1. Water security and key megatrends in African cities

Throughout the world, an increasing number of countries are facing mounting challenges to address water risks and strengthen water security. These bring with them serious implications to meeting societal objectives, such as safe drinking water supply, wastewater management, food and energy security, improved health, sustainable ecosystems, poverty eradication and sustained economic growth. Water scarcity, water disasters and extreme weather events, such as floods and droughts, and failures of climate change mitigation and adaptation, rank as top global risks as assessed in the World Economic Forum’s Global Risks Report (2020[1]).

The OECD defines water security as the management of four water risks:

  • Risk of shortage and scarcity (including droughts): Lack of sufficient water to meet demand (in both the short and long run) for beneficial uses by all water users (households, businesses and the environment).

  • Risk of inadequate quality: Lack of water of suitable quality for a particular purpose or use.

  • Risk of excess (including floods): Overflow of the normal confines of a water system (natural or built) or the destructive accumulation of water over areas that are not normally submerged.

  • Risk of inadequate access to safe water supply and sanitation: Lack of access to safely managed water and sanitation services (Figure 1.1).

In many countries, water security is increasingly put in jeopardy by the effects of climate change, economic growth, urbanisation and demographic patterns, among others. Accessible and high-quality freshwater is a limited and highly variable resource in space and time, and future trends will affect water availability and quality. The OECD projects that by 2050, 40% of the world’s population will live in water-stressed river basins and water demand will rise by 55% (OECD, 2012[3]). Flood risks are anticipated to rise rapidly in both OECD countries and non-OECD economies with great potential for the loss of human life and property. Over-abstraction and contamination of aquifers worldwide are posing significant challenges to food security, the health of ecosystems and safe drinking water supply. In addition, by 2050 and despite global efforts, 240 million people are expected to remain without access to clean water and 1.4 billion without access to basic sanitation. Significant investment is required to renew and upgrade infrastructure, estimated at USD 6.7 trillion by 2050 for water supply and sanitation, and including a wider range of water-related infrastructure that could triple that cost by 2030 (OECD, 2015[4]).

The African continent is no exception to these observations as water security is already a major challenge for African countries and cities due to increased water demand tied to population growth, urbanisation and climate change impacts. Demographic trends are pushing water demand up with the African urban population projected to nearly double from more than 560 million in 2015 to 1.1 billion in 2050 (UN, 2015[5])). With 41% of the sub-Saharan African population currently living in cities, and a projected increase to 60% by 2050 (UN, 2015[5]), urbanisation will generate specific challenges related to access to quality drinking water and sanitation services. Climate change is also exacerbating the pressure on water resources with two-thirds of African cities estimated at “extreme risk” with regard to climate change impacts. The amount of gross domestic product (GDP) in African countries exposed to “extreme risk” will grow from USD 895 billion in 2018 to USD 1 397 billion in 2023 (Verisk, Maplecroft, 2018[6]), which represents 48% of the African continent GDP. For instance, in sub-Saharan Africa, the cumulative effect of the last decades indicates that floods and droughts alone are responsible for around 80% of disaster-related deaths and 70% of economic losses (Ndaruzaniye et al., 2010[7]). Damages to infrastructure, property and assets caused by tropical cyclones or flooding are among the more obvious impacts but droughts, crop failure and instability brought by climate change may also move millions of people towards cities through cross-border and rural migration (Verisk, Maplecroft, 2018[6]).

Furthermore, the latest monitoring results of United Nations Sustainable Development Goal (SDG) 6 “Clean water and sanitation” shows that significant or major challenges remain in all African countries, while half of them are showing a stagnating trend towards achieving the various targets associated with SDG 6 (Table 1.1).

African cities participating in the OECD Survey on Water Governance carried out over the period of May to September 2020 (Annex A and B) acknowledge their concomitant exposure to many of the above water risks and challenges. Floods and insufficient access to water and sanitation come first as the most prominent challenges to date, followed by other persistent challenges related to water pollution, water scarcity and droughts, ageing water infrastructure, waterborne diseases and, last but not least, water use competition (Table 1.2). The following sections put these water security challenges into perspective to provide a continental overview.

