A. W. Jayawardena
International Centre for Water Hazard and Risk
Management (ICHARM) under the auspices of
UNESCO,
Public Works Research Institute
1-6, Minamihara, Tsukuba, Ibaragi, 305-8516
Japan
Contents
 Introduction
 Current status
 Population growth
 Water availability
 Water stress and water scarcity
 Challenges for the future
 Drinking water security
 Food security
 Environmental security
 Disaster reduction
 Climate change
 Concluding remarks
Introduction
 One of the main water problems around the world today is
the lack of potable water. After oxygen, water is the most
vital ingredient for sustaining life. Food, which requires
water for growing comes next.
 Over one billion (1.1 billion) people in the world do not
have access to safe drinking water and about twice (2.4
billion) as many do not have access to proper sanitation.
 The consequences of not having access to safe potable
water are serious particularly in developing countries
which suffer from various types of water-borne diseases
some of which result in premature death.
 The main challenge for future is how to guarantee water
and food security to all inhabitants of the world.
Water withdrawals by sector (Source: IWMI, 2006)
Current status: Population growth
 Although the total water resources remain reasonably constant, the per
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capita share is continuing to go down as a result of increasing
population.
It is also predicted that the population will continue to increase until
about 2050. The positive trends can be attributed to a number of
factors such as improved medical facilities, low infant mortality rates,
increased life expectancy and increased food production.
The population which in 1750 was 791 million has exploded to 6.93
billion in July 2011 (en.wikipedia.org/wiki/World_population), with the
highest rate of growth of 2.2% per year recorded in 1963.
China and India alone have 1.339 (19.33%) and 1.21 billion
(17.46%)respectively.
Despite the past trends, it is also well known that continued increase is
not sustainable as the competition for resources will begin to dominate
the growth rate sooner or later.
An important resource that could dominate the growth rate is water.
World population
Population in 1000 millions
8,000,000
7,000,000
6,000,000
5,000,000
4,000,000
3,000,000
2,000,000
1,000,000
0
0
500
1000
1500
Year
2000
2500
Current status: Water availability
 Fresh water – only about 2.5%
 Includes the water content of ice caps and glaciers,
inland lakes, soil water, ground water, atmospheric
water and river and stream storage
 The extractable part is only of the order of about 0.5%.
 Sea water – remaining 97.5% (not suitable for human
use except by way of desalination)
 Although renewable and abundant in nature, fresh
water has spatial and temporal variability. It is this
temporal and spatial variability and the changing life
styles that lead to water stress and water scarcity.
Current status: Water availability……
 A country or region may be considered as “water-rich” or “water-poor”
by the per capita amount of water available.
 Water-rich countries include
 Greenland
 Iceland
 Gabon
 Papua New Guinea
 Canada
 New Zealand
 Water-poor countries include
 Botswana
 Chad
 Namibia
 United Arab Emirates
Ranking
Country
Renewable
freshwater
availability
(m3/capita/year)
1
Greenland
25
Bhutan
68
Nepal
70
Bangladesh
8,809
98
Japan
3,383
105
Pakistan
2,961
113
Sri Lanka
2,642
118
China
2,259
123
India
1,880
164
Maldives
World average
10,767,900
45,564
9,122
103
~ 14,000
Current status: Water stress and water
scarcity
 Water stress occurs when the available supply is unable to meet the
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demand during a certain period or in a certain area.
Water stress can occur as a result of the physical lack of water, poor
quality or being economically unaffordable.
Quantitatively, a region is considered as under water stress when the
annual per capita water availability is less than 1700 m3, and under water
scarcity when it is less than 1000 m3 (Falkenmark and Lindh, 1976).
Another indicator that has been used to quantify water stress is the
percentage of the land area under severe water stress. In terms of the
latter, Israel and Trinidad and Tobago each have 100% of the land under
water stress. (http://www.nationmaster.com/graph/env_wat_ser_strenvironment-water-severe-stress).
Water stress occurs in many countries, some to a lesser degree than
others. The sub-Saharan African region is perhaps the most vulnerable.
