African Wildlife & Environment Issue 80

CONSERVATION

Therefore, when basin closure occurs, a different set of policy options need to be considered, simply because the previous solution – dam building and inter-basin transfer – is no longer capable of supplying the water needed for the economic development capable of employing a growing population. Once the water barrier is reached, existing technology becomes irrelevant, so a policy shift is required if national water security is to be retained in a water constrained economy. The important aspect to note is that it is not water for drinking purposes that matters, but rather water as an economic enabler for both job creation and food security. This is the critical policy shift that needs to be considered. South Africa is a perfect example, so work conducted by the CSIR began to define the status of basin closure in the southern African region, with a view to informing evidence-based policy reform with respect to technology needed to alleviate the debilitating impact of a water constrained economy (Turton, 2008;Turton & Ashton, 2008). From this work it became evident that the two largest river basins in South Africa – the Orange (now Gariep) and Limpopo – are both closed. This has major ramifications for national security,

because it implies that there is an absolute upper limit to the economic development that is possible in the face of resource closure. Therefore, it was necessary to take Falkenmark’s Water Crowding Index, which was applicable to a The hydraulic density of population in the major river basins of South Africa indicates that the economic development needed to create full employment of the growing population is unlikely to be possible unless major policy reform embraces technology needed to recover water from waste and desalinate water from the ocean.

national level of analysis, and apply it to specific river basins. The CSIR's results were startling From a comprehensive analysis of all river basins inside the country, it was determined that the Limpopo, Incomati and Maputo basins were manifesting acute symptoms of economic collapse, by virtue of the hydraulic density of population within each basin (Ashton et al ., 2008). In effect the Limpopo is twice the upper value of the globally defined 'water barrier', with the Incomati and Maputo basins crossing that threshold by 2025, and the Gariep approaching that barrier in the same time scale. This has serious implications for the future of the country if left unmanaged.

Work done at the CSIR has mapped out the extent of basin closure in Southern Africa (Turton et al ., 2008).

13 | African Wildlife & Environment | Issue 80 (2021)