Worldwide, floods are affecting 2.5 billion people, representing more than 55% of all fatalities (EM-DAT, 2020[10]) and more than 30% of global economic losses from natural disasters (Hallegatte et al., 2013[11]). Floods are the most frequent and widespread water-related disaster in Africa, particularly in sub-Saharan Africa where 654 floods affected 38 million people in the last 33 years (Tiepolo, 2014[12]). In the past 15 years only, floods and landslides have affected 38 million people in Africa and caused damages estimated to more than USD 4 billion, with Eastern and Western Africa being the most affected regions (Table 1.3).

In Kampala, Uganda, annual flooding from extreme convective storm rainfalls with an average duration of two hours or more increased from five events in 1993 to ten in 2014 (Douglas, 2017[13]). In Nigeria only, the 2012 flood disasters affected 32 states (on a total of 36) and an estimated total of 7.7 million people (Nkwunonwo, Whitworth and Baily, 2016[14]). More recently, the 2020 East Africa floods affected at least 700 000 people in Burundi, the Democratic Republic of the Congo, Djibouti, Ethiopia, Kenya, Rwanda, Somalia, Tanzania and Uganda.

Flood risks (whether they are flash pluvial, costal or fluvial) in African cities are largely exacerbated by rapid urbanisation, uncontrolled urban growth and unregulated informal settlements in the low-lying floodplain areas. Flash floods result from high-intensity rainfall mostly occurring in steep slopes. Pluvial floods usually happen in urban areas in which drainage system capacity is overwhelmed by intense rainfall (Begum, Stive and Hall, 2007[15]; Houston et al., 2011[16]; Merz, Thieken and Gocht, 2007[17]) (Vojinović, 2015[18]). Fluvial floods are triggered by excessive rainfall over a few hours causing a river to overtop natural or artificial defences and flood urban areas (Vojinović, 2015[18]). Coastal floods usually affect cities that are close to the ocean or the coasts as a result of seasonal storm surges (Vojinović, 2015[18]). The Ogunpa flood disaster that occurred in Ibadan, Nigeria, which led to more than 200 deaths and destroyed assets worth millions of Nigerian Naira, was a combination of flash, fluvial and pluvial flooding (Etuonovbe, 2011[19]).

Urbanisation which amplifies soil sealing in the built environment prevent rainfall from infiltrating into the soil, increasing the rate and volume of runoff during rainfall events. In Kampala, Uganda, the construction of unregulated structures in informal settlements reduced rainfall infiltration significantly, increasing runoff to six times more than what would occur on natural terrain (ActionAid, 2006[20]). While some of the increase is likely due to climate change, it also largely results from land cover change. Thus, even moderate storms produce high flows, with more important and more frequent floods (ActionAid, 2006[20]) (Satterthwaite, 2008[21]).

The urban poor and those living in unplanned urban settlements are disproportionally affected by flooding (see Douglas et al. (2008[22]) for examples) as, for instance, these settlements are commonly built on marginal land including flood-prone areas, as illustrated in cities like Lusaka (Zambia) (Nchito, 2007[23]), Port Elizabeth (South Africa) and Johannesburg (South Africa) (Viljoen and Booysen, 2006[24]). In addition, the poor materials used for construction increase flood damages and fatality in informal settlements (Pharoah, 2014[25]). Frequent floods not only damage properties and result in direct loss of life but also disrupt traffic and expose people to health risks because of exposure to sewage, industrial waste and waterborne disease (Lall, Henderson and Venables, 2017[26]).

According to JMP reporting (WHO/UNICEF, 2019[27]), urban access to safely managed piped water ranges from 9% in Liberia to 99% in South Africa, with upward and downward evolution from 2000 to 2017. Downward evolutions underline the difficulties that cities are facing to expand water infrastructure in a context of urban population growth and unplanned urbanisation (Table 1.4). It is estimated that the total number of people living in urban areas with a perennial water shortage will increase from 24 million in 2000 to 162 million by 2050 (McDonald et al., 2011[28]).

