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12 5 July 2018 Global Freshwater Availability Trends Christopher Crellin Research Assistant Global Food and Water Crises Research Programme Summary Freshwater availability is vital for the survival of any country. A lack of freshwater can hinder agricultural productivity and industrial and economic development. Scarce amounts of surface water have led to the overuse of groundwater, further straining water supplies and adding to environmental degradation. A study, based on data collected from the GRACE satellites, tracked the global trends of freshwater availability between 2002 and 2016. An analysis of the satellite data identifies 19 hotspots that experienced dramatic water depletion over those 14 years. The analysis suggests that north-western China, northern and eastern India, North Africa and the northern Middle East are most likely to experience the greatest food and water threats by 2050. The study, however, also located regions where freshwater availability increased. To overcome food and water security threats there is a need to improve the level of management and governance, from the local to the international level. The development of multilateral, co-operative management arrangements, practices and initiatives for shared Key Points The NASA Gravity Recovery and Climate Experiment (GRACE) satellite mission tracked trends in global freshwater supplies from 2002 to 2016. An analysis of the satellite data identified 19 hotspots where there were dramatic increases in water stress. Some of that stress could be alleviated by the application of green solutions, such as wastewater recycling, to reduce the reliance on grey infrastructure, such as reservoirs. Countries need to develop multilateral, co-operative management practices and initiatives for shared water resources, including the fostering of transboundary water sharing agreements.

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Page 1: Global Freshwater Availability Trends · freshwater availability increased. To overcome food and water security threats there is a need to improve the level of management and governance,

12 5 July 2018

Global Freshwater Availability Trends Christopher Crellin Research Assistant Global Food and Water Crises Research Programme

Summary

Freshwater availability is vital for the survival of any country. A lack of freshwater can hinder

agricultural productivity and industrial and economic development. Scarce amounts of

surface water have led to the overuse of groundwater, further straining water supplies and

adding to environmental degradation. A study, based on data collected from the GRACE

satellites, tracked the global trends of freshwater availability between 2002 and 2016.

An analysis of the satellite data identifies 19 hotspots that experienced dramatic water

depletion over those 14 years. The analysis suggests that north-western China, northern and

eastern India, North Africa and the northern Middle East are most likely to experience the

greatest food and water threats by 2050. The study, however, also located regions where

freshwater availability increased.

To overcome food and water security threats there is a need to improve the level of

management and governance, from the local to the international level. The development of

multilateral, co-operative management arrangements, practices and initiatives for shared

Key Points

The NASA Gravity Recovery and Climate Experiment (GRACE) satellite mission

tracked trends in global freshwater supplies from 2002 to 2016.

An analysis of the satellite data identified 19 hotspots where there were

dramatic increases in water stress.

Some of that stress could be alleviated by the application of green solutions,

such as wastewater recycling, to reduce the reliance on grey infrastructure,

such as reservoirs.

Countries need to develop multilateral, co-operative management practices

and initiatives for shared water resources, including the fostering of

transboundary water sharing agreements.

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transboundary water resources and a shift to green solutions, will be crucial to the future of

water security within those regions.

Analysis

The global availability of freshwater is constantly fluctuating. The United Nations estimates

that by 2050, five billion people could suffer from water shortages. The global availability of

freshwater is affected by various stressors, including: climate change, population growth and

human-induced activities, such as deforestation and unsustainable agricultural practices.

The stressors have increased water demand and put pressure on freshwater sources,

including: rivers, lakes, aquifers, glaciers and reservoirs. The increased stress on freshwater

bodies requires adequate global, sustainable, management measures, which has been raised

as a key environmental challenge of the 21st century.

Groundwater is a vital source of water for agricultural, industrial and domestic activities. It

also helps to replenish streams, lakes, wetlands and other water-based ecosystems. A stable

source of freshwater is essential for the maintenance of regional food supplies, human and

ecosystem health, energy generation and the avoidance of social unrest.

