SA is classified as water-scarce country often ranked among world's 30 driest with average rainfall about 500mm.
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South Africa is classified as a water-scarce country, often ranked among the world’s 30 driest. Our average annual rainfall is about 500mm, well below the global average of roughly 860mm.
Water availability varies by region, with the greatest stress in high-population areas such as Gauteng, eThekwini and Cape Town. Many people experience a water crisis, but how much of this is really a crisis of management and innovation?
About 32% of our potable water is physically wasted through leaking pipes and reservoirs, ranging from 19% in the Western Cape to 44% in the Northern Cape.
Plugging leaks to Western Cape levels or lower would free up an enormous volume of water. This requires investment to replace old pipes, but sophisticated leak detection and pressure management can deliver gains at lower cost.
More than 60% of our wastewater treatment plants are critical or poor – fixing them would stop their pollution of rivers and dams and expand usable water supply.
If we upgraded our wastewater treatment as Israel has done, more than 80% of treated wastewater could be reused for agriculture. Israel also pioneered largescale seawater desalination, which now provides 80 to 85% of its urban drinking water.
In Namibia, Windhoek has safely recycled its sewage into drinking water since 1968, supplying 20% to 30% of the city’s needs.
Acid mine drainage from disused mines is a huge pollution problem in Gauteng, but can provide a substantial boost to water supply if properly treated.
High technology may not be needed as Cape Town uses manual labour to free up water by clearing invasive alien plants.
Clearing of over 50 000 hectares has restored about 18 billion litres a year and a full clearing would release 55 billion litres.
Rainwater harvesting can be expanded, as can storage dams that capture flood run-off that is lost to the sea.
The other side of the equation is to use water more efficiently. Drip irrigation can save between 30% to 60%, compared to flood or overhead sprinkler systems.
We cannot control how much rain falls, but we can control how much water we waste, how much we recycle and how intelligently we use what we have.
The greatest obstacle to solving our water crisis is not a lack of water, but a lack of imagination, innovation and leadership.
