Applied Groundwater Studies in Africa

Hydrogeology Journal

Poverty reduction and economic growth drive the development of groundwater resources across Africa. Due to the ephemeral nature of surface water, groundwater abstraction is often the only realistic and affordable means of providing reliable water supply for much of Africa's needs. However, the large variability in geological and hydrological conditions have a profound influence on the availability of groundwater across the continent, and the sustainable development of the resource depends on an accurate understanding of the hydrogeology and the availability of skilled people to make informed decisions. Despite the obvious need for data, little attention has been paid to the systematic gathering of information about groundwater resources, with the result that data are patchy, knowledge is limited and investment is often poorly targeted. Given the scale of groundwater development in Africa, there is now a pressing need to take groundwater resources seriously and provide a framework and funds for applied groundwater research across Africa to underpin current and future development and management of this precious resource. This framework must recognise the issues of particular concern to Africa, such as: the requirement to develop sustainable and cost effective community water supplies across all hydrogeological environments (even challenging ones); appropriately managing and protecting groundwater resources given the rate of rapid poorly planned urbanisation and the expansion in on-site sanitation and; the imperatives of water security, from household to national levels, with unpredictability of future climate, groundwater recharge and water demand.

Groundwater is Africa’s most precious natural resource, providing reliable water supplies to many people, and the potential to supply many more. However, sustainable groundwater development is not a trivial task. It depends critically on an understanding of the hydrogeology and skilled people to make informed decisions on how best to develop and manage groundwater. Scant attention has been paid to the systematic gathering of information on groundwater resources in the past few decades, with the result that data are patchy, knowledge is limited and investment is often poorly targeted. This book begins the process of bridging the knowledge gap. The 29 chapters were written both by practitioners and researchers (mainly from within Africa) based on experience from recent and ongoing projects. The book highlights the variety and complexity of issues surrounding the development and management of groundwater resources across Africa, and provides a snapshot of groundwater research in the early 21st century. The book will inform practitioners within Africa as well as the wider international community that are working towards better water coverage in Africa and elsewhere.

… , DC: Woodrow Wilson …, 2006

It is impossible to understand the developmental constraints of Africa without grasping the significance of water resources, particularly groundwater. Southern Africa1 faces poten-tially severe groundwater shortages, which not only imperil the lives of those directly dependent on it, but also the ...

The Iullemmeden Basin, ϳ620,000 km 2 in area, is the fourth largest transboundary sedimentary aquifer in sub-Saharan Africa. In its southern part, the unconfi ned aquifers of the Continental Terminal and Continental Hamadien are recharged by focused infi ltration through ponds and gullies. A long-term rise in the water table of ϳ4 m (1963-2007) was shown to have occurred in response to land clearing over ϳ10,000 km 2 in the southwestern part of the basin. This paper presents new evidence that a long-term rise of up to 0.4 m/a have also occurred over Ն100,000 km 2 during various time periods through the 1950s to the 2000s in response to land clearing. This represents one of the longest periods (ϳ60 years) and the largest surface area at the global scale showing a rise in the water table. Increased pumping would be needed to avoid soil salinization in valleys where the water table is now increasingly outcropping. Irrigation using groundwater ("blue" water) will also help to mitigate the impacts of rainfall variability on rain-fed crop production.

International Journal of Geography and Geology, 2021

Groundwater resources of the Cretaceous Gundumi Formation and the underlying crystalline basement rocks have always been the source of water supply in Daura. Records of thirty-one boreholes drilled in the area between 1959 and 1996 were reviewed to deduce the hydrogeology of the area. The lithology of the study area obtained from strata logs and geophysical survey comprises decomposed crystalline rocks overlain by basal conglomerate, loosely cemented gravely sandstone, ferruginous sandstone and clay horizons, capped in places by laterite or silty fine sands. The area is divided into the northern and southern wellfields with average thicknesses of the Gundumi Formation of 50 m and 35 m, respectively. The average yield of the productive boreholes is 4.1 lps. The aquifer of the Gundumi Formation in the Daura area has low to moderate groundwater potential. However, the low capacities of the production boreholes are adequate to sustain the domestic water requirements of the population. Borehole site selection should be based on geophysical investigation, while the drilling rig should be capable of both rotary and downhole-hammer drilling. The borehole completion materials should be resistant to corrosion because of the low pH of the groundwater. The quality of the groundwater is generally suitable for domestic uses, though aeration or lime treatment may be necessary in some cases because of the slightly acidic nature of the groundwater. Contribution/Originality: This study is one of the very few studies which have investigated the aquifer properties, groundwater potential and quality in the Daura area of Katsina State, Nigeria using geophysical, borehole and physicochemical data, in a view to appraise the groundwater resources, improve borehole siting, construction and development in the area. the chemical composition is within tolerable limits (Offodile, 1992). In order to meet the domestic, agricultural and industrial needs of the people, the search for potable water has often been extended into the subsurface.