Water stress in some selected
countries
Ranking
Country
Percentage of land area
under water stress
1
Israel
100
4
Nepal
98.1
23
Pakistan
76.3
24
India
60.2
36
China
44.7
40
Sri Lanka
39.5
50
Bangladesh
22.1
62
Japan
9.5
93
Iceland
0
Current status: Water stress and
water scarcity….
 Water stress and water scarcity can lead to economic, social,
environmental and health problems. Lack of water in sufficient
quantities affects agricultural and industrial production, whereas lack
of water in acceptable quality affects the environment and health of the
community. Poor quality water is fertile ground for growth and
spreading of pathogenic organisms.
 Water stress can also be caused by political conflicts in landlocked
countries. When the upstream countries control the resources of
trans-boundary rivers inequitably, the downstream countries suffer.
Water has been the root cause of many international conflicts which in
some cases have led to wars.
 Although water is freely available in nature, it has an economic cost
when it is delivered to the consumer for domestic, agriculture or
industrial use. Therefore, water stress and even scarcity can occur in a
place with abundant natural water if the community is unable to afford
it. Such instances have led to many political and social issues when
attempts to privatize the water industry are made.
Challenges for the future: Drinking
water security
 The health of a nation depends upon the level of
cleanliness of the domestic water supply. It is a problem
that is often ignored or sidelined by developed countries as
it is only a problem of the poor and the developing
countries.
 Unlike a major flood, an earthquake or tsunami which
affect a small region with high population density, the
effect of the lack of drinking water is spread over vast areas
with relatively low population densities.
 From the media point of view, such widespread and
prolonged suffering receives much less attention compared
with that received for high impact type of disasters such as
earthquakes, tsunami and major floods.
Challenges for the future: Drinking
water security…..
 Arid and desert areas suffer from physical lack of water
and such areas also experience pollution problems.
 Traditional techniques such as rainwater harvesting,
and groundwater exploitation would be better
appropriate technologies than conventional water
supply technology.
 It is also important to introduce low cost water filters
which can be used in individual households. It is
estimated that $1 invested in improving access to safe
water can increase the GDP by $3-14.
Challenges for the future: Food
security
 The global average food intake has increased from 2250
kcal in 1961 to 2800 kcal in 2000, although, in South Asia
and sub-Saharan Africa, it still remains at 2450 kcal and
2230 kcal respectively (IWMI, 2006).
 This increase may be attributed to a number of factors.
Land and water productivity has increased with average
grain production from 1.4 Tons/ha to 2.7 Ton/ha during the
last 4 decades (IWMI, 2006).
 Global trade in food products also has increased thereby
increasing the flow of virtual water.
 On the negative side are the facts that the population is
still increasing, and that the increases are in areas where
productivity is low and with inadequate human and
economic capacities to upgrade their production.
Challenges for the future: Food
security…..
 It is a fact that grains have been the basic form of food for
all humans.
 With increasing affluence, meat, milk and fish
consumption have increased substantially thereby exerting
an additional water cost to food products.
 On a global scale, agriculture uses about 70% of the world’s
water resources, followed by industry which uses about
22%. (Domestic water accounts for about 8%)
 In recent years, many countries have embarked on the
production and use of biofuels in place of fossil fuels. This
practice also has added a further burden of our water
resources because of the additional quantities of water
needed for growing the bio species from which the biofuels
are extracted.
Challenges for the future: Food
security…..
 The challenge in this context is how to produce our food
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(and energy sources) at the least water cost.
Large scale crop production necessarily depends on
irrigation to ensure guaranteed successful harvest.
Rainfed cultivation on the other hand is weather and
climate dependent and therefore does not guarantee a
successful harvest every year.
The water efficiency in irrigated cultivation is always low.
Flooded irrigation results in evaporation from the free
water surface as well as from the bare soil.
In order to increase the water productivity, it is necessary to
reduce crop evapo-transpiration. Better and more efficient
techniques such as drip irrigation, low pressure sprinklers
are currently being used to increase the water productivity.
Challenges for the future: Food
security…..
 Food trade is another area that requires attention.
 It is not meaningful to attempt to grow food in water-poor
regions at high costs and consequent environmental
degradation.
 With global trade expanding, it is quite logical to grow more
food in water-rich regions and make them available as food
products to those in water-poor regions.