Disparities related to urban water access across African countries are linked with the characteristics of urban habitat; but national averages also mask huge intra-country disparities, within and across cities, and between urban and rural areas, depending on where infrastructure and public services are concentrated. They tend to be mostly located in central and planned areas of African cities, while access to services declines when moving away from city centres. For instance, in Côte d’Ivoire, urban audits in 2013 showed that peri-urban and informal settlements are lacking adequate infrastructure and public services that are on the contrary present in the core of the cities. In Accra, Ghana, access to piped water, waste disposal and toilet facilities decreases as the distance to the city centre increases (Vinay, 2017[29]). The same situation is observed in Maputo, Mozambique.

Population growth and rapid outward urbanisation, among others, are already overwhelming existing urban infrastructure and challenge the capacity of institutions to respond to water demand. Economic growth and the emergence of a middle class with growing water needs will further add to that water demand. This is particularly alarming in a context of climate change and water scarcity. Some African cities are expected to be particularly affected by this evolution, like Bamako (Mali), Kampala (Uganda), Lagos (Nigeria), Niamey (Niger) and Ouagadougou (Burkina Faso) as they are in areas at high risk of water stress (Vörösmarty et al., 2010[30]).

Usually, poor people living in informal settlements have to rely on multiple water sources (e.g. boreholes, rain harvesting, etc.) with increasing health risks due to unsafe drinking water. Nevertheless, some African cities have managed to provide access to improved piped water to poor people.

  • For instance, Dakar, Senegal, managed to reach the poorest 40% of the urban population either by connecting individual properties on premises or through public stand posts in the proximity of dwellings (Figure 1.2).

  • The city of Cape Town provides free basic water and sanitation services to residents in informal settlements with 1 water tap per 25 families within a radius of 200 metres, and a minimum of 1 toilet per 5 families. As a whole, the city provides and maintains over 10 000 communal standpipes (taps) and over 50 000 toilets regularly cleaned (Box 1.1).

In a vast majority of African cities, in addition to formal utilities providing access to water, there are several informal water vendors.1 They tend to fill the gaps left by incomplete or inadequate piped water coverage (Box 1.2). Where there is incomplete coverage, informal markets fill residual needs and where the piped water reliability and quality is low, consumers turn to alternative supply sources. Thus, nearly half of the urban African population relies on small-scale providers for a share of their water supply (Kariuki, 2005[34]).

In Ouagadougou, Burkina Faso, the National Office of Water and Sanitation (ONEA) does not have a formal mandate to serve informal settlements as dwellers commonly lack legal titles to occupy the land. To overcome this issue, the utility provides water up to a metering point at the limit of the settlement and then has delegated the service provision within the settlement to small-scale providers. These operators either connect individual premises or set up standpipes. ONEA supplies connection materials and reimburses installation costs to informal operators to encourage the expansion of connections. Although informal operators are allowed to sell water at a higher tariff than ONEA, the price they charge is controlled by ONEA to reduce the risk of local monopoly power and excessive tariff level. The tariff policy with regard to standpipe, fountains, buckets or casks supply is published on the ONEA website. In 2015, 7 578 connections had been installed in 5 informal settlements of Ouagadougou (Figure 1.3).

In Maputo, 94% of households have access to piped water. The utility Águas da Região de Maputo reports a water coverage rate of 44% of the population, while about 500 small-scale providers manage over 800 piped systems and supply water to 50% of the population mostly through yard taps (Box 1.3).

In Accra, Ghana, about 80% of residents have access to drinking water, half through piped water into premises and half through private vendors. The latter share has more than tripled, rising from 13.8% in 2010 to 43.1% in 2014 (Guzmán and Stoler, 2018[41]), due to rapid urbanisation combined with underinvestment in infrastructure. The cost of water from informal vendors is generally five to seven times higher than piped water (Vinay, 2017[29]). Informal private vendors distribute water through several mechanisms: half-litre plastic sachets sold in shops and on the streets, tanker services and trucks, and 15- to 20-litre containers.