Groundwater plays a vital role in both human life and ecosystem. All over the world, industrial development, agriculture and human existence and health depend on the availability of good quality water in sufficient quantity. In Africa groundwater is a critical resource: Nearly 80% of the continent’s population uses groundwater as its main source of drinking water – but in many parts of the region reaching basic water requirements for health is still of concern. This is reflected by the high Human Poverty Index, which is a function of access to adequate and potable water. There is considerable progress towards the Millennium Development Goals (MDGs) in Africa with regard to meeting basic water and sanitation needs; thus, the effects on human health face a downward trend. However, records of health cases relating to consumption of groundwater in some part of Africa calls for increased attention if the MDGs are to be achieved. In this chapter, cases of groundwater quality, particularly drinking water supply, have been reviewed in relation to human health. Case histories are taken mainly from West–Central Africa and East Africa to illustrate the fact that there are unmet needs in health traceable to groundwater quality and inadequacies in water supply.

Hydrological Sciences Journal, 2013

An investigation on the groundwater potentials of the Egbe-Mopa area in central Nigeria, underlain by the Basement Complex, is presented. The investigation involved mapping of the subsurface by use of vertical electrical soundings; measurement of depth to groundwater; and evaluation of hydraulic conductivity, transmissivity and yield by means of pumping test interpretation. The results indicate subsurface units that range from three to five resistivity layers; depth to groundwater of 0-10 m; overburden thickness of 3-16 m; hydraulic conductivity of 6.2 × 10-6 to 3.4 × 10-4 m/s; transmissivity of 4.3 × 10-7 to 2 × 10-3 m 2 /s; and groundwater yield of 0.2-2.5 L/s. The hydraulic head assessments revealed a general northward groundwater flow direction. The study identified three aquifer potential types, of high, medium and low productivity, respectively. Based on the longitudinal conductance of the overburden units, four distinct Aquifer Protective Capacity zones were delineated, namely, poor, weak, moderate and good. Key words aquifer characterization; Basement Complex of Nigeria; groundwater potential; aquifer protective capacity Potentiel en eaux souterraines de la région de socle d'Egbe-Mopa, dans le centre du Nigeria Résumé Cet article présente les résultats d'une enquête sur les potentialités en eau souterraine de la région d'Egbe-Mopa reposant sur le complexe du socle dans le centre du Nigeria. L'enquête a compris une cartographie du sous-sol par l'utilisation de sondes électriques verticales; la mesure de la profondeur de l'eau souterraine, et l'évaluation de la conductivité hydraulique, de la transmissivité et du rendement par l'interprétation d'essais de pompage. Les résultats indiquent que les unités du sous-sol présentent de trois à cinq couches de résistivité, une profondeur de la nappe phréatique de 0-10 m; une épaisseur des terrains stériles de 3-16 m; une conductivité hydraulique de 6,2 10-6 à 3,4 10-4 m/s; une transmissivité de 4,3 10-7 à 2 10-3 m 2 /s, et un rendement de 0,2 à 2,5 L/s. Les évaluations de la charge hydraulique ont révélé un écoulement général des eaux souterraines vers le Nord. L'étude a identifié trois types d'aquifères potentiels de productivité respectivement élevée, moyenne et faible. Sur la base de la conductance longitudinale des unités stériles, quatre zones distinctes de protection des aquifères ont été définies, de qualités respectives médiocre, faible, modérée et bonne. Mots clefs caractérisation des aquifères; complexe du socle du Nigeria; potentiel en eaux souterraines; protection des aquifères

Yu. L. Shchapova International Memorial Conference , LOMONOSOV MOSCOW STATE UNIVERSITY FACULTY OF HISTORY DEPARTMENT OF ARCHAEOLOGY Moscow, Russia, 28–30 May 2020, 2022

Cemetery complex in Cieple from the first half of the 11 th century to the first half of the 12 th century, East Pomerania, Poland, from which the presented beads originate, is a part of settlement complex lays near Vistula River-the main water trade route. Analyzing shapes, colours, decorations of beads in the graves we can observe differences in the wealth of the people they belonged to. Original forms of beads could be a sign of the social status of the owner and the role one played in the community. Their gloss and tinting the glass mass made them an attractive, desirable element of decoration. The type of jewellery, the color and ornament had a symbolic, often apotropaic meaning what is difficult to interpret clearly today. Glass counter from male's grave has such symbolic meaning as well. Beads and other glass items were a comfortable and valued equivalent of money in the Slavic, Scandinavian and Asian territories. The location of the settlement complex in Cieple was convenient in terms of strategic position and communication. Discovered beads and other artefacts are example of imports. They are evidence of commercial and cultural contacts between communities. The multitude of functions that these small, inconspicuous objects performed indicate their value in learning various aspects of life.