The southern part of the Kalahari lies in the Lower Orange River Basin and the so-called
‘Stampriet Artesian Basin’ in Namibia is part of a shared aquifer group that straddles the bor-der between Botswana, Namibia and South Africa (aquifer No. 13 in Figure 1). The quality of the water in the aquifers decreases in theflow direction towards south-western Botswana and the north-western Cape in South Africa. Water is often brackish to saline in this area, known in Namibia as the salt block, and
this was probably due to leakage and evapora-tion through time.
This system was investigated in detail by Pacific Consultants International and the Namibian Department of Water Affairs and Forestry. The project was largely funded by the Japanese Government through the Japanese International Cooperation Agency (JICA). There are two confined regional artesian aquifers in the Karoo sediments, overlain by the Kalahari sediments that often contain an unconfined aquifer system. The study confirmed that extensive faulting resulted in a complex nature of this aquifer system. Recharge into the sys-tem in the north-western part of the basin is from structures such as faults, linked to sink-holes that serve as the main conduits for recharging the artesian sandstones. The recharge mechanism in the Botswana / Namibia boundary area is still unknown.
Recommendations were made to improve the management of the aquifers in terms of sustainable utilization, and on the rehabilitation of inadequately designed boreholes that inter-sect the artesian aquifers and cause losses due to leakage from the artesian aquifers into the upper Kalahari sediments. Further work, to better understand and quantify the degree of losses due to leakage from the artesian aquifers, has been proposed.
In Namibia this aquifer system is the main source of water supply for agricultural devel-opment as well as for the five urban centres within the region. In Botswana this area is sparsely populated although water is required for stock watering, game, and smaller villages that are in need of increased water supply, and further development is envisaged. Further-more, mining companies are involved in explo-ration activities within the area. Within South Africa the water needs from this system is mainly required in a large game reserve and for stock watering on the commercial farms. The system needs to be jointly studied by Botswana, Namibia and South Africa. It is also envisaged that this study can be used as a model for similar studies in the rest of the SADC.
With the assistance of UNESCO a four-day fol-low-up meeting was held in Namibia within the
project area during April 2008, and was attended by the three basin states and other stakeholders. The purpose was to consolidate the knowledge of the Stampriet Kalahari/Karoo Basin in the three countries sharing the aquifer;
to identify knowledge gaps; to define a common investigation program; and propose measures to commonly manage the aquifer. A Technical Task Team was formed to represent the three countries at the relevant ORASECOM meetings and to serve as a mechanism to drive the project. It was decided at the meeting to demarcate and jointly look at two areas within the Basin, one in the south neighbouring Namibia and South Africa, and another area to the north neighbouring Namibia and Botswana.
The delegates of all three countries were much in favour of cooperating in this project. A study proposal is being formulated that addresses the knowledge gaps and the investigation needs as experienced by the three participating coun-tries. Apart from data exchange the project will probably concentrate on recharge assessment;
water quality issues; harmonising legal and technical regulations regarding drilling and water use; and establishment of a common monitoring network. Investigations into natural leakage and identification and repair of leaking boreholes are the more challenging issues that need to be addressed.
This joint project will establish the information necessary for Transboundary groundwater security that could lead to amongst other benefits, to promote the development of a Transboundary Game Park between the three countries. An exchange of groundwater data and information will furthermore promote bet-ter long-bet-term management to the benefit of all three countries.
The way forward
The initiative with the Stampriet Kalahari / Karoo Basin TBA should serve as a pilot approach for other TBA areas considered within the SADC.
Climatic variability amplifies the need for sound management of TBAs, especially in the
aforementioned location which is predicted to receive reduced rainfall because of climate change.
In the way forward international financial insti-tutions should be made aware of the important role of groundwater to facilitate sustainable regional development of Southern Africa. Joint studies on transboundary aquifers within the work of the existing river basin institutions must be encouraged and this will lead to bet-ter integrated wabet-ter resources management. It is clear that external international support for these activities will enhance the outcome to the benefit of the local population, socio-economic development and conflict resolution
The concept of an International Groundwater Resources Assessment Centre (IGRAC), an initiative of UNESCO and WMO, launched in February 1999, has resulted in a WEB-based database system for transboundary aquifers, including those in Southern Africa, to provide in short time, easily manageable storage facili-ties for existing information from groundwater studies and for future transboundary aquifer studies. The interactive meta-information database on organizations, people and docu-ments containing data supplied by individual countries, as well as a digital project workspace set up and facilitated by IGRAC will allow for improved communication between all partici-pating SADC countries.
