Water Scarcity in Africa
Water scarcity now ranks as the third most concerning global risk, according to the World Economic Forum; water crises are emerging at all levels across entire regions and countries in Africa, although the nature of potential water crises differs from one country to another as well as within individual countries. Water scarcity may shortly emerge as one of the most significant constraints on Africa’s human-development prospects as well as on industrial development.
Water scarcity is different than water shortage or water stress; it specifically refers to scarcity due to physical shortage, or scarcity in access due to the faults in institutional systems to ensure a regular supply, or due to a lack of adequate infrastructure. [1]
Water Demand and Supply in Africa
Low and unpredictable water supply, coupled with a high and growing demand and poor use of existing water resources, make Africa a water-constrained continent despite some African countries exhibiting high water availability.
"Definition of national water scarcity index
The food and agriculture organization of the United Nation provides a very simple indicator of water scarcity of a country which is the renewable freshwater resources per person. Water stress starts when the water available in a country drops below 1,700m3/year per person. When the 1,000m3/year per person threshold is crossed, water scarcity is experienced. Absolute water scarcity is considered for countries with less 500m3/year."
Source: FAO (2016)
In particular three North-African countries (i.e. Tunisia, Algeria and Libya) are considered as water-scarce with an average annual availability below 500 m3 of water per capita, putting them in the ranks of absolute water scarce countries. On the other hand, water availability in sub-Saharan countries exceed the FAO recommended threshold 1700 m3/capita/year (See figure 1).
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Figure 1: Distribution of average annual water availability in Africa
[Source: Jemmali (2018)][2]
Oddly enough, North Africa has more than 90% coverage (drinking water and sanitation), while Sub-Saharan Africa experiences a contrasting case with less than 40% of the total population without access to an improved source of drinking water and sanitation facilities, proving that water availability and water scarcity are two different (yet related) concepts (See figure 2)[3].
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Figure 2: Access to water index in African countries
[Source: Jemmali (2018)][2]
The FAO estimates that in Africa, overall water withdrawal is about 227 km3/year of which 220 km3 are from freshwater resources and the rest is from desalination. According to AQUASTAT (FAO, 2016), the share of water withdrawal by the agricultural sector in Africa is the largest at approximately 184 km3 (about 81% of total withdrawals), mirroring global statistics. The next largest user of water in Africa is the municipal sector, which used about 33 km3 (about 15% of total withdrawals). Finally, the industrial sector accounted for about 9 km3 (about 4% of total withdrawals) of consumption.[4]
Water Ressources
Across the continent, average rainfall is about 670 mm per year, which is comparable to some European and North American areas, but higher evaporation rates in Africa mean a substantially lower share of precipitation contribute to renewable water resources. Distribution of rainfall across the continent is also disproportional with some areas receiving rainfall up to 1,700 mm/year (Indian Ocean island countries), while other areas barely receive 100 mm/year (North African countries).
Africa has 17 rivers with catchment areas covering over 100 000 km2 and it has more than 160 lakes larger than 27 km2, most of which are in the equatorial region and the sub-humid East African Highlands within the Rift Valley. So it is no wonder that surface water is the primary water resource for African.
Groundwater is also an important resource in Africa, it offers another potential way of meeting some of the supply increases. It is estimated that over 40% of Africans use groundwater as their main source of drinking water, particularly in North and Southern African countries.[6]
Exploitable surface water yield can be increased through the treatment of municipal wastewater. The latter is a significant resource in some countries, especially in North African countries where water scarcity is reality that states face. Two-thirds of which is then directly reused and the remainder is available as exploitable surface water. According to the latest AQUASTAT data, Egypt lead the pack with a reported 1,200 MCM of treated sewage per year (in 2016), followed by Morocco with 70 MCM/year (in 2008), and then Algeria and Tunisia with 50 (in 2016) and 42 MCM/year (in 2017) respectively.
