which in turn gives them more secure and fruitful livelihoods
to draw upon in caring for their children.
MDG 6: Access to water, and improved water and wastewater management in human
settlements, reduce transmission risks of mosquito-borne illnesses, such as malaria and
dengue fever.
MDG 7: Adequate treatment of wastewater contributes to less pressure on freshwater
resources, helping to protect human and environmental health.
MDG 8: Water scarcity increasingly calls for strengthened international cooperation in the
fields of technologies for enhanced water productivity, financing opportunities, and an
improved environment to share the benefits of scarce water management.

6. Millennium Development Goals
 (MDC)

7.  Around 700 million people in 43 countries suffer
today from water scarcity.
By 2025, 1.8 billion people will be living in countries
or regions with absolute water scarcity, and two-
thirds of the world's population could be living under
water stressed conditions.
With the existing climate change scenario, almost
half the world's population will be living in areas of
high water stress by 2030, including between 75
million and 250 million people in Africa. In addition,
water scarcity in some arid and semi-arid places will
displace between 24 million and 700 million people.
Sub-Saharan Africa has the largest number of water-
stressed countries of any region.

8. Water use has been growing far faster than the number of people.
During the 20th century the world population increased fourfold, but
the amount of freshwater that it used increased nine times over.

Already 2.8 billion people live in areas of high water stress, the
report calculates, and this will rise to 3.9 billion – more than half the
expected population of the world – by 2030. By that time, water
scarcity could cut world harvests by 30 per cent – equivalent to all
the grain grown in the US and India – even as human numbers and
appetites increase.
Some 60 per cent of China's 669 cities are already short of water.
The huge Yellow River is now left with only 10 per cent of its natural
flow, sometimes failing to reach the sea altogether. And the glaciers
of the Himalayas, which act as gigantic water banks supplying two
billion people in Asia, are melting ever faster as global warming
accelerates. Meanwhile devastating droughts are crippling Australia
and Texas.
‘The Independent’ Newspaper

9. 

10. Developing countries should invest in
 water management strategies that
combine infrastructure with "natural"
options such as safeguarding
watersheds, wetlands and floodplains.
Japan and Cambodia experience about
the same average rainfall - about 160cm
per year. While the average Japanese
person can use nearly 400 litres per day,
the average Cambodian must make do
with about one-tenth of that.

11. 
The principal cause of increasing water
stress is growing water withdrawals, and the
most important factor for this increase is the
growth of domestic water use stimulated by
income growth. Streams that are important
for small communities in Tanzania may go
dry for half the year, largely because people
are taking more and more water for
irrigating crops.

12.  Singapore's NEWater is produce from waste water supplies.
NEWater is supplied to industries for process use as well as
commercial and institutional complexes for air-con cooling
purposes. This frees up potable water for domestic use. Because
the area lacks enough watersheds and rivers to draw water for
domestic use, it imports water (as much as 40% of its supplies)
and has invested significant amounts of land to create water
catchments. NEWater contributes to the domestic potable water
supply.
To make potable water out of what goes down the drain and
toilet, Singapore's recycling plants use a three-step purification
process: micro-filtration, reverse osmosis, and ultraviolet
treatment. The end product meets drinking water standards set
by the World Health Organisation

13. 

14. Economic water scarcity occurs when water is available
but inaccessible because of a lack of investment in water
provision or poor management and regulation of water
resources. Much of the water scarcity of sub-Saharan
Africa falls into this category.
Signs of scarcity are plentiful. Several major rivers,
including the Indus, Rio Grande, Colorado, Murray-Darling,
and Yellow, no longer reach the sea year-round as a
growing share of their waters are claimed for various uses.
Worldwatch Institute

15. 

16. Water tables are falling as groundwater is over-
pumped in South Asia, northern China, the Middle
East, North Africa, and the southwestern United
States, often propping up food production
unsustainably. The World Bank estimates that
some 15% of India’s food, for example, is produced
using water from nonrenewable aquifers. Another
sign of scarcity is that desalination, a limited and
expensive water supply solution, is on the rise.
Worldwatch Institute

17. Worldwide dam construction has reduced from 1951-77
(360/year) to 1992 (170/year)
About 40% of worlds population live in river basins whose
watersheds are shared by more than two countries – power
of upstream nations
• Syria / Jordan / Israel have conflicts over the Jordan River
• Egypt / Sudan / Ethiopia have conflicts over the Nile River
• Iraq / Syria / Turkey have conflicts over the Tigris-Euphrates
Rivers
• Bangladesh / India have conflicts over the Ganges River

18. 
“Water is only a renewable resource if we
respect the ecological processes that
maintain and give stability to the water
cycle”
The right to use water comes with
responsibilities to preserve and protect
water must be considered to be more than
just a “resource” – it is the basis of life

19. 
The water required for a meat-eating diet is twice as
much needed for a 2,000-litre-a-day vegetarian diet.
When 50% of food is wasted after it leaves farmers'
fields, it leads to an equivalent water waste of 50%
because wasted food is also wasted water.
Each of us can make a difference if we first consider
the water implications of our lifestyles and the
"water footprint" we are leaving behind.

20.  Farmers are adopting more precise irrigation practices,
such as drip and sprinkle irrigation. For example, many
farmers in Nepal and India now regularly use low-cost drip
irrigation to grow vegetables. In sub-Saharan Africa, just a
little water - combined with improved crop varieties,
fertiliser and soil management - can go a long way. Farmers
can double the yield per hectare they currently harvest,
and double the amount of food produced per unit of water.
Over the last two decades in Asia, sales of pumps that allow
farmers to more reliably and precisely apply water to their
crops, have risen dramatically. Rice farmers are now also
saving water by a practice known as "wet and dry"
irrigation, rather than following the traditional practice of
keeping rice fields constantly flooded.