 However, in the present context, many countries aspire to be self
sufficient in food for strategic reasons. Such aspirations will not
be needed if fair and reasonable trade agreements and treaties to
share trans-boundary water resources are in place.
 Above all, concern for the well being of other human beings
should be the guiding principle for sharing the water resources
on earth.
Challenges for the future:
Environmental security
 Environmental pollution is a by-product of economic
development and goes unabated in many waterbodies as a
result of indiscriminate dumping of domestic, agricultural
and industrial wastes.
 When the release of wastes into such waterbodies exceed
their capacities to self purify, they will become ‘dead’ when
no living organism can survive.
 Slow accumulation of pollutants over the years in many
rivers (e.g. in China and India) has made them aesthetically
unpleasant and biologically and chemically toxic.
 Restoration of such rivers to environmentally acceptable
levels is costly and a fair and reasonable approach to
recover costs is to follow the polluter pay principle.
Challenges for the future:
Environmental security….
 Many countries have enacted legislation to address
this issue but the enforcement becomes difficult as
the costs are passed back to the consumers by the
polluters as increased costs of their commercial
products.
 How the benefits arising from development
activities should be balanced against
environmental costs is a major issue that needs to
be considered holistically in the context of the total
water environment rather than as isolated systems.
Challenges for the future:
Environmental security….
 Incidents of pollution caused by accidents such as the
one that occurred in Songhwa River in Northeast
China are also on the increase as more and more toxic
industrial ingredients are conveyed too frequently and
over long distances.
 Introduction of advanced methods of waste water
treatment such as membrane technology, recycling,
reclamation of waste water etc. help alleviate the
pollution problem to some extent.
 In the long term, an integrated approach of water
management in which all aspects of the water sector
are considered and optimized within the framework of
a single ecosystem appears to be the way forward.
Challenges for the future: Disaster
reduction
 Another challenge lies in the area of water-related disasters.
Water, despite being essential for all forms of life can also at
times be destructive.
 Floods, landslides, and debris flow are all triggered by excess
water. Many regions in the world are vulnerable to water related
disasters and the damage as well as the resulting casualties are on
the increase.
 According to a report by ICHARM (Adikari and Yoshitani, 2009)
based on data compiled by EMDAT, there have been 3050
incidents of flood disasters during the period 1900-2006 causing
economic damage to the extent of US$342 billion.
 It is also important to note that not only the numbers of disasters
are increasing but also the number of people affected too
because of migration of people into areas with better economic
prospects.
Trends in natural disasters
Challenges for the future: Disaster
reduction….
 A hazard becomes a disaster when the region and the
community are vulnerable and lack the coping capacity.
 Therefore any approach for mitigating the consequence of
a disaster needs to focus on reducing the vulnerability and
enhancing the coping capacity.
 Although there are many international and regional
initiatives aimed at disaster reduction, their
implementation is slow and lacks high priority due to
political, cultural and economic issues particularly in
developing countries.
 It should also be recognized that capital intensive
engineered approaches of disaster reduction practiced in
developed countries cannot be applied in developing
countries.
Challenges for the future: Disaster
reduction….
 It is only when the community attains a certain degree of
affluence that people will begin to think about disasters
and invest in disaster mitigation measures. For those living
at or below the poverty line, day to day survival by itself is a
disaster, and it is very difficult to get them involved
proactively on implementing mitigative measures.
 Although investment in disaster mitigation is considered as
a development issue in developed countries, there are other
areas of higher priorities where investments need to be
channeled in developing countries.
 More can be achieved by promoting non-engineered
approaches of coping with disasters as well as assisting in
upgrading the living standards of those in less developed
countries.
Challenges for the future:
Climate change
 Climate change is currently a hot topic. The
Intergovernmental Panel on Climate Change (IPCC)
has concluded that climate change is anthropogenic
and that greenhouse gases (CO2, CH4 and N2O) are the
cause of the current global warming.
 According to the IPCC report, the concentrations of
CO2, CH4 and N2O have increased from 280 to 379
ppm, 715 to 1774 ppb and 270 to 319 ppb respectively
between pre-circa 1750 and 2005.
