Focus: Groundwater Resue

Although my previous blogposts have been gloomy, my next two (optimistically) explore potential solutions to transboundary water challenges. This week focuses on solutions that increase supply of water and next week looks at reducing demand. 

Transboundary waters also consist of those underground: TBAs. Altchenko and Villholth (2013: 1497) mapped “80 shared groundwater aquifers-systems superimposed on 63 transboundary rivers”, constituting a huge “42% of African territory”. Although Southern Africa has the most TBAS at 35, only 12% of South Africa’s territory is within TBAs (Table 1). The already high evapotranspiration rates of South Africa’s pivotal basins will escalate with climate change, thus implying the significant role of TBAs in increasing water supply and securing long-term development (Villholth 2013). This, accompanied by large uncertainties around TBAs, highlights the need for better understanding and cross-boundary monitoring (Goulden et al. 2009).

Table 1: Approximate percentage of states located within TBAs. 

Source: Altchenko and Villholth (2013).

The 1989 Bellagio Draft Treaty is probably the first ‘soft law’ – lacks enforcement, see blogpost 2 – that recognised TBAs and sought to identify a transboundary approach for its equitable use and protection (Hayton and Utton 1989). Since then, the UN (2009) released the Draft Articles on Law of TBAs which SADC is preparing to adopt as well as employ integrated water-resource management to identify ‘troublesome’ TBAs (Altchenko and Villholth 2013). Eckstein and Eckstein (2005) also developed six types of TBAs to aid management (see Figure 6). But I would agree with Scheumann and Alker (2009) that these are very simplified TBAs (e.g. more than two riparians). Still, TBAs “hold promise for democratic development and climate-proof solutions due to their dispersed availability and large protected storages” (Altchenko and Villholth 2013: 1506), and thereby could increase water supplies of water-stressed South Africa and maintain its hydro-hegemonic development.

Figure 6: Eckstein and Eckstein’s (2005) six types (copy). 

Source: Scheumann and Alker (2009).

Relooking at troublesome TBAs, one is Pomfret-Vergelegen dolomite aquifer (PVDA) between Botswana and South Africa (AFS7 in Figure 7). Giordano (2006) denotes that South Africa is the biggest continental groundwater user and borehole constructor. Dam building upstream (reduces stream-flow, high evaporation) has also impeded PVDA’s recharge (Turton et al. 2007). Therefore South Africa’s monopoly of PVDA has, geology permitting, hostile impacts on the transboundary ecosystem and its riparians: a true tragedy of the commons. TBAs can entrench pre-existing power-relations if devised within South Africa’s securitisation frameworks (Altchenko and Villholth 2013). Furthermore, extensive exploitation and land-use changes for development would exacerbate recharge rates, especially of non-renewable fossil water (Goulden et al. 2009). Consequently, “interstate cooperation and management over TBAs is imperative, as utilisation grows, so one state’s solution does not become another’s problem” (Scheumann and Alker 2009: 793). Perhaps the answer for South Africa is reducing demand, not increasing supply...

Figure 7: Map of African TBAs and transboundary basins.

Source: Altchenko and Villholth (2013).

References

Altchenko, Y. and K. Villholth (2013) “Transboundary Aquifer Mapping and Management in Africa: A Harmonised Approach”, Hydrogeology Journal, 21, 1497-1517.

Eckstein, Y. and G.E. Eckstein (2005) “Transboundary aquifers: conceptual models for development of international law”, Ground Water, 43, 5, 679–690.

Giordano, M. (2006) “Agricultural Groundwater Use and Rural Livelihoods in Sub-Saharan Africa: A First-Cut Assessment”, Hydrogeology Journal, 14, 310-318.

Goulden, M., D. Conway and A. Perschino (2009) “Adaptation to Climate Change in International Rivers Basins in Africa”, Hydrological Sciences Journal, 54, 5, 805-828.

Hayton, R.E. and A.E. Utton (1989) “Transboundary Groundwaters: The Bellagio Draft Treaty”, Natural Resources Forum, 29, 663-722.

Scheumann, W. and M. Alker (2009) “Cooperation on Africa's transboundary aquifers - conceptual idea”, Hydrological Sciences Journal, 54, 4, 793-802.

Turton, A.R., L. Godfrey, F. Julien and H. Harringh (2007) “Unpacking Groundwater Governance through the Lens of a Trialogue: A Southern African Case Study”, in S. Ragone, N. Hernnández-Mora,, A. de la Hera, J. McKay and G. Bergkamp (eds) The Global Importance of Groundwater in the 21st Century: Proceedings of the International Symposium on Groundwater Sustainability, Ohio: National Groundwater Association Press,  359-70.

Villholth, K. (2013) “Groundwater Irrigation for Smallholders in Sub-Saharan Africa – A Synthesis of Current Knowledge to Guide Sustainable Outcomes”, Water International, 38, 4, 369-391.