Contaminated water is a major issue in Africa as every hour an estimated 115 people die from diseases related to improper hygiene, poor sanitation or contaminated water (UN, 2015[5]). Sanitation issues are among the leading causes of disease transmission in Africa, especially for cholera, diarrhoea, dysentery and typhoid. Rapid urbanisation fairly contributes to the deterioration of water quality as cities are struggling to provide adequate wastewater infrastructure to a fast-growing population. In sub-Saharan Africa urban areas, only 20% of the population has access to safely managed sanitation and 25% to basic sanitation (WHO/UNICEF, 2019[27]). According to the World Health Organization (WHO), more than 842 000 deaths are caused each year by a lack of clean water and by poor sanitation.

Monitoring data for SDG 6.3.1 (proportion of wastewater safely treated from households) collected in 2015 are scarce but they showed that the share of wastewater from households treated is very low in sub-Saharan African countries (Niger, Senegal, Somalia and Uganda) compared to high levels in Northern African countries ( (UN-Water, n.d.[42])) (Table 1.5). In addition, the limited solid waste management in most African cities is further aggravating the situation through dirty water runoffs.

The ambient quality of water bodies is poorly monitored and only a few African countries are reporting on SDG 6.3.2 (proportion of water bodies with good ambient water quality). This situation underlines that water quality data is either missing or not readily available. This result highlights the crucial need to better monitor water quality to address effectively pollution issues.

Farming also has adverse effects on water quality. The release of important quantities of organic matter, agrochemicals and sediments, and the use of pesticides, fertilisers and excreta cause nitrates and phosphates to infiltrate water bodies leading to eutrophication. Pollution through sediment and nutrient is closely linked to land use changes and practices. In West Africa, deforestation reduced tropical rainfall and affected wildlife, weather patterns and ecosystems. It caused soil erosion, generating more sediment into nearby water bodies. The potential impacts of unchecked land development are expected to increase in the future, with Africa expected to experience the greatest expansion of cropland globally by 2050.

Emerging pollution issues are likely to substantially increase the needs and costs of wastewater management, in particular in urban environments. These include improvement of individual and other appropriate sanitation systems, combined sewers and risks of overflows, contaminants of emerging concern (such as micro-plastic) or sludge management.

Africa is the second-driest continent in the world after Australia. About two-thirds of its territory is arid or semi-arid and more than one-third of the sub-Saharan African population live in a water-scarce environment – with less than 1 000 m3 per capita per year (UN, 2014[44]). It is estimated that by 2030, 75 to 250 million people in Africa will be living in areas of high water stress, which will likely displace from 24 to 700 million people as living conditions will become increasingly unliveable (Climat, environnement, société, 2012[45]).

Evapotranspiration associated with rising temperatures is likely to increase drought frequencies, as they may cancel out precipitation projected increases in some areas of the continent. For example, in Eastern and Southern Africa, droughts are projected to intensify due to evapotranspiration and precipitation changes (Niang et al., 2014[46]) and will continue to contribute to water scarcity. This finding is further confirmed by the fact that many African countries are considered on a high or extremely high baseline water stress (World Resources Institute, 2019[47]). Among them, are, for instance, Botswana, Namibia or Djibouti (Table 1.6).

The consequences of droughts are manifold. In 2019, failed rains across Eastern Africa, Southern Africa and the Horn of Africa increased food prices and drove up the aid needs of more than 45 million people struggling to find enough food across 14 countries. This same year, in Southern Africa alone, according to the International Federation of Red Cross and Red Crescent Societies (IFRC), at least 11 million people faced food shortages due to drought. Diminished and late rainfall, combined with long-term increases in temperatures, have jeopardised the food security and energy supplies in the region, most acutely in Zambia and Zimbabwe. Grain production was down 30% across the region and 53% in Zimbabwe. Livestock farmers in Southern Africa have also suffered losses due to starvation and to early culling of herds forced by shortages of water and feed. In Kenya, water scarcity induces rural to urban migration, thus increasing pressure on already insufficient urban water supplies (Kinuthia-Njenga, 2009[48]). In Mombasa, Kenya, a drought caused an increase in food prices, disproportionately affecting the urban poor (Awuor, Orindi and Adwera, 2008[49]). In Lusaka, Zambia, following a drought year, urban agricultural output was significantly reduced, thus undermining household food security and income (Simatele, Binns and Simatele, 2012[50]). These examples highlight the various economic, social and health implications of droughts. They also underline the vulnerability of African cities to such water risks.

