Management of Ground Water in Africa Including Transboundary Aquifers: Implications for Food Security, Livelihood and Climate Change Adaptation

Groundwater is one of the most important sources for drinking water, livestock water, and irrigation in Africa. It is of vital importance in meeting the Millennium Development Goals (MDGs) target of accessing clean water, as most of rural Africa and a considerable part of urban Africa are supplied by groundwater. Groundwater also has a major role to play in improving food security through expansion of irrigation supplied by shallow and deep wells. As such, groundwater has high relevance to the development and wellbeing of Africa, if adequately assessed and sustainably exploited. However, impacts of rapid development and climate change on water resources, including groundwater, are expected to be very severe unless major actions are taken to address the limited human and institutional capacity and hydrogeological knowledge base needed to devise sustainable adaptive water management strategies. Whilst the potential for groundwater resources development and the extent of their vulnerability due to climate change in the African context continue to be reported in the literature, a quantitative understanding of these issues remains poor. Although groundwater systems respond to human and climatic changes slowly (relative to surface water systems), climate change still could affect groundwater significantly through changes in groundwater recharge as well as groundwater storage and utilization. These changes result from changes in temperature and precipitation or from change in land use/land cover, and increased demand. There is therefore a need for ensuring sustainability and proper management of groundwater resources through instituting proper aquifer management practices such as the establishment of groundwater monitoring systems, better understanding of the role of groundwater storage and groundwater discharges in sustaining aquatic ecosystems, understanding the interactions between various aquifers (including transboundary aquifers) and assessing the impact of increased pumping from various aquifer systems on the sustainability of groundwater abstraction. This paper provides an overview of the regional hydrogeological framework, the current state of knowledge of aquifer systems, their development potential and climate change impacts on groundwater, research gaps, and policy implications for meeting the MDGs of accessing clean water and livelihood goals in Africa

Resilience in the Limpopo Basin : The potential role of the transboundary Ramotswa aquifer - Baseline report

The overall objective of the RAMOTSWA project is to support a long-term joined vision and cooperation on the shared groundwater resources of the Upper Limpopo region, where the states share significant and valuable underground freshwater resources as well as space for enhanced subsurface water storage. The project will facilitate and promote joint management and better groundwater governance focused on coordination, scientific knowledge, social redress and environmental sustainability, in order to reduce poverty and inequity, increase prosperity, and improve livelihoods and water and food security in the face of climate change and variability

Resilience in the Limpopo Basin : The potential role of the transboundary Raotswa aquifer - Final draft

As complementary report of the baseline report, this report focus on the hydrogeological assessment of the Ramotswa Transboundary Aquifer and covers only aspects related to the biophysical conditions of the aquifer which is a karstic dolomit aquife straddling the international border between Botswana and South Africa. The assessment is based on existing data and field data collected (including Airborne Electro-Magnetic survey) during the period September 2015 –November 2016. The technical knowledge developed in the report will be used as based for developing tools for harmonized management and fostering crossborder dialogue in order to help building the joint Strategic Action Programme which will provide, not exclusively, guidelines for better monitoring and future assessment of the aquifer

Cartographie du potentiel de développement de l'irrigation durable avec des eaux souterraines renouvelables en Afrique pour réduire l'insécurité alimentaire africaine

