Groundwater In Africa Research Articles

Some Legal Options to Ensure the Protection of South Africa's Utilisable Groundwater Resources

Groundwater, which is water that is found underground, is less susceptible than surface water resources to evaporation, and thus offers resilience against the impacts of climate change. Many South African cities, communities and farmers depend on groundwater for domestic or other socio-economic purposes. This implies that groundwater resources which are currently or potentially utilisable should be identified, and suitable legal measures should be implemented to protect these resources from potential risks of harm or damage posed by anthropogenic activity. This article firstly evaluates the effectiveness of the country's existing regulatory framework to effectively protect South Africa's groundwater resources and finds that the framework can be improved upon significantly. Secondly, it explores regulatory opportunities within the existing legal framework to strengthen South Africa's groundwater governance regime, including making use of land-use planning instruments to facilitate the implementation of groundwater protection zones.

Assessing groundwater salinity across Africa

In Africa groundwater is the principal source of drinking water (https://washdata.org/) and has significant potential to improve food production as a source of irrigation water. Although volumes of stored groundwater are high when compared to surface water, not all the available groundwater is suitable for irrigation. One of the principal factors that limit the development of groundwater is salinity, but quantitative evidence regarding the scale of salinization in Africa has been lacking. This paper presents an initial analysis of the extent of groundwater salinization in Africa, bringing together groundwater salinity data (n = 12,255) from across the continent. In our dataset c.80% of the samples have electrical conductivity values less than 2000 μS/cm. Samples with high conductivity values of more than 2000 μS/cm are restricted to limited geological and climatic environments. The data reveals salinity does not affect the water security status of most countries in Africa. However, salinity compounds water insecurity issues in arid low groundwater recharge environments. The paper discusses the role of anthropogenic processes such as river valley water resources development, extensive groundwater pumping, inter-basin groundwater transfer, and irrigation in altering the salinity of groundwater bodies. The paper further elucidates the origin of groundwater salinity by critically reviewing the natural and human-induced factors that control the salinization of the various groundwater bodies across Africa. Existing case studies reveal several causes of salinization, including i) human-induced salinization, ii) climate and hydrological change-induced paleo groundwater salinity, iii) rock dissolution, and iv), saltwater encroachment.

Fluoride Levels in Surface and Groundwater in Africa: A Review

Fluoride has been reported to be among natural pollutant of water in Africa. High fluoride levels beyond the recommended World Health Organization limit of 1.5 mg/l has been observed in various Africa countries. However, the information is scattered in different publication medium. Therefore, objective of this work was to put together the information on fluoride levels in surface and groundwater in Africa, and describe the status and distribution of fluoride in water among African countries. This study assembled the secondary data of fluoride concentrations in surface and groundwater from the various literatures in African countries. Such countries represent southern, northern, eastern and western Africa. Descriptive statistics was used and results showed that elevated fluoride concentration occurred in countries such as Tanzania, Kenya, Algeria, Nigeria, Ghana, Malawi, Sudan, Uganda, the Republic of South Africa and Ethiopia. The highest fluoride concentration reported was 2,800 mg/l in Lake Nakuru in Kenya. The high fluoride concentrations in water can be linked to volcanic activities, presence of thermal waters especially those with high pH, gases emitted from earth’s crust, granitic and gneissic rocks. The high fluoride in water is severe in countries located in East African Rift Valley like Kenya, Tanzania and Ethiopia. However, all the incidences of highest fluoride levels in water in the Rift Valley countries were found in surface water bodies. This is contrary, as it is expected groundwater to be more concentrated as compared to surface water due to more water rock interaction than in surface water bodies. There was no single study among many studies has reported the long term trend of concentration of fluoride in water with time. Thus, the effort to establish long term trend of fluoride concentration in water should be taken in consideration. This helps to predict future concentration of fluoride and possibility to minimize future risks. Also, fluorosis has also been reported to be endemic in fluoritic areas of Africa though, little is known on other fluoride negative effects. Therefore, more efforts should concentrate on finding appropriate defluoridation techniques to be applied while considering the cost of operation, efficiency, practicability, easy application and environmental friendly.

Mapping irrigation potential from renewable groundwater in Africa – a quantitative hydrological approach

Abstract. Groundwater provides an important buffer to climate variability in Africa. Yet, groundwater irrigation contributes only a relatively small share of cultivated land, approximately 1% (about 2 × 106 hectares) as compared to 14% in Asia. While groundwater is over-exploited for irrigation in many parts in Asia, previous assessments indicate an underutilized potential in parts of Africa. As opposed to previous country-based estimates, this paper derives a continent-wide, distributed (0.5° spatial resolution) map of groundwater irrigation potential, indicated in terms of fractions of cropland potentially irrigable with renewable groundwater. The method builds on an annual groundwater balance approach using 41 years of hydrological data, allocating only that fraction of groundwater recharge that is in excess after satisfying other present human needs and environmental requirements, while disregarding socio-economic and physical constraints in access to the resource. Due to high uncertainty of groundwater environmental needs, three scenarios, leaving 30, 50 and 70% of recharge for the environment, were implemented. Current dominating crops and cropping rotations and associated irrigation requirements in a zonal approach were applied in order to convert recharge excess to potential irrigated cropland. Results show an inhomogeneously distributed groundwater irrigation potential across the continent, even within individual countries, mainly reflecting recharge patterns and presence or absence of cultivated cropland. Results further show that average annual renewable groundwater availability for irrigation ranges from 692 to 1644 km3 depending on scenario. The total area of cropland irrigable with renewable groundwater ranges from 44.6 to 105.3 × 106 ha, corresponding to 20.5 to 48.6% of the cropland over the continent. In particular, significant potential exists in the semi-arid Sahel and eastern African regions which could support poverty alleviation if developed sustainably and equitably. The map is a first assessment that needs to be complimented with assessment of other factors, e.g. hydrogeological conditions, groundwater accessibility, soils, and socio-economic factors as well as more local assessments.