In 2015, the city of Cape Town started experiencing drought and water reservoirs further reached critically low levels in 2017 and in 2018. The intense hydrological drought attributable to the effects of climate change was exacerbated by anthropic factors such as rising urban population and regional competition among local water users, all placing enormous stress on limited resources. The 16 April 2018 was postulated to be the day that Cape Town switched off its taps. Colloquially termed “Day Zero”, this was defined as the point at which the dam levels fell to 13.5%, therefore requiring all taps in the city of Cape Town to be shut off and citizens to fetch a daily 25 litres per person at public points of distribution (PODs). Although Day Zero did not happen, the Cape Town water crisis exposed a serious vulnerability to water scarcity issues for the city of Cape Town, the surrounding urban agglomerations and the country at large. Water scarcity issues put greater pressure on the rural-urban interdependent relationship. The 2015-18 drought had a significant impact on agriculture, livelihoods and communities, with an estimated economic loss of ZAR 5.9 billion (USD 0.4 billion) for agriculture in the Western Cape alone, 30 000 job losses and 13%-20% exports drop (World Wildlife Fund, 2018[51]). Tourism accounts for 10% of South Africa’s economic output and provides 1.5 million jobs – around 10% of total employment in the country (Parks, 2019[52]).

Around the world, a number of economic, social and environmental trends are generating major disruptions now and in the future, and challenging public policies at all levels. The most significant of these are considered megatrends, as they are large in scale and long-term in nature – usually relevant for at least two decades. Consequently, megatrends usually refer to circumstances that will unfold across the globe in a number of countries and that can often drive the global economy and society in specific directions. Megatrends are likely to result in meaningful, long-term changes impacting social, economic, political, environmental and technological issues. Despite their potential for high impact, they often unfold slowly and follow relatively stable trajectories.

In African countries and cities, some of these megatrends significantly affect water security, as is the case of climate change, urbanisation and population growth. Climate change is also exacerbating the pressure on water resources with two-thirds of African cities estimated at “extreme risk” with regard to climate change impacts. For instance, in sub-Saharan Africa, the cumulative effect of the last decades indicates that floods and droughts alone are responsible for around 80% of disaster-related deaths and 70% of economic losses (Ndaruzaniye et al., 2010[7]). With 41% of the sub-Saharan African population currently living in cities, and a projected increase to 60% by 2050 (UN, 2015[5]), urbanisation will exacerbate existing challenges related to access to quality drinking water and sanitation services. And last but not least, demographic trends are pushing water demand up (Figure 1.4) with African urban population projected to nearly double from more than 560 million in 2015 to 1.1 billion in 2050 (UN, 2014[44]).

When asked about the most influential megatrends at the local level, respondent African cities to the OECD Survey on Water Governance (Annexes A and B) declare that climate, urbanisation and demographic changes, are on the megatrends that mostly affect water security (Table 1.7). Other megatrends also affect water resources and services, such as poverty alleviation, economic growth and food insecurity, although to a lesser extent.

According to the Intergovernmental Panel on Climate Change (IPCC), Africa is among the most vulnerable continents to climate change, which affects water security in many ways since the vast majority of climate change impact is felt in the water sector. “Near surface temperatures have increased by 0.5°C or more during the last 50 to 100 years over most parts of Africa, with minimum temperatures warming more rapidly than maximum temperatures” (Niang et al., 2014, p. 1206[46]). Projected temperatures in Africa will rise faster than the global average throughout the 21st century, thus reinforcing water scarcity and drought risks. Pressure on already limited water supply is expected to increase sharply due to changes in water cycles caused by erratic rainfall and to affect negatively the production of annual crops such as cereals and cotton, or perennial crops like coffee, cocoa and palm oil. This will lead to production shocks that will worsen food insecurity. Livestock may also suffer from the shrinking water supply, as grazing land is divided and damaged. Researchers estimate that climate change and climate hazards (Figure 1.5) will depress growth in global yields by 5% to 30% by 2050 (Porter et al., 2013[54]).