In Africa, groundwater irrigation is considered a reliable and affordable means to increase food security. Areas equipped for groundwater irrigation in Africa have however, developed slowly since 1950 and remain very limited. To date, no studies have identified the sustainable development potential of irrigation with renewable groundwater across Africa. This study is based on two approaches to locate and quantify this potential. The quantitative hydrological approach is based on the estimation of the current crop irrigation need and available renewable groundwater for irrigation after all other water needs, including environmental, have been satisfied. This approach shows that the potential is 44.6 x 106 ha or 20.5% of the cropland over the continent. The environmental approach redefines the quantitative potential by considering a set of biophysical and socio-economic factors conducive to sustainable development of groundwater irrigation. The potential is then 19.3 x 106 ha and it is reduced mainly from the equatorial regions where the need for irrigation is limited. In fact, without considering the countries of the Maghreb and South Africa where current irrigation by groundwater exceeds the estimated potential, groundwater irrigated areas could be multiplied by 75. The largest areas which are worthwhile to develop are mainly located along a west-east line from Angola to the north of Mozambique and a line south of the Sahel. The dry regions of the Sahel, East Africa and Southern Africa have limited development potential which is more suitable to small-scale agriculture and could greatly improve food security in Africa.En Afrique, l'irrigation des cultures par les eaux souterraines est considérée comme un outil fiable et abordable pour augmenter la sécurité alimentaire mais les superficies équipées pour l'irrigation par les eaux souterraines restent très limitées. Cette étude se base sur deux approches pour localiser et quantifier le potentiel de développement de l’irrigation des cultures par les eaux souterraines renouvelables sur l'ensemble du continent. L’approche quantitative et hydrologique s’appuie sur l’estimation des eaux souterraines renouvelables disponibles après satisfaction de tous les autres besoins, y compris environnementaux et sur le besoin en irrigation des cultures et montre un potentiel s’élevant à 44.6 x 106 ha soit 20.5% des cultures du continent. L’approche contextuelle redéfinit le potentiel quantitatif en considérant un ensemble de facteurs biophysiques et socio-économiques propices au développement de l’irrigation par les eaux souterraines. Le potentiel s’élève alors à 19,3 x 106 ha et est réduit essentiellement dans les régions équatoriales où le besoin en irrigation est limité. En fait, sans considérer les pays où l’irrigation actuelle par les eaux souterraines excède le potentiel estimé, les surfaces irriguées pourraient être multipliées par 75. Les plus grandes surfaces propices au développement de l'irrigation sont principalement situées le long d’une ligne ouest-est de de l’Angola au nord du Mozambique et d’une ligne au sud du Sahel. Les régions sèches du Sahel et de l’Afrique de l’Est et australe ont un potentiel de développement plus limité, plus adapté à la petite agriculture, qui pourrait améliorer amplement la sécurité alimentaire en Afrique

Cartographie du potentiel de développement de l'irrigation durable avec des eaux souterraines renouvelables en Afrique pour réduire l'insécurité alimentaire africaine

In Africa, groundwater irrigation is considered a reliable and affordable means to increase food security. Areas equipped for groundwater irrigation in Africa have however, developed slowly since 1950 and remain very limited. To date, no studies have identified the sustainable development potential of irrigation with renewable groundwater across Africa. This study is based on two approaches to locate and quantify this potential. The quantitative hydrological approach is based on the estimation of the current crop irrigation need and available renewable groundwater for irrigation after all other water needs, including environmental, have been satisfied. This approach shows that the potential is 44.6 x 106 ha or 20.5% of the cropland over the continent. The environmental approach redefines the quantitative potential by considering a set of biophysical and socio-economic factors conducive to sustainable development of groundwater irrigation. The potential is then 19.3 x 106 ha and it is reduced mainly from the equatorial regions where the need for irrigation is limited. In fact, without considering the countries of the Maghreb and South Africa where current irrigation by groundwater exceeds the estimated potential, groundwater irrigated areas could be multiplied by 75. The largest areas which are worthwhile to develop are mainly located along a west-east line from Angola to the north of Mozambique and a line south of the Sahel. The dry regions of the Sahel, East Africa and Southern Africa have limited development potential which is more suitable to small-scale agriculture and could greatly improve food security in Africa.En Afrique, l'irrigation des cultures par les eaux souterraines est considérée comme un outil fiable et abordable pour augmenter la sécurité alimentaire mais les superficies équipées pour l'irrigation par les eaux souterraines restent très limitées. Cette étude se base sur deux approches pour localiser et quantifier le potentiel de développement de l’irrigation des cultures par les eaux souterraines renouvelables sur l'ensemble du continent. L’approche quantitative et hydrologique s’appuie sur l’estimation des eaux souterraines renouvelables disponibles après satisfaction de tous les autres besoins, y compris environnementaux et sur le besoin en irrigation des cultures et montre un potentiel s’élevant à 44.6 x 106 ha soit 20.5% des cultures du continent. L’approche contextuelle redéfinit le potentiel quantitatif en considérant un ensemble de facteurs biophysiques et socio-économiques propices au développement de l’irrigation par les eaux souterraines. Le potentiel s’élève alors à 19,3 x 106 ha et est réduit essentiellement dans les régions équatoriales où le besoin en irrigation est limité. En fait, sans considérer les pays où l’irrigation actuelle par les eaux souterraines excède le potentiel estimé, les surfaces irriguées pourraient être multipliées par 75. Les plus grandes surfaces propices au développement de l'irrigation sont principalement situées le long d’une ligne ouest-est de de l’Angola au nord du Mozambique et d’une ligne au sud du Sahel. Les régions sèches du Sahel et de l’Afrique de l’Est et australe ont un potentiel de développement plus limité, plus adapté à la petite agriculture, qui pourrait améliorer amplement la sécurité alimentaire en Afrique

