The Global Water Crisis: Addressing an Urgent Security - Unu-inweh ...

Introduction
The implications of water scarcity on development are clear. At a fundamental level, water scarcity affects our capacity
to grow food. Agriculture uses the largest share of the earth’s freshwater resources, and it is obviously needed to supply
food to all. But agriculture is also critical as a pathway out of poverty for rural producers and as a means to supply lowcost
food to the urban poor. As water scarcity starts to constrain agricultural output, not only will the total volume of
agricultural products required for food and to feed livestock be affected, but the communities that depend on farming
for livelihoods will also face hardship in securing a living. There have already been two global food crises in the past five
years (in 2007-2008 and again in 2011), with soaring prices that have impacted producers, consumers and cities, especially
the urban poor. The long-term impact of unsustainable water use, together with increasing water variability caused by
climate change and manifested as floods and droughts, means that humans’ capacity to continue using agricultural water
the way it has been used in the past simply will not sustain humanity in the future. There is little doubt that putting water
on the global agenda is critical not just in order to feed 9 billion people in 2050 with less agricultural water than what
is available today, but also to address the critical development challenge of doing this in a safe, sustainable way while
protecting the livelihoods of the vast number of rural poor (Brown, 2011). This paper outlines some of the trends that are
intensifying the competition for agricultural water and presents the challenges of balancing environmental concerns with
those of human well-being. Future investments in water need to consider a range of options from different perspectives
in order to achieve this balance.
1. Understanding Scarcity
A common knowledge of water scarcity usually entails an understanding of the physical lack of water. Waterscarce
regions are those areas of the world in which water basins no longer exist, and where rivers no longer
reach the ocean because they have dried out from over-exploitation of water resources. Water-scarce regions
typically encompass drier and more arid agro-ecological zones, where water may have always been scarce. It has
now been estimated that 1.2 billion people live in areas of physical water scarcity (as shown in Figure 1). But there
is also what has come to be called economic water scarcity. Economically water-scarce regions are those that
still have water resources, but where people cannot access them because of a lack of infrastructure (Figure 1).
map 2 Areas of physical and economical water scarcity
Little of no water scarcity
Physical water scarcity
Approaching physical water scarcity
Economic water scarcity
Not estimated
Definitions and indicators
• Little or no water scarcity. Abundant water resources relative to use, with less than 25% of water from rivers withdrawn for human purposes.
• Physical water scarcity (water resources development is approaching or has exceeded sustainable limits). More than 75% of river flows are withdrawn for agriculture, industry, and domestic
purposes (accounting for recycling of return flows). This definition - relating water availability to water demand - implies that dry areas are not necessarily water scarce.
• Approaching physical water scarcity. More than 60% of river flows are withdrawn. These basins will experience physical water scarcity in the near future.
• Economic water scarcity (human, institutional, and financial capital limit access to water even though water in nature is available locally to meet human demands). Water resources are abundant
relative to water use, with less than 25% of water from rivers withdrawn for human purposes, but malnutrition exists.
Source: International Water Management Institute analysis done for the Comprehensive Assessment of Water Management in Agriculture using the Watersim model; chapter 2.
Figure 1. Areas of physical and economic water scarcity (CA, 2007).
Water, Food and the Development Challenge
Part 2
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