Water realities for 2020
WHEN she addressed the Water Institute of Southern Africa’s (Wisa) conference in South Africa, Sunita Narain of the Centre for Science and the Environment, India, observed that change in weather patterns on the back of major climatic changes could be evidenced through both droughts and floods occurring simultaneously in the same country.
This is a phenomenon we are living through with the serious flood damage in some parts of the country while others are in the grip of extreme water scarcity.
This physical phenomenon of extreme weather which is rapidly defining our new normal is greatly exacerbated by the metaphoric drought of ideas and imagination compounded by the floods of prejudice and negativity.
This is particularly pronounced in the commentary of some regular water and development experts that fill our media spaces – a clan of Afro-pessimists in general and naysayers.
One of the questions raised in response to the launch of the water master plan by Minister Lindiwe Sisulu was “where would the water come from?”
South Africa has the accolade of being in the world’s top 10% of water-knowledge producers on the back of a highly-productive research community of practice, so let us assist in hydrating this drought of ideas.
Accepting that the public is aware of the plans for various surface water augmentation schemes of dams and pipelines in process at the Department of Water, let us concentrate on the other, even more, attractive options.
First, we have the potential of sustainable groundwater harvesting from renewable aquifers of between 8 to 12 billion m3 (an m3 is 1 000 litres) annually. Our current use is only between 2 and 4 billion m3, depending on the season.
Core to the sustainability of this resource is frequent and regular replenishment. Groundwater also trumps surface water storage as it is largely immune from evaporation.
A great example is the Atlantis aquifer outside Cape Town, which is being replenished with a combination of stormwater and treated wastewater. Its current potential for supply is between 15 and 20 million litres a day.
A further unexploited resource is seawater along the coast and brackish and polluted waters inland. The traditional barrier to entry of energy demand has been largely solved by technological advancement and renewable energy options, and costs will depend on economies of scale, on the one hand, and the planning model on the other.
Desalination investments could easily decrease the current strain on surface water systems by at least 10%. For this to work, it is essential that desalination plants are retained as a permanent part of the water mix.
The possibilities were shown in the Ndlambe district municipality in the town of Albany in the Eastern Cape where Minister Sisulu launched of the next phase of its desalination, now utilising a sand water harvesting system to supplement the seawater feed. The town is now predominantly supplied with these sources supplemented by rainwater harvesting tanks. It is, if you like, off the surface water grid.
Let us reflect this year on the South Africa we really want, and whether our current actions help us to get to the right space or is it taking us the other way.
Naidoo is chief executive of the Water Research Commission.