Desalination plants can be another source of supply, even though it is an energy-intensive, so the gains in water supply must be balanced with the associated energy costs, which also require large amounts of water. Desalination also has a brine-disposal implication, which is easier to manage at the coast. The desalination of used water and sea water is being implemented on a small scale in Africa, with several countries including this technology as a strategy to deal with the water shortages including Algeria, Tunisia, and Ghana generating 855 (in 2016), 55 (in 2017), and 16 (in 2016) million cubic meters respectively[7].
The Future of Water Supply
In Africa, all sources of water supplies are being used: surface water, groundwater, water reuse and desalination.
"Over the years, the yield of water resource is changing in most of the African regions. The yield from a water resource is the volume that can be extracted at a certain rate over a specified period of time, this parameter is used to characterize the capacity of a water resource to serve as a long-term water supply.[5] Because the level of water in a water system, i.e. the flow varies from year to year and from season to season, the yield also changes from year to year."
The demand-supply balance is not the only possible water management solution for Africa. There are many other facts that will affect both the supply and demand of water resources. Climate change, however, could have a negative impact on the availability of both surface and groundwater, and diminish reliable yield over time.
To increase water supply, the plan is to increase investment in surface water infrastructure, mainly from dams. The strategy plans to increase surface-water yield, increase groundwater, reuse of wastewater, and increase the use of desalinated water in several water-management areas. Another way to reduce water demand is to decrease the volume of water that is lost through physical leakage or commercial losses, referred to as non-revenue water.
Municipal wastewater utilization is another opportunity to increase water supply. In addition, reducing non-revenue water represents an opportunity to decrease municipal water demand.
Water as a Constraint on Growth of Industrial Sectors
Over exploitation of water has its own set of acute environmental consequences on the environmental resilience of aquatic ecosystems. In terms of economic impacts, and the reliability of water supply for human consumption will also constrains growth, employment, as well as general human development.
At the same time, the economic and industrial development increasingly drives water demand, which trickles down to from water demand in the industrial process to increased pressure on the wastewater treatment. Most of this increased demand comes from the industrial sector even with the wastewater treatment facilities, which results in increasing overall water supply infrastructure resulting as in the increased release of more untreated wastewater is also produced, and possibly resulting in more contamination of water catchments areas.
However, behavioral changes in municipal consumption to ‘reduce water demand in urban areas' is a strategy that is proposing water-conservation and water-demand-management programs in many African countries. Reducing the volume of non-revenue water; i.e. water lost through leakage in the system; will also greatly curtail the rise in municipal water demand.
Thermoelectric power generation to drive the manufacturing and mining sectors is increasing the industrial water demand. The water needs in such industries is being balanced with the needs of other sectors like in paper industry as well as food industry.
In this respect, the paper industry is regarded as an extremely highly demanding water consuming industry. This could have been one of the reasons of the slow development of the paper manufacturing in some African countries. As shown in the following graph; “Water Scarcity in Africa by Countries with Operating Paper Mills”; the high water availability risk in countries like Algeria and Morocco, will be a major constraint in any further paper industrial development.
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Figure 3 - Water scarcity in Africa by countries with operating paper mills
In the next article, entitled “Water Usage in Paper Mills”, we will explore an explicit data to reflect the current water demand by paper industry all over the world.
[1]UNWATER (2018) Factsheet on water scarcity. Available at www.unwater.org
[2]Jemmali, H. (2018). Water poverty in Africa: A review and synthesis of issues, potentials, and policy implications. Social Indicators Research, 136(1), 335-358.
[3]United Nations (UN). (2012). The Millennium development goals report 2012, NY.
[4]FAO (2016). AQUASTAT database. Available at www.fao.org
[5]Leib, D. I., & Stiles, T. C. (1998). Yield Estimates for Surface-water Sources. BULLETIN-KANSAS GEOLOGICAL SURVEY, 159-170.
[6]African Studies Centre (2017) Water in Africa. Available on www.ascleiden.nl, Accessed on (2019/08/18)
[7]FAO AQUASTAT (2017) Desalinated water produced (10^6 m3/year) per country. Available on http://www.fao.org. Accessed on (2019/08/18)