A paper published in Nature analyses the results of a recent NASA global freshwater

availability study. The analysis accumulated data from NASA’s Gravity Recovery and Climate

Experiment (GRACE) satellite mission, which tracked trends in global freshwater supplies

from 2002 to 2016. The study categorises the drivers of changing freshwater availability into

natural variability from year to year, unsustainable groundwater consumption and climate

change. The analysis identifies 19 water depletion hotspots. Other areas show the

accumulation of freshwater due to hydrological changes. Simply put, those changes indicate

that wet land areas, including both the high latitudes and the tropics, are getting wetter and

dry land areas are getting dryer. If that trend continues, rainfall will become sparser in dry

regions, which, in turn, will increase their reliance on groundwater, further straining that

resource.

Agricultural irrigation is one of the most intensive uses of groundwater, especially in semi-

arid regions. The OECD states that groundwater is used for over 40 per cent of global

irrigation and is an indispensable input for food production. Amid climate change, where

drought is severe and continual development and population growth are leading to polluted

water bodies, groundwater is often a reliable alternative to surface water sources. In many

parts of the world, current irrigation practices are unsustainable and the continued

extraction of groundwater for such practices could lead to poorer overall security outcomes.

Industrial activities are also a cause for concern. Population growth and migration to cities

has led to an increasing rate of industrial development and increased levels of water

pollution. Globally, 80 per cent of municipal and industrial wastewater is discharged without

treatment. Untreated wastewater gets funnelled back into freshwater bodies, contaminating

the already limited supply. The decreasing availability of freshwater in many of the world’s

irrigated agricultural regions, as outlined in the study, needs further analysis to assess the

likely future security outcomes.

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Regions with Increased Freshwater

Increased freshwater availability is mostly due to anthropogenic influences and climate

change. Due to changes in the global hydrological cycle, freshwater is accumulating in far-

northern North America, Eurasia, India and in the wet tropics of Australia. Freshwater has

increased in those specific areas due to an increase in rainfall, a surge in dam construction

(which increases the water storage capacity of the region surrounding the dams) and an

increase in glacial melt flows.

The accumulation of water in the northern Great Plains of North America is the result of

above average precipitation for nine of the 14 years covered by the GRACE mission,

including flooding in 2010-11. Similarly, many of the lakes in the Tibetan Plateau also

accumulated water due to increased precipitation levels, as well as an increase in water flow

from glacial melt. The increase in east-central China, however, was caused by the surge in

dam construction that occurred throughout the region between 2002 and 2016.

The study states that in some regions the increase in freshwater availability was probably

caused by natural variation in rainfall. In central and southern India, for instance, the

increased availability of water was caused mainly by natural variation in the amount of

monsoonal rain. That observation was consistent throughout the course of the GRACE

mission, mainly in the mountainous and tropical regions of the world. In those regions,

periods of lower than average rainfall were followed by longer periods of greater than

Source: Nature

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average rainfall. Between 2001 and 2005, for example, the Amazon Tropics in Brazil received

less than average rainfall, followed by greater than average rainfall for six of the next ten

years, as the water cycle in the region intensified. The increase in glacial melt flows on the

Tibetan Plateau, which led to the filling and replenishing of nearby water bodies, further

increased freshwater availability in that part of the world.

Greater than average rainfall may, at first, seem like a positive development. As surface

water availability increases, due to more rainfall and increased storage in dams, agricultural,

industrial and domestic consumers reduce their reliance on groundwater. More intense

rainfall, increased glacial melt flows and dam construction can also have negative impacts,

however. Recent floods in East Africa have caused rivers and dams to overflow and damage

infrastructure; displacing thousands of people and sparking fear of water-borne disease

outbreaks.

Dams can also have negative environmental and agricultural impacts. During the

construction of dams, large areas of natural vegetation are cleared, the flows of rivers are

altered and the flow of nutrients downstream is reduced. Those changes can subsequently

lead to increased levels of soil salinity, reduced levels of water availability and the loss of

biodiversity, all of which can affect food security. The construction of 22 dams in Turkey over

the last 30 years, for instance, has decreased the flow rate of freshwater into Iraq and Syria.