Groundwater renewable resource versus demand: ‘good news’ or ‘bad news’ for rural communities?

Government water authorities and aid agencies are receiving conflicting messages about groundwater availability in sub-Saharan Africa. ‘Good news’ articles suggest that groundwater is available in abundance. ‘Bad news’ articles report water-point failure caused by depletion of groundwater storage rather than the more widely recognized mechanical failure of pump or borehole structure. These contradictory messages need to be read in the perspective of the scale of the assessment being described. Although there is plenty of groundwater in Africa, it is neither evenly distributed nor universally accessible. There are places where the groundwater resource renewal cannot keep pace with demographic stress and the local aquifer is drying up; groundwater in Africa is not just a water supply issue but has also become a complex management, maintenance, and regulatory problem. Lessons need to be learnt, not least with regard to the sustainable achievement of the Millennium Development Goals; the key lesson is that government and aid agencies need to recognize that groundwater is a finite resource of limited capacity.

Random Sample

Researchers are holding a bake sale to raise awareness of potential budget cuts and how they might affect planetary research. A Greenlandic graphic artist and a group of Danish archaeologists and self-confessed "cartoon nerds" have created a series of action-packed graphic novels on the prehistory of Greenland, from the peopling of the island 4500 years ago to the shamanic traditions of later Dorset culture hunters. And this week's numbers quantify the total volume of groundwater in Africa and deaths if a magnitude-7.3 earthquake strikes Tokyo.

Foreword to Special Section: Groundwater in Africa

Foreword to Special Section: Groundwater in Africa

Climate change, population trends and groundwater in Africa

Global climate change is affecting Africa, as it is every other continent and region of the world. The absolute poverty of a large proportion of the continent's people renders them highly vulnerable to changes in climate. Mitigation of climate change is a global imperative. However, numerous other changes continue apace, notably population growth, natural resource degradation, and rural—urban migration. Probably 50% or more of the continent's population rely on groundwater. This paper explores the relative impacts of changes in climate, demography and land use/cover on groundwater resources and demands. It concludes that the climate change impacts are likely to be significant, though uncertain in direction and magnitude, while the direct and indirect impacts of demographic change on both water resources and water demand are not only known with far greater certainty, but are also likely to be much larger. The combined effects of urban population growth, rising food demands and energy costs, and consequent demand for fresh water represent real cause for alarm, and these dwarf the likely impacts of climate change on groundwater resources, at least over the first half of the 21st century.

Cooperation on Africa's transboundary aquifers—conceptual ideas

As many of Africa's groundwater resources are stored in approximately 40 transboundary aquifer systems, cross-boundary coordination will become imperative if this potential is to be developed. A research and consultancy project has investigated the stages of cooperation on Africa's transboundary aquifer systems and considered whether national utilisation patterns are already causing negative transboundary impacts on riparian states. While most overuse and negative effects have so far been contained at local level, development plans are potential threats. The research project assumed that the identification of typical riparian constellations based on hydrogeological, geopolitical, social and economic features could contribute to an understanding of the transboundary implications of national usage and thus of the basis on which to develop management. The typology developed by Eckstein & Eckstein was used and refined for the analysis. However, it seems that transboundary aquifer systems defy simplification and do not allow typical riparian constellations to be identified. Owing to the major uncertainties encountered, it is not trivial to state that improving the knowledge base for management is of the utmost importance.

Can Groundwater Meet Africa's Demand for Water as Climates Change?: Groundwater and Climate in Africa: An International Conference; Kampala, Uganda, 24–28 June 2008

The impact of climate variability and change on groundwater resources remains poorly understood and is one of the most persistent knowledge gaps identified by the Intergovernmental Panel on Climate Change (IPCC) in both its Third (2001) and Fourth (2007) Assessment Reports. The common exclusion of groundwater from current monitoring and evaluation of the impacts of climate variability and change is of particular concern in Africa, where approximately half of its nearly 1 billion inhabitants rely upon groundwater for their daily water supply. Furthermore, future adaptations in response to climate change and rapid population growth are expected to intensify dependence upon ground water in Africa as communities seek to improve access to safe water and adequate sanitation pursuant to the U.N. Millennium Development Goals, which include sustaining food security and promoting agricultural and industrial development.

Editor’s message: building capacity and partnerships towards sustainable utilization of groundwater in Africa

Editor’s message: building capacity and partnerships towards sustainable utilization of groundwater in Africa