Water resource management in the Olifants Basin of South Africa: previous projects and future prospects

Paper presented at the 1st Sub Saharan Africa HELP Basin Workshop, Johannesburg, South Africa, 23-25 November 2011The Olifants River Basin is located in the north-eastern part of the South Africa and southern to Mozambique.The Olifants River passes through three provinces of South Africa (Gauteng, Mpumalanga, Limpopo Province), through the Kruger National Park, into Mozambique, where it joins the Limpopo . it is the home to nearly 10 % of the total population of South Africa. The climate is semi-arid, with rain falling primarily during the summer (November to March). Precipitation averages 630 mm and potential evaporation is 1700mm. In South Africa, significant mining, industrial and agricultural activities (including intensive irrigation schemes) are concentrated within the catchment, so it is of considerable importance for the country's economy. However, Water is especially scarce in this basin. Like many river basins in South Africa, water resources in the Olifants river basin are almost fully allocated. Water demand management, especially in the agricultural sector, which is the biggest user, is one of the possible solutions being considered by the South African Department of Water Affairs and Forestry (DWAF). The basin also faces significant water quality problems, due to mining activities, industries, power generation and agricultural use of water. The impact of these pollutions (high salinity, high concentrations of metals, low pH) are probably multiple with serious ecological impacts. Particularly of concern in the downstream Kruger National Park which is a major tourist attraction in South Africa and more importantly very worrisome health impacts, since some people are drinking surface water without any treatment. In South Africa it is of prime importance to maintain a minimum level of water quality and quantity in the rivers in order to maintain a healthy biophysical environment (DWAF, 1997). This requirement, referred to as the 'Ecological Reserve', is as important in the South African legislation as meeting the basic human needs and must be met before any other users can abstract water. Main activities on the Olifants basin have been done through the Challenge Program on Water and Food and the WETwin project but not only

Transboundary aquifer mapping and management in Africa: a harmonised approach

Recent attention to transboundary aquifers (TBAs) in Africa reflects the growing importance of these resources for development in the continent. However, relatively little research on these aquifers and their best management strategies has been published. This report recapitulates progress on mapping and management frameworks for TBAs in Africa. The world map on transboundary aquifers presented at the 6th World Water Forum in 2012 identified 71 TBA systems in Africa. This report presents an updated African TBA map including 80 shared aquifers and aquifer systems superimposed on 63 international river basins. Furthermore, it proposes a new nomenclature for the mapping based on three sub-regions, reflecting the leading regional development communities. The map shows that TBAs represent approximately 42 % of the continental area and 30 % of the population. Finally, a brief review of current international law, specific bi- or multilateral treaties, and TBA management practice in Africa reveals little documented international conflicts over TBAs. The existing or upcoming international river and lake basin organisations offer a harmonised institutional base for TBA management while alternative or supportive models involving the regional development communities are also required. The proposed map and geographical classification scheme for TBAs facilitates identification of options for joint institutional setups

Availability and use of water resources

Peer Revie

Will the European Regulation for water reuse for agricultural irrigation foster this practice in the European Union?

International audienceThe development of the water reuse sector within the European Union (EU) varies considerably. In 2020, Portugal, Spain, Italy, Greece, France and Cyprus had the most comprehensive regulations for the reuse of reclaimed water for agriculture. The approval of a common regulation by the EU Parliament and the Council in May 2020 (which came into effect in June 2023) elicits the question of how each country will comply with it. This review compares (i) national regulations to the 2020 European Regulation, (ii) existing projects with respect to their performance in terms of water quality and (iii) raises a debate about the role of the EU Regulation in fostering water reuse at the EU level. The European Regulation will probably strengthen consumer confidence as common minimum requirements are now required. However, the issues related to micropollutants, disinfection by-products or possible changes in the water quality downstream of the compliance point are not fully considered by the EU Regulation. Moreover, other techno-economic obstacles to be overcome include the distance between the production of treated water and agricultural needs, the low economic competitiveness of reclaimed water and the implementation of the multi-barrier approach