Those two countries have been hit by severe drought and the decreased water flow in the

Tigris and Euphrates rivers has further magnified the issue of water availability, leading to an

increased reliance on groundwater for the irrigation of crops and domestic water needs.

These water security stressors are also linked to social unrest in the forms of protests and

political instability, particularly in Iran.

What could be done?

Regions that experienced an increase in freshwater availability during the course of the

GRACE mission and are forecast to experience a further increase in rainfall, must show

initiative in developing policies and projects to increase their resilience. They must focus on

water security, to ensure access to an adequate future water supply. There is a great

opportunity for such regions to capture and sustainably utilise their supply. On the other

hand, the opportunity could also be overlooked or squandered, causing detrimental

environmental, social and political turmoil.

Regions with Decreased Freshwater

By 2050, the regions that are most likely to be water stressed include parts of north-west

China, north and east India, and the northern parts of the Middle East and North Africa.

Those regions all have similar characteristics. They have: comparable climates, growing

populations, a high dependence on agriculture and are undergoing rapid economic

development. Some of them are also prone to political instability and regional conflict.

Xinjiang, a province in north-west China, and the greater Beijing region both experienced

intense depletion of freshwater during the GRACE study period. Rapid levels of development

and a heavy reliance on groundwater for agriculture mostly explain the huge groundwater

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losses. Xinjiang is one of the poorer provinces of China, with an estimated 1.6 million people

living below the poverty line in the southern part of the province alone. The lack of water

and outdated irrigation systems have weakened the agricultural development of the region,

causing it to miss out on the economic boom that much of China has experienced over the

past 30 years.

Agriculture is also an important economic sector in the greater Beijing region, which is

experiencing human-induced water depletion. The stressors of population growth and the

migration of people to Beijing have propelled urban development and increased the demand

for food. The increasing demand for food has led to the expansion of agricultural irrigation

within the greater Beijing region, putting further stress on water resources there.

Agricultural production in eastern China is hitting its limits. To gradually increase food

production, alleviate food supply restrictions and maintain food security, there is a greater

need to develop the western provinces of China. Consequently, the Chinese Government has

turned its focus to the development of the Xinjiang region. Those development efforts have

taken the form of agricultural development policies and the growth of its water-intensive

cotton industry. The Chinese Government recently announced that it will spend up to

US$300 million ($402 million) to improve outdated irrigation systems and promote water-

saving technology, to boost agricultural production. The irrigation systems will enhance the

development of the region and possibly reduce social and political tensions. As the

availability of water within the province declines, the policies and agricultural infrastructure

investments may be limited in their potential to overcome the current security issues, which

are driven by more than just water insecurity.

The Nature analysis also points out that freshwater availability in Bangladesh, Myanmar, and

northern and eastern India has declined. The loss of freshwater is attributable to a decrease

in monsoon season precipitation in the eastern region and intense levels of surface,

especially flood, irrigation for water intensive crops, such as rice and wheat. This region is

the third-most heavily irrigated area covered by the study. It is also home to the highest

density of rural poor in the world, who are highly dependent on agriculture for their food

and livelihood security. The region is also highly susceptible to climate change, which was

evident in the results of the GRACE mission, as the region experienced years of alternating

drought and floods between 2002 and 2016.

Agriculture is the backbone of the region. Crop yields and the water supply will be negatively

impacted as population growth and severe climatic pressures continue to increase. As this is

one of the most heavily irrigated regions in the world, freshwater availability will continue to

decline unless water conservation technologies are more widely adopted. The increasing

severity of weather events, driven by changes in the hydrological cycle, is a growing concern,

as Indian crop yields are highly variable from year to year. This affects food security to the

point where unexpectedly severe weather events, such as flash floods, could potentially

wipe out food supplies. Not only could it reduce the quantity of readily available food, but it

could also have an economic impact on the whole country. The reduction in crop supply

would see India increasingly rely on food imports, which could potentially lead to trade

imbalances. Similar conditions have occurred in Egypt.