Conclusions
Groundwater already does, and will increas-ingly have to play a crucial role in the fulfil-ment of the African Water Vision towards poverty alleviation, socio-economic develop-ment, regional cooperation and environmental protection. In contrast to its strategic role, groundwater has remained a relatively poorly understood and managed resource. This has become a clear threat to sustainable water service delivery and meeting the Millennium Development Goals on water.
In terms of existing international and regional
water law in the SADC, all parties sharing trans-boundary surface water or groundwater resources have an obligation to ensure close cooperation with the objective to achieve the judicious, sustainable and coordinated mana-gement, utilization and protection of the resource.
Southern Africa is a region where many sover-eign states have committed themselves to par-ticipate constructively in activities related to the management of shared watercourse systems.
The best way to initiate the joint studies on TBAs is to integrate this issue within the work of the existing river basin institutions that have been established by the respective Basin States to advise the Governments on the inves ti-gation, development, utilisation and mana-gement of shared water resources. This will also lead to a better integrated water resources management approach for the River Basin Organisations when addressing current groundwater utilisation issues in the SADC.
This information, based on the evaluation of groundwater-related data, should be exchanged and combined in a joint mana-gement strategy.
The management of transboundary aquifers is subject to bilateral and multilateral agreements on water abstraction, prevention of pollution and any other relevant issues. A proper hydro-geological characterization of a specific aquifer system combined with an understanding of the legal, socioeconomic, institutional and envi-ronmental issues of the countries sharing the groundwater resource is crucial in this context.
Substantial political, socio-economic, technical and ecological benefits can be obtained by all parties participating in the joint management of transboundary aquifers.
It is therefore of paramount importance that the required labour force and funding is pro-vided by the respective countries to study the Stampriet Kalahari / Karoo Basin TBA. Such a commitment will certainly enhance the oppor-tunity to solicit international donor support that can complement local technical expertise and assist in securing management strategies that will enhance joint cooperation for the benefit of the people within the three Basin States. The wider purpose of the study is to
propose possible ways of implementing better transboundary aquifer management within the rest of the SADC.
A challenge for Africa concerning Transbound-ary Groundwater is to overcome and manage the conflict of interests due to its unseen and poorly understood nature, and to prevent the unwillingness to cooperation on resource shar-ing. These problems are exacerbated through the well-known human challenges of equity, justice, power and governance regarding any finite natural resource and particularly pressing for groundwater because of its hidden nature.
Appropriate governance structures in place to help achieve the objectives of equity and sustainability of Transboundary groundwater will promote joint cooperation between the countries.
References
Heyns P., 2006. Exposing Transboundary Aquifers: A Resource for Cooperation in
Southern Africa, Stockholm World Water Week, Sweden.
Christelis G., Heyns P., Kirchner J., Makarigakis A., and Margane A., 2007. Transboundary Groundwater Management in the River Basin Organisations of SADC with Special Reference to the Namibian case, Stockholm World Water Week, Sweden.
UNESCO, 2004. ISARM Africa - Managing Shared Aquifer Resources in Africa, Pro-ceedings of the 2002 Int. Workshop, Tripoli, Libya.Appelgren B. (editor). IHP-VI, Series on Groundwater No. 8. UNESCO, Paris.
Molapo P. and Puyoo S., 2004. Transboundary Aquifer Management in the Context of Inte-grated Water Resources Management in the Southern African Development Community (SADC region). In: ISARM Africa - Managing Shared Aquifer Resources in Africa, Pro-ceedings of the 2002 Int. Workshop, Tripoli, Libya.Appelgren B. (editor). IHP-VI, Series on Groundwater No. 8, pp. 31-38. UNESCO, Paris.
Vasak C., 2005. Groundwater Resources and Transboundary Aquifers of Southern Africa (Second Draft). International Groundwater Resources Assessment Centre (IGRAC), Netherlands.
L’année 2007 a été très riche au niveau de la prise de conscience sur le changement clima-tique. La publication du 4erapport d’évaluation du Groupe Intergouvernemental d’Experts sur l’Evolution du Climat (GIEC), couronnée par le prix Nobel de la Paix, a permis de fournir à la communauté scientifique et aux décideurs un état des connaissances très large sur le change-ment climatique, et ses impacts. Cependant, de nombreux efforts restent à fournir pour amé -liorer notre compréhension de ces phéno -mènes complexes, en particulier en Afrique, ainsi qu’au niveau des eaux souterraines. En effet, il existe dans ce champs d’étude un point commun notable entre l’Afrique et les eaux souterraines: l’Afrique est le continent dont on connaît le moins le climat actuel et ses futures évolutions, et les eaux souterraines sont la
composante du cycle hydrologique dont on connaît le moins les relations avec les change-ments climatiques (IPCC, 2007).