The big picture

• Use of water has grown at twice the rate of population growth over the last century
• About 1.2-billion people live in regions of water scarcity; another 500-million will soon be in this situation
• 1.25-million additional people in South Africa received access to basic water service in 2006-7
• 75% of South Africa’s population is now provided with free basic water
• Demand for water will exceed supply by 2025 at current usage rates though climate change could bring this forward to 2015

South Africa is the thirty-third driest country in the world with water resources that, though variable across the country, are scarce and extremely limited. The combined flow of all the rivers in the country, according to the 2004 National Water Resource Strategy (NWRS), amounts to about 49 000 million cubic metres annually, less than half of that of the Zambezi River.

Four of the country’s main rivers – the Limpopo, Inkomati, Pongola and Orange – together drain about 60% of the country’s and contribute around 40% of its total surface runoff. Water from these rivers supports 70% of South Africa’s GDP and around 70% of its population.

Surface water resources provide most of the country’s urban, industrial and irrigation requirements and are highly developed across the country. South Africa has over 500 dams, more than 300 of them major bodies of water with a full supply capacity of more than one million cubic metres and a total capacity of more than 32 400-million cubic metres.

Together with Zimbabwe’s 200-plus dams, these account for more than 60% of the total number of dams on the continent. As a whole the continent accounts for approximately 9% of the world’s total freshwater resources. Over the last decade or so, Africa experienced close to one-third of all global water-related disasters. These events, in the main, droughts, have affected more than 120-million people. Looking ahead, the picture does not get much more promising: at least 25 African countries, South Africa among them, are expected to experience water scarcity or stress over the next two to three decades.

Climate change
Some climate models suggest that rises in global temperatures could increase the variability of climate and decrease rainfall in South Africa. They show that stream flow could decrease by as much 10% by 2015, especially in the most affected parts of the Western Cape, and suggest that the reduction in runoff will progress to the east coast by 2060. An increase in the variability of stream flow would mean that natural yields and reliability would be reduced and the unit cost of water from dams would increase even if average rainfall were to remain the same.

Recent opinions and responses
Given these considerations it is perhaps not surprising that the Sunday Times recently published an article suggesting that South Africa was facing a water crisis equivalent to the electricity crisis that the country is currently undergoing – both are, after all, major issues affecting, or with the potential of affecting, both population and economy in adverse ways.

The Department of Water Affairs and Forestry and its minister Lindiwe Hendricks were quick to respond to the newspaper’s allegations. Hendricks pointed out that the newspaper article did not cover the measures and responses taken by the department to deal with issues of water management. It was indicated that, among other things, that the department was running a pilot programme on water conservation in cooperation with eight municipalities that was expected to result in water savings of at least 15% in the municipalities concerned; and that a budget of R1.25-billion over a period of five years had been set aside to address infrastructure maintenance needs of dams. Forty-two projects are currently between the planning and construction phases, according to the department.

However, a few days after these announcements, the World Wildlife Fund of South Africa chief director Morne du Plessis told the media that the electricity crisis could put additional pressure on water resources. With 98.4% of the country’s consumable water accounted for, Du Plessis said that extra pressure on Eskom to produce power, water wastage in the country and the adverse effects of climate change meant that there was little room in which to manoeuvre and South Africa could be out of water by 2025.

Future perspectives on water management in South Africa
Most economic and population growth in the country will happen in the major urban areas, making water demand management there highly important. Of relevance here are the following water management areas (WMAs) according to the (NWRS):

• Crocodile West and Marico: The Pretoria-Johannesburg area in the upper reaches of the Crocodile catchment will in future require large additional transfers of water, resulting in growing quantities of return flows becoming available downstream of these centres.
• Olifants: Current deficits and provision of water supplies to future power generation and mining in the area and in the Limpopo WMA will need ot be addressed.
• Inkomati: Current deficits and impacts associated with the implementation of reserve water supply will need to be addressed.
• Upper Vaal: This WMA, the main source of water for Gauteng, should be adequately supplied until close to 2025, however future growth in Johannesburg may require transfer of water into the area.
• Mvoti to Umzimkulu: The Durban-Pietermaritzburg area must be ensured of adequate supplies of water.
• Berg: As with the Upper Vaal for Gauteng, should high rates of economic growth or the adverse effects of climate change be experienced (as some scenarios suggest), the area could undergo water stress.

The practicalities of now
Engineering News reported in December in one of its ‘Projects of the year’ features that the construction of the Berg River dam was nearly complete, with construction activities slated for completion in March. The Berg Water Project (BWP) will supplement the Western Cape’s water supply until 2014. The Department of Water Affairs and Forestry has also begun a reconciliation study for the province in order to provide a decision-support framework to enable timeous decisions on water resource interventions, allowing the Western Cape to meet water requirements until 2030.

The key objectives of the project were to store water during the last winter and to deliver water to Cape Town in December last year. Overall, the aim of the BWP is to overcome Cape Town’s impending water shortage.

It will become part of the province’s water supply system (WSS) and additional water from the project will be used in the Cape Town area for domestic and industrial use. The WSS consists of the Theewaterskloof, Voelvlei, Wemmershoek, Steenbras Upper, Steenbras Lower, Kogelberg and Palmiet dams.
 
On the whole, tight and accurate planning is going to continue to be required to ensure that South Africa’s water resources are augmented until the mid-2020s and beyond.