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Of the four regions that are most likely to experience severe food and water threats by

2050, the Middle East, specifically the northern part of the region encompassing Turkey,

Syria, Iraq and Iran, will be most threatened. This is reiterated by the World Bank, which

states that the Middle East-North Africa region is a global hotspot for unsustainable water

use. This especially involves groundwater, where more than half of current water

withdrawals exceed natural rates of water recharge. It is also important to note that, by

2050, the region is expected to have the greatest economic loss from climate-related water

scarcity. This region is not as heavily irrigated as India or China, but there is a high degree of

competition for already scarce water resources.

The northern Middle East has a complicated water history compared to other regions. The

complication and competition arises in the form of dams, severe drought and regional

instability. The dams have altered river flow patterns restricting the flows of freshwater

between regions. Furthermore, drought has drastically increased the regional reliance on

groundwater, as water availability from other sources, like rivers, has diminished. Over the

past 30 years, Turkey has constructed 22 dams upstream on the Tigris and Euphrates Rivers.

This has decreased the flow rate by at least 40 per cent in Iraq and Syria. The reduced flow

rates in the rivers and the long-term drought have combined to increase the region’s

reliance on groundwater supplies for domestic and agricultural needs. In Iran, for example,

12 of the country’s 31 provinces could exhaust their aquifers within the next 50 years, with

surface water runoff expected to decline by 25 per cent by 2030. The Nature analysis,

however, has not accounted for the impact of regional instability and conflict on freshwater

supplies.

In the Middle East, water is often used as a tool or weapon to advance state agendas. In

Iraq, water has been used to secure political and military aims, further destabilising the

country. In one example, drawn from local accounts, the governor of Najaf diverted more

water than allocated to his own farmers to boost his popularity. A series of interviews,

conducted by National Geographic, also state that ISIS crafted a narrative that suggested

that the lack of rain in Iraq was not due to climate change but rather to a government plot to

drive out opposing ethnic groups. ISIS used this as a means of recruitment and to aggravate

tensions. Iran, the third-largest dam builder in the world, also uses water for political

motives. Rivers dammed across the country divert water to key areas, in efforts to gather

support from important parts of the country. The politicisation of water resources and

distribution could potentially result in severe conflict. Some tribes in southern Iraq, for

instance, have warned the Iraqi Government that a “war” could erupt in the absence of

suitable measures to resolve their water security concerns.

Some regions of Africa have also experienced freshwater loss, most notably across the arid

north of the continent in Algeria, Libya and Egypt. Although the negative trend was weak

compared to other regions of the world, it is important to note that precipitation levels were

seven per cent above regular levels between 2002 and 2016. From this it can be assumed

that the extraction of groundwater is the cause of the decline. Population growth and

migration to cities has fuelled economic development across the region and led to an

increase in the use of agricultural irrigation. Those practices have contributed to the over-

extraction of groundwater and the subsequent decline in freshwater availability.

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As the region develops and continues to industrialise, living standards will improve, which

will further increase demand for water, food and energy. Additionally, rising temperatures

produced by climate change will see evaporation rates increase and precipitation decrease.

This process will prolong droughts and increase the chance of flood events. The region has

also been scoured by internal conflict and political instability, leading to insufficient

governance of water resources. Libya and Algeria, in particular, have both experienced

greater levels of political instability and violence recently.

Implications

Evidently, there are specific implications associated with diminishing freshwater availability

in the regions discussed; however, there are several overarching stressors that are constant

throughout all regions. The biggest challenges include: high population growth rates;

unsustainable levels of groundwater extraction and management, mainly for agricultural

irrigation; and increasing levels of industrial development and regional instability. All the

regions discussed above are also situated in the semi-arid zones that are most likely to be

affected by climatic and hydrological changes, meaning that the global problem of declining

freshwater supply is going to get worse, especially in semi-arid climates.