 Global average temperature has increased by 0.74°C
during 1906-2005. Sea level has risen by 0.17 m in the
same period (57% due to thermal expansion; 28% due
to melting of glaciers/ice caps; 15% due to melting of
Greenland/Antarctica ice sheets).
Challenges for the future:
Climate change….
 Skeptics are of the view that the IPCC report is
politicized and accepted by Governments on a
consensus basis rather than on scientific logic, that a
Global Warming Petition refuting the conclusions of
the IPCC Report has been signed by 31,072 US
scientists including 9,021 Ph.D’s, that the IPCC Report
peer review process has not been independent and
thorough and that the increase in CO2 does not
necessarily increase the temperature at the same rate.
 There have been noticeable warming during 1909-1941
but the CO2 increase has not been significant.
Challenges for the future: Climate
change….(Lessons learned from COP 15)
 The first lesson is that climate change is not just a matter of
science but also a matter of geopolitics. Without improved
geopolitics, there can be no real fight against climate change.
The expectation at COP series that scientific-research results
would trump geopolitics was belied.
 The second lesson from the COP series is that to get an
international deal, there first must be a deal between the U.S.
and China. These two countries are very dissimilar, yet they have
a similar carbon profile: Each contributes between 22 to 24
percent of all human-induced greenhouse gases in the world.
 A third lesson from COP 15, being reinforced by the present
circumstances, is to have a more-realistic agenda. Too much
focus has been put on carbon cuts for nearly two decades, almost
to the exclusion of other elements. It is now time to disaggregate
the climate-change agenda into smaller, more manageable parts.
After all, a lot can be done without a binding agreement on
carbon cuts through national targets.
Climate change: Some facts
 Temperature which varies with position and time
(about -50 to +50°C) is used as an indicator of
warming. In this context, the definition of global
temperature is not quite clear. Also, the variation is
greater in the Polar Regions while it is reasonably
constant in the equatorial regions.
 Projections made into the future climate have many
uncertainties. These include model uncertainties,
data length and their representativeness, calibration
and validation issues, and the logic of projecting into
100 years or more into the future with a relatively short
window of observations.
Climate change: Some facts….
 Earth has gone through cycles of warming and cooling
in the past. Changes have persisted over decades and
sometimes over centuries.
 Although instrumental measurement of temperature
started in 1850, various proxy methods (such as tree
rings, ice cores, corals etc.) have been used to
understand Paleo-climatology.
 For example, the Holocene warm period (circa 18004000 BP), the Roman warm period (circa 200-500 AD,
the medieval warm period (circa 1000-1100 AD) and
the little ice age (circa 1200-1800 AD).
 It has been shown that there is a 1500-year cycle of
global warming.
As recorded in ice cores from Vostok, Antarctica, the temperature near the South Pole
has varied by more than 20 degrees Fahrenheit during the last 350,000 years. There
have been peaks of warmth approximately every 100,000 years. The temperature and
the carbon dioxide concentrations at the South Pole parallel each other. The rise and fall
of temperatures gives rise to the ice age/interglacial cycle.
Climate change: Some facts….
 Severe storms are another indicator of climate change.
They are caused by the temperature differential
between the polar and equatorial regions.
 During warm periods, the temperature of the Polar
Regions would be higher whereas in the equatorial
regions there would not be much change, leading to
fewer storms.
 It has been reported that there were less than half as
many major Caribbean hurricanes per decade during
1700-1850, than that have been recorded in the past 50
years
Climate change: Some facts….
 Such climate variabilities have taken place without human
intervention.
 The main factor that would have caused periodic warming
and cooling is the fluctuation of energy from the sun and
the oceans (El Nino and La Nina effects).
 Solar variability and orbital mechanics play a significant
role in controlling earth’s climate.
 Some cities have shown consistent temperature rises over
the past few decades (For example, Tokyo, Johannesburg,
Beijing etc). Some other cities have shown consistent
cooling over the past few years (For example, Jerusalem,
Quebec, Antananarivu etc.). Many cities in the world show
cyclic temporal patterns of temperature variation (New
Orleans. Cairo, Paris, New Delhi etc.). The winter in
2007/2008 in China has been the coldest in recorded
history.
Source: Goddard Institute for Space Studies
http://data.giss.nasa.gov/gistemp/
Climate change: Some facts….
