The changing role of hydrogeology in semi-arid southern and eastern Africa

Robins, Nick; Davies, Jeremy; Farr, J.L.; Calow, Roger

doi:10.1007/s10040-006-0056-x

Cited by 31 publications

(21 citation statements)

References 14 publications

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“…These are significant questions, and we do not go into detail here. However, it is worth emphasising again that data on local hydrological and hydrogeological conditions are often limited or non-existent (Robins et al, 2006;Calow et al, 2009). This makes identifying suitable areas and appropriate technologies difficult.…”

Section: Developing Groundwater For Irrigationmentioning

confidence: 99%

What impact will climate change have on rural groundwater supplies in Africa?

MacDonald

Calow

Macdonald

et al. 2009

Hydrological Sciences Journal

127

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One of the key uncertainties surrounding the impacts of climate change in Africa is the effect on the sustainability of rural water supplies. Many of these water supplies abstract from shallow groundwater (<50 m) and are the sole source of safe drinking water for rural populations. Analysis of existing rainfall and recharge studies suggests that climate change is unlikely to lead to widespread catastrophic failure of improved rural groundwater supplies. These require only 10 mm of recharge annually per year to support a hand pump, which should still be achievable for much of the continent, although up to 90 million people may be affected in marginal groundwater recharge areas (200-500 mm annual rainfall). Lessons learnt from groundwater source behaviour during recent droughts, substantiated by groundwater modelling, indicate that increased demand on dispersed water points, as shallow unimproved sources progressively fail, poses a much greater risk of individual source failure than regional resource depletion. Low yielding sources in poor aquifers are most at risk. Predicted increased rainfall intensity may also increase the risk of contamination of very shallow groundwater. Looking to the future, an increase in major groundwater-based irrigation systems, as food prices rise and surface water becomes more unreliable, may threaten long-term sustainability as competition for groundwater increases. To help prepare for increased climate variability, it is essential to understand the balance between water availability, access to water, and use/demand. In practice, this means increasing access to secure domestic water, understanding and mapping renewable and non-renewable groundwater resources, promoting small-scale irrigation and widening the scope of early warning systems and mapping to include access to water.Key words groundwater; climate; Africa; water supply; drought; agriculture Quel impact aura le changement climatique sur les approvisionnements ruraux en eaux souterraines en Afrique? Résumé Une des incertitudes principales concernant les impacts du changement climatique en Afrique est l'effet sur la durabilité des approvisionnements ruraux en eau. Nombre de ces approvisionnements prélèvent dans des nappes souterraines peu épaisses (<50m) et sont l'unique source sûre d'eau potable pour les populations rurales. Les analyses des études existantes de précipitations et de recharge suggèrent que le changement climatique est peu susceptible de conduire à une défaillance catastrophique généralisée des ressources rurales améliorées en eaux souterraines. Ces dernières ne nécessitent que 10 mm de recharge par an pour satisfaire une pompe manuelle, ce qui devrait être réalisable pour une grande partie du continent, bien que 90 millions de personnes puissent être affectés dans des zones marginales de recharge en eaux souterraines (200-500 mm de pluviosité annuelle). Les leçons apprises sur les comportements des ressources souterraines au cours des sécheresses récentes, renforcées par des modélisations hydrogéologi...

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Section: Developing Groundwater For Irrigationmentioning

confidence: 99%

What impact will climate change have on rural groundwater supplies in Africa?

MacDonald

Calow

Macdonald

et al. 2009

Hydrological Sciences Journal

127

View full text Add to dashboard Cite

show abstract

“…Data are scarce and to a large extent have not been gathered with any rigour over the last two decades. The reasons behind this change are complex (Robins et al, 2006) and include unwanted impacts from decentralisation and rationalisation of government tasks, and the lack of clear demarcation of responsibilities among the various institutions involved in service delivery.…”

Section: A Way Forward For Groundwater Researchmentioning

confidence: 99%

Groundwater research issues in Africa

MacDonald¹,

Adelana²

2008

IAH - Selected Papers on Hydrogeology

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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.

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“…As a result, many supplies are unsuccessful or perform poorly (Robins et al, 2006). Successfully developing groundwater resources sustainably and cost-effectively on the scale required to help achieve the Millennium Development Goals is not trivial.…”

Section: Introductionmentioning

confidence: 99%

African hydrogeology and rural water supply

MacDonald¹,

Davies²,

Calow³

2008

IAH - Selected Papers on Hydrogeology

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The widespread development of groundwater is the only affordable and sustainable way of improving access to clean water and meeting the Millennium Development Goals for water supply by 2015. Current approaches to rural water supply, in particular demand driven approaches and decentralisation of service delivery have many benefits to the overall efficacy and sustainability of water supplies, however, problems arise when projects do not take into

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The changing role of hydrogeology in semi-arid southern and eastern Africa

Cited by 31 publications

References 14 publications

What impact will climate change have on rural groundwater supplies in Africa?

What impact will climate change have on rural groundwater supplies in Africa?

Groundwater research issues in Africa

African hydrogeology and rural water supply

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