These factors have reduced water security levels within the region, increasing demand and

the reliance on groundwater supplies to sustain current industrial, domestic and agricultural

activities. As population growth, industrial and economic development and consumption

patterns change, water is going to be constantly in demand. Consequently, without stable

sources of water countries will be affected economically, socially and environmentally. A

reduction in agricultural productivity, which is often associated with a reduction in water

availability, increases a country’s reliance on food imports. That reliance on imports, in turn,

increases the reliance on global commodity prices, which can potentially affect a country’s

terms of trade.

In some parts of the world, reliance on overseas food supplies has contributed to social

unrest and political turmoil – for example, the events that occurred in Egypt in 2010. Egypt

relies heavily on overseas supplies of wheat to meet domestic demand. When Russia banned

the export of wheat following a drought, that decision contributed to pressures that caused

increases in global prices. That spike in prices contributed directly to social unrest in Egypt,

which, in turn, drove the Arab Spring uprisings. In addition to the economic and social

disruptions, overuse of groundwater can also result in: the lowering of the water table;

increased costs as more energy is consumed; reduced supplies of surface water; and an

increase in the salt content in soils, reducing the arability of farmland.

Water security is a multidimensional problem. A recent report by US intelligence agencies,

concluded that ‘water problems – when combined with poverty, social tensions,

environmental degradation, ineffectual leadership and weak political institutions –

contribute to social disruptions that can result in state failure.’ Therefore, without the

correct implementation of policy, water management practices, technology and

infrastructure, countries with a growing reliance on groundwater could, by 2050, become

failed states, as freshwater availability is increasingly strained.

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Recommendations to Improve Water Supplies

Moving toward 2050, there will be many regions of the world facing severe water shortages,

as already experienced in parts of South Africa. To mitigate the stresses and stark

implications that come with the depletion of freshwater availability, a few key actions can be

taken. Those actions include: improved policies that encourage the adoption of water

efficient crops; sustainable agricultural infrastructure; the recycling of wastewater; and,

most importantly, a co-operative management of shared water resources, as well as the

fostering of transboundary water sharing agreements.

Agriculture is the biggest global water consumer and is a rising source of water pollution and

thus change in this industry will be the key to water conservation. The GRACE report calls for

the wider adoption of conservation agriculture. This would require: greater use of rainwater

and rainwater harvesting for irrigation, rather than drawing exclusively on natural water

bodies; crop rotation to maintain soil cover; increased crop diversification; and adopting

practices to reduce evaporation and run-off.

Governments are highly at risk of water shortages. In the most severe cases, water insecurity

often results in social unrest and political instability; therefore, governments need to take

the initiative and develop policies that incentivise the conservation of water. It will also be

governments that, as part of those policies, encourage the implementation of water saving

technologies and the improvement of irrigation and water management practices.

On a broader scale, according to the World Bank, countries need to begin to develop

multilateral co-operative management practices and initiatives for shared water resources.

Stakeholders at all levels of government and society should consider watershed

management practices that balance competing demands and defuse any potential conflict.

Those practices could include the development and implementation of transboundary

water-sharing agreements. For instance, the Indus Water Treaty between India and Pakistan

considers the Indus River as a shared water body. To comply with the treaty, both sides need

to negotiate any planned changes to the flow of the river and cannot act unilaterally.

Agreements like this are particularly necessary in regions such as the northern Middle East.

There is also a need to better utilise green infrastructure. Instead of replacing or building

more reservoirs to supply cities with water, a greater uptake of green solutions is needed.

These could be financed by green bonds and increased payments for ecosystem services,

such as forest or wetland conservation initiatives. There is also a huge opportunity to meet

water demand through the recycling of wastewater, as 82 per cent of the world’s

wastewater is not recycled. Private and public institutions could both begin to develop green

infrastructure and implement practices that take advantage of this opportunity.

Throughout history the world has continually faced the problem of ensuring water security.

There are several regions that by 2050 will be greatly threatened by increased water stress.

Therefore, to mitigate this threat an increased level of management, from a local to a global

level, is essential.

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*****

Any opinions or views expressed in this paper are those of the individual author, unless stated to be those of Future

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