 If CO2 is the main cause of global warming, the CO2
would first warm the upper atmosphere, and then the
earth’s surface. Measurements of atmospheric
temperatures by remote sensing show no sign of
warming of the upper atmosphere during the last
century.
Source: Kenneth Rundt (2008): Global
Warming – Man made or Natural?
Climate change: Some facts….
 Some scientists believe that the warming has peaked
and that the earth is more resilient than predicted.
 UN has warned that extreme winter has killed more
than 1 million livestock animals in Mongolia in
2009/10 winter, and is likely to harm its food supply
and worsen poverty. During zud (extreme winter), the
average temperature has reached -55°C when it should
have been about -35°C.
Climate change: Some facts….
 The IPCC has admitted some errors in their report (For example,
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the melting of the Himalayan glaciers by 2035). – Glacier-gate
Just before COP15 there was the "climate-gate," - the publication
of damaging e-mail and other documents from the Climate
Research Unit at University of East Anglia exposing highly
politicized scientific research in the form of manipulated or
suppressed data on human-driven climate change.
NASA satellites show that the Earth has become 6% greener as
the world has warmed over the past 20 years.
The temperature measurements made are normally in cities
where the ‘heat island’ effect can be significant. It is not clear
how this effect is taken into consideration in the IPCC
predictions.
Instrument calibration is another issue. Is it fair to compare
measurements made in the early days with the measurements
made today? There have been significant changes in the way
temperatures are measured and their levels of accuracies.
Climate change: Some facts….
 In a dynamic world, not only the climate, but many other things
are also changing. The most important change is the change in
population. The publicity given to population change is far less
than that given to climate change thereby distorting the real
issue.
 There are arguments and counter arguments which confuse the
public. What is really needed is factual information to enlighten
the public rather than opinions or conclusions based upon
uncertain information.
 Rather than addressing the issue on a global scale, more should
be done to clarify reality that exists locally. It is better to
measure any climate change locally and be convinced than being
told that there is climate change. The issue should not be like
the chicken little’s story - “sky is falling down”.
 Actions should be based on common sense regardless of whether
the earth warms or cools. Conservation should be encouraged
and practiced at all levels.
Climate change: Some facts….
 More people die from cold than from heat and no place on
earth is too hot for humans. Throughout human life, the
earth has been a better place to live under warm climate
than cold climate.
 Scientific information, data and the results of analysis as
well as the uncertainties of predictions should be made
public. Merely saying that the temperature in the year 2100
will be 2°C higher does not make scientific sense unless the
method, data used and the assumptions that have been
made to arrive at the result are also explained.
 Some scientists believe that the contribution by CO2 to
influence temperature is far less compared to water vapour,
solar variability (radiation and magnetic flux) and orbital
mechanics.
Climate change: Some facts….
 It is a fact that there is a pool of government sponsored
research money waiting to be grabbed for ‘climate related
research’. The findings of such research may be biased as
the researchers are motivated by their self interests to
secure continued funding rather than finding the truth.
The ‘inconvenient truth’ is that the issue is not universally
accepted.
 There is also the counter belief that the skeptics are on the
payroll of oil companies and others who have vested
interests.
 Is climate change the cause or the effect? Should we
address the cause or the effect? It is not necessary to use
climate change as a justification to reduce overconsumption and wastage. It should be natural.
 Should we follow a ‘global approach’ or a ‘local approach’?
Concluding remarks
 Responding to different challenges sometimes need addressing
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conflicting interests.
If any of the above challenges are taken in isolation, other challenges
may have to be overlooked or ignored.
In such situations, a holistic approach giving consideration to the long
term sustainability of the entire water sector would be the way forward.
An approach in which a balance is sought between development and
conservation, and where modern technology and traditional practices
go hand in hand would be ideal but the implementation of such an
approach requires the will and commitment of all stake holders to
share this precious resource of the planet earth in an equitable manner.
Failure to do so will result in a situation whereby the water-rich
countries can starve the water-poor countries when conflicts reach
critical stages.
In the not so distant future, water will take the place of oil as a political
and economic tool that can be used to manipulate communities and
governments.
Thank
you
for your
attention!