The Climate Change Vulnerability Index (CCVI),2 which assesses the capacity of cities to withstand climate shocks, shows that two-thirds of African cities are at “extreme” risk, due to rising populations and poor urban infrastructure. The vulnerability is also driven by various factors including weak adaptive capacity, high dependence on ecosystem goods for livelihoods and less developed agricultural production systems. For instance, the city of Kinshasa, Democratic Republic of the Congo, which counts 13 million inhabitants, is exposed to weather shocks, including flooding, as well as droughts in surrounding areas, which could drag poor farmers into the city while disrupting water and food supplies. Along with other African cities, Kinshasa remains at high risk with cumulating factors of high poverty rates, expanding slums, weak governance and limited capacity to adapt to climate change. Its increasing urban population which is expected to double by 2035, will very likely intensify the city’s already alarming risk profile in terms of access to drinking water or habitat. Among other cities most at risk of climate change are: Kampala, Uganda, where the annual population is set to grow by 5.1% a year on average between 2018-35; Dar-es-Salaam in Tanzania (4.8%); Abuja (4.5%) and Lagos (3.5%) in Nigeria; Addis Ababa (4.3%) in Ethiopia; and Luanda (3.7%) in Angola.

Africapolis data highlight the staggering pace of the ongoing urbanisation transformation in Africa. Fifty percent of Africa’s population live in one of the continent’s 7 617 urban agglomerations. In 9 countries, the level of urbanisation is above 66% and a further 30 countries have an intermediary level of urbanisation between 33% and 65%. In 1950, only 4 countries had a level of urbanisation above 33%, while 35 countries were below 10%. North Africa is the continent’s most urbanised region (78%), and Egypt and Libya the 2 countries with the highest levels of urbanisation with 93% and 81% respectively (Figure 1.6). The other 2 countries with a level of urbanisation above 80% are Gabon (81%) and São Tomé and Príncipe (80%). The countries with the lowest levels are Niger (17%), Burundi (21%), Eritrea (24%), Lesotho (26%) and South Sudan (27%).

Overall, countries with higher income levels in the African continent tend to have higher urbanisation levels. The only two low-income countries (gross national income per capita) with a level of urbanisation above 50% are Rwanda, with the highest population density, and Gambia, one of the smallest land areas. Similarly, the countries with the highest levels of urbanisation, Djibouti, Egypt, Gabon and Libya, are all middle-income countries and countries whose land areas are almost entirely desertic or with large forest areas, like Gabon. In these countries, the share of the agricultural population – the main activity of the rural population – is rather low.

Urbanisation dynamics are influenced by a variety of structural and socio-economic factors, such as geography and climate, population growth, size and density, income levels and economic structure, policies and institutions and cyclical factors such as environmental disasters, conflict and economic cycles. These factors are not of equal importance and vary over time depending on country contexts and interrelations. Since the 1990s, the major driver of urbanisation has been high population growth which contributes directly to the natural increase of urban populations.

This urban population growth in Africa is mostly absorbed by the outward expansion of metropolitan areas and secondary cities. As such, African cities are sprawling extensively, which exacerbates the spatial concentration of economic, environmental and social problems (World Resources Institute, 2019[47]) and holds significant implications for water supply and demand. Between now and 2050, two thirds of the urbanisation will happen in towns and intermediary cities (AfDB/OECD/UNDP, 2016[56]), which have less capacities to deploy infrastructure than larger cities. Because of this urban expansion pattern, African cities suffer from a lack of adequate formal housing and access to basic local public services, both in the informal settlements of the urban centre but also in the periphery. Indeed, densely populated informal settlements lack proper urban infrastructure. In most African cities, population and economic density is higher near the city centre and falls by 7% one kilometre away from the city centre, compared to 4% on average in other cities around the world. Night light intensity also falls by 15%, compared with 11% in cities elsewhere (Vinay, 2017[29]). This development pattern already poses many challenges in terms of planning, housing and basic infrastructure, and public services provision, among others. This is reflected in the heterogeneous development of planned and unplanned urban areas, the latter comprising informal settlements and peri-urban areas falling outside of the formal urban boundary and having rural and urban characteristics (Owusu, Agyei-Mensah and Lund, 2008[57]).

