What is Water Scarcity, is Africa Really Water Scarce?

UN DEVELOPMENT GOALS:

'[…to] substantially reduce the number of people suffering from water scarcity by 2030.'

WHAT IS WATER SCARCITY, IS AFRICA REALLY WATER SCARCE?

In this post I will discuss and define water scarcity, by comparing two commonly used measurements. I then observe recent rainfall patterns across Africa and attempt to identify gaps in relation to rainfall increase and water scarcity.

Water security is a topic that is prominent in global political conversation. It serves as a starting point for dialogue particularly from organisations such as UN-water, IMF and the World Bank.

The infographic below highlights the main elements of water security.

Much of the discussion around water security centres itself around Africa, with Sub-Saharan Africa having the largest number of 'water-stressed' countries of any region.

Water stress 'occurs when , 2012 the demand for water exceeds the available amount during a certain period or when poor quality restricts its use' (European Environment Agency, 2017).

Water scarcity is defined as a 'shortage of renewable freshwater water relative to demand' (Taylor, 2009). It is contested in its definition and measurements, thus leading to further confusion on who is actually in need of a water scarcity alleviation. 

 A standardised measure of water scarcity is needed for terms so often thrown about by the media and international organisations. The figure below demonstrates the issues with multiple measurement indexes for water scarcity, producing varying results of how severe the problem is (White, 2012).

FIGURE 1:

Results of different water indexes on the threat to human water security, focusing on Africa (Vorosmarty et al. 2010).

A comparison of two measurements:

1. Water Stress Index (WSI) - Fallenmark and Lindh (1974)

Fallenmark presents a fairly straightforward approach to defining water scarcity, explicitly linking food security to fresh water availability (Fallenmark, 1986, 1989). Water scarcity Index is measured in terms of the number of people sustained by a single flow unit of water.

Fallenmark provided a summary of thresholds within the WSI to help segregate regions in severity of water for each person. This stretched from:

No stress:  <600 people/ flow unit

Water scarcity: 600–1000 people/flow unit

Water stress: 1000–2000 people/flow unit

Absolute water stress: >2000 people/flow unit

(Flow unit of water - defined as 106 m3year−1.)

Limitations:

Only measured at country level, therefore does not recognise regional differences in water availability.

It includes water resources such as groundwater, that may be un-accessible.

2. Water poverty Index (WPI) -    Sullivan, 2003

         

This index differs in that it measures water stress at household and community levels (Sullivan et. Al, 2003). It aimed to specifically highlight the links between poverty reduction and water availability (Taylor et. Al, 2017). The WPI is a step in the right direction, seeking to empower poorer populations in assisting decision making that determines interventions in the water sector, which has the greatest effect on their provisions of water access.

It highlights that people can be 'water poor' if they are income poor', as they cannot afford to purchase the clean water that is available (Lawrence et. Al, 2002).

Within this index, the following components are:

Resources

Access

Capacity

Use

Environment

Recent Rainfall Patterns:

Changes in distribution of extreme precipitation patterns have been observed across many parts of Africa, most of which can be linked to climate change and variability. Arid and semi-arid regions pose a threat to desertification of many regions, this can have severe impacts on vegetation, a high cost for many African countries that rely on low-productive, rain-fed agriculture (Below et al, 2007).

Significant declines in internal rainfall trends in tropical regions such as, The Democratic Republic of Congo and Equatorial Guinea have been observed (Hoscillo et. Al, 2014).

Adversely, opposing common perceptions, a proportion of regions in Africa  are  actually getting wetter. Data produced by the Climate Prediction Centre and the National Oceanic and Atmospheric Administration (NOAA) reveals that over the last decade, a drastic increase in the amount of rainfall across Africa has been observed (Fitch, 2015). Central Sahel, Senegal, Western Guinea and Mauritania are significantly wetter than the previous decade.

FIGURE 2:

 'Trend in rainfall over ten years. Blue = Wetter conditions, red = drier conditions' (Hoscilo et Al, 2014).

Distribution of water

My immediate thought is, if parts of Africa are increasing in precipitation, why are many countries considered water scarce?

One of the main issues is uneven distribution of water. This can be effected by many things including:

Governance

Accessibility

Affordability

Bibliography

Below R, Grover‐Kopec E, Dilley M. 2007. Documenting drought‐related disasters. J. Environ. Dev.

European Environment Agency, 2017. 'Water Stress'.

Fallenmark, M. 1986. 'Fresh water-time for a modified approach.'

Fitch, C. 2015. 'New African Rainfall Patterns'.

Lawrence, P. Meigh, J. Sullivan, C. 2002. 'The Water Poverty Index: an international comparison.' Keele Economics Research Paper

Sullivan, C. Meigh, J R. Giacomello. 2003. 'The Water Poverty Index: Development and application at the community scale'.

Taylor, R. Damkjaer. S. 2017. 'The measurement of water scarcity: Defining a meaningful indicator.'

White, C.. 2012. 'Understanding water scarcity: Definitions and measurements.' Australian National University.

Figure 1: Vorosmarty, C.J., et al., 2010. ‘Global threats to human water security and river biodiversity’, Nature, 467:555–61.

Figure 2: Hoscilo, A. Balzter, H.  Bartholomé, E.  Boschetti, M.  Brivio, P.  Brink, A.  Clerici, M and Pekel,F