Urban growth in sub-Saharan African cities occurs predominantly in unplanned and informal settlements: 56% of urban dwellers in Africa live in these areas, compared to one-third in developing countries in general (UN, 2015[5]). Despite a slight decline of urban population living in slums over the past three decades, in some capital cities, informal settlements absorb the largest share of urban growth (Figure 1.7).

Unmanaged urban land expansion and sprawling, which are primarily driven by population growth, also have adverse effects on land use and the environment. Increasing conversion of surrounding agricultural land and water bodies has strong impacts on food production, habitats and biodiversity conservation. Increased urban sprawl also means increased greenhouse gas emissions, air pollution and urban heat. Recent projections foresee that in mid-latitudinal Africa, urban areas are expected to increase by nearly 20-fold by 2030 compared with a 2000 baseline, with the largest forecasted increase in the vicinity of environmentally protected areas (Güneralp et al., 2017[59]).

For the past decades, Africa has witnessed a dramatic demographic increase, which is expected to continue in the future. The total population of Africa rose from 177 million in 1950 to more than 1.34 billion in 2020 (Worldometer (n.d.[60]), based on UN estimates) which represents 16.2% of the world’s population. Despite a decline in fertility rates in most sub-Saharan African countries, which still remain the highest in the world, the population is expected to reach more than 2 billion by 2050 (UN, 2015[5]). The projected population by 2050 in Africa shows disparities among African regions. Eastern, Western and Central Africa population is expected to more than double while Northern and Southern Africa population will increase to a lesser extent (Figure 1.8).

The overall population increase in Africa was more concentrated in cities. In 2015, more than 560 million Africans lived in one of the continent’s 7 617 urban agglomerations compared to only 27 million in 1950 (Figure 1.9). When focusing on sub-Saharan African only, the urban population is projected to more than triple from 346 million to 1.1 billion by 2050 (UN, 2015[5]). Thus, urban sub-Saharan African population is estimated to grow from 41% in 2019 to 60% in 2050 (UN, 2015[5]).

The period between 1950 and 1980 saw the fastest urban growth with Africa’s urban population increasing 5.1% annually. Especially in the least urbanised regions of Central Africa, East Africa and West Africa this period was marked by very high urban growth rates, averaging between 6.4% and 8%. Between 1980 and 2000, urban growth decelerated to 4.4% for Africa as a whole and increased again to 4.7% for the period 2000-15. With a current average annual growth rate above 4%, 86 of the 100 fastest-growing cities in the world are located in Africa. Sub-Saharan African’s cities have grown at an average rate of 4% per year over the past 20 years, and are projected to grow between 3% and 4% annually from 2015 to 2055. In comparison, globally the average annual urban population growth rate is projected to range from 1.44% to 1.84% from 2015 to 2030 (WHO 2015) (Figure 1.10).

Participating African cities in the OECD Survey on Water Governance are no exception to this rapid population growth, with annual rates ranging from 2% to more than 20% over the past decade (Figure 1.11).

Although the rapid urban population increase is mainly caused by the high rate of natural increase in towns and the re-classification of hinterland settlements into urban areas, intra-regional migration also accounts for a significant proportion of urban population growth in Africa. Since 1990, African migration was predominantly intra-continental, although the distribution and migration routes changed over time. In 2000, the stock of international migrants originating from Africa and living in Africa was the main stock amounting to 12.5 million persons, highlighting that migration was foremost an intra-African phenomenon. This stock grew consistently to reach 19.4 million in 2017 (UNCTAD, 2018[62]) This intra-continental migration is significantly affecting water security as most migrants settle in urban areas, thus increasing water demand and putting further pressure on water and sanitation infrastructure.

As in many cities around the world, COVID-19 has acted as a magnifying glass on pressing water challenges, stressing and widening amongst others existing inequalities in access to water and sanitation services. Handwashing is one of the top preventive measures recommended to reduce the spread of COVID-19. However, current levels of handwashing with soap are generally low across the African continent. Monitoring handwashing behaviour is difficult but the presence of soap and water at a designated place is generally used as a proxy indicator. According to UNICEF data from 2017, the majority of Sahelian and West African people did not have basic handwashing facilities available at home. Only Ghana, Mali, Mauritania and Nigeria were above the global average of 60% of people with access to basic facilities. The situation was particularly worrisome in small countries such as Benin, Gambia, Guinea-Bissau, Liberia and Togo where at least three-quarters of the population had no handwashing facility at home. Nigeria is among the countries with the largest number of people with no access to a handwashing facility in the world (49 million), following Indonesia (78 million) and the Democratic Republic of the Congo (69 million). In urban areas in Africa, 55% of the population has access to basic sanitation services (i.e. improved sanitation facilities not shared with other households) and 47% has basic handwashing facilities at home (UN-Habitat, 2020[64]). These shares descend to 44% and 37% respectively for urban areas in sub-Saharan Africa. There are significant gaps between the richest and poorest within a country.

While rural areas are generally less well-equipped than urban areas in terms of handwashing facilities, urban populations are particularly at risk of COVID-19 contamination considering the higher population density and the large number of crowded places such as markets or public transport. In fact, over 95% of confirmed COVID-19 cases worldwide are in urban areas (UN-Habitat, 2020[64]). Public handwashing facilities are generally rare and often lack soap in African urban areas. Mobile handwashing facilities are very common in Western Africa (Figure 1.12), for example, the use of jugs or basins to wash hands before and after meals. However, mobile facilities often lack soap and sufficient water. Beyond contributing to contain the COVID-19 pandemic, washing hands is also a basic preventive measure, which can help eradicate many other communicable diseases such as cholera, which is still prevalent in the region.

In the medium term, the loss of public revenue due to the contraction of economic activity could potentially limit government investment in water and sanitation. In 2020, GDP was estimated to fall by -1% in North Africa3 and by -3.2% in sub-Saharan Africa (IMF, 2020[66]; 2020[67]). The economic slowdown has negatively affected public revenue in most sub-Saharan African countries, especially oil-exporting economies, but grants are projected to increase revenues in a few countries (Burkina Faso, Chad, Niger and Senegal). Many national governments in Africa took measures to ensure adequate water supply in response to the pandemic, with policy responses ranging from short-term subsidies or exemptions from paying water bills to more long-term plans to improve water supply and access to water and sanitation facilities. In some cases, however, both public and private longer-term investments may have been delayed or cancelled due to loss of public revenue and the economic situation.

In South Africa, while COVID-19 has hit the Western Cape Province particularly hard with 270 691 cases and 10 731 deaths (20% of total deaths in South Africa), located essentially in the city of Cape Town, the city administration has shown remarkable resilience in dealing with the pandemic, drawing extensively on lessons from past crises such as droughts (Box 1.4).


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← 1. The term informal suppliers refers to all types of water suppliers who are not operating in the legal framework of water management in an area. It refers to any form of non-utility water service and it includes all small-scale entrepreneurs that are institutionally and contractually independent of the utility. “Informal” is related both to the technical systems of provision (which may include the infrastructure and the sale of water) and the resulting relationships (Misra, K. 2014. From formal-informal to emergent formalisation: Fluidities in the production of urban waterscapes. Water Alternatives 7(1): 15-34).

← 2. The 2018 Climate Change Vulnerability Index uses some 50 existing data, ranging from climate models to economic factors, including demographic projections, to assess the vulnerability of humans to climate change and extreme weather events within a thirty-year timeframe (Verisk, Maplecroft, 2018[6]).

← 3. In IMF (2020[66]), the closest proxy to North African countries is the IMF’s Middle East, North Africa, Afghanistan and Pakistan (MENAP) region, focusing on countries that are oil importers as opposed to oil exporters (MENAP oil importers). This group of countries consists of Afghanistan, Djibouti, Egypt, Jordan, Lebanon, Mauritania, Morocco, Pakistan, Somalia, Sudan, Syria, Tunisia, and West Bank and Gaza Strip.

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