Latest News Archive

Please select Category, Year, and then Month to display items

High risk that water demand in Gauteng will exceed available resources

08 April 2025 | Story Andre Damons | Photo Andre Damons

DrSophie-Biskop_ProfFrancois-Engelbrecht — Dr Sophie Biskop from the Department of Geography at the Schiller University Jena, Germany, and Prof Francois Engelbrecht, a Professor of Climatology at the Global Change Institute (GCI), University of the Witwatersrand, at the Southern African Mountain Conference (SAMC).

The severe El Niño drought of 2015/16, which culminated in the Vaal dam reaching an alarming low water level (~25%), prompted scientists to try and predict whether climate change could bring a drought so severe and long lasting that Gauteng could run out of water.

Prof Francois Engelbrecht, a Professor of Climatology at the Global Change Institute (GCI), University of the Witwatersrand, is one of the scientists working on this project and says though they cannot predict a Day Zero drought with certainty, he thinks it is possible that Gauteng might run out of water in the 2030s or 2040s.

“This is the biggest climate change risk South Africa faces”, he said.

Prof Engelbrecht and Dr Sophie Biskop from the Institute of Geography at the Friedrich Schiller University Jena, Germany, together with other scientists are working on a project involving hydrological modelling to predict and prevent a Day Zero from happening. Dr Biskop presented their research paper titled ‘Projected hydrological futures of South Africa's mega-dam region’ at the second Southern African Mountain Conference (SAMC2025) in March, indicating there is a high risk that the water demand in Gauteng will exceed available water resources within the Integrated Vaal River System (IVRS) under future climate change.

Gauteng may be severely compromised

The IVRS, a large, complex water system comprising water resources of different river basins, and several mega-dams within, has been constructed to secure the water supply of the Gauteng province, the economic hub in South Africa.

According to the researchers, Southern Africa is a water-stress hot spot and is projected to become significantly warmer and likely also drier under global climate change, increasing the risk of devastating hydrological droughts. The IVRS, Dr Biskop told the attendees, is vulnerable to the occurrence of multi-year droughts as experienced between 2012 and in 2016. The alarming low water level of the Vaal dam after a period of drought of 2015/16 provided early warning that water security of Gauteng may be directly and severely compromised in a changing climate. Potential evapotranspiration will increase as a consequence of strong regional warming.

Answering questions

“There is consequently a high risk that the water demand in the Gauteng province will exceed available water resources within the IVRS under future climate change. This raises the question if under ongoing climate change the natural hydrological system (without considering water transfers between dam catchments) can maintain dam levels in South Africa’s eastern mega-dam region, and particularly within the Lesotho Highlands,” explained Dr Biskop.

“To answer this question, the aim of our study is to quantify future water balance changes of several dams under changing climate conditions using the Jena Adaptable Modelling System (JAMS), a software framework for component-based development of environmental models. For this purpose, we build process-based hydrological models for several dam catchments.”

She said an ensemble of high-resolution regional climate change projections is subsequently used as forcing, to generate future hydrological projections. The analysis of projected changes in hydrological system components (precipitation, evapotranspiration, run-off) provides probabilistic estimates of the occurrence of a regional climate change tipping point - when the natural water supply can no longer achieve the full storage capacity of the mega-dams which supply the Gauteng region.

Working to prevent Day Zero

According to Prof Engelbrecht, they are working with the City of Johannesburg, the National Department of Water and Sanitation and Rand Water on this project. Their hope for this research is to create awareness in order to try and prevent Day Zero from happening. They also hope to assist these role players in building resilience and help them prepare for Day Zero. Their work with the City of Johannesburg also includes helping the city to reduce water wastage and change water users’ behaviour as well as formulating a disaster management plan should Day Zero happen.

The Southern African Mountain Conference (SAMC) series is unique as it seeks to integrate science, policy and practitioner sectors for sustainable interventions in southern African mountains. SAMC events are conceptualised by the Afromontane Research Unit (ARU) of the University of the Free State (UFS), the African Mountain Research Foundation (AMRF) and Global Mountain Safeguard Research (GLOMOS), a joint initiative between Eurac Research and the UNU Institute for Environment and Human Security. These three organisations form the Primary Partners, with the SAMC series being implemented by The Peaks Foundation (a non-profit company). SAMC2025 is being held under the patronage of UNESCO.

News Archive

Carbon dioxide makes for more aromatic decaffeinated coffee

2017-10-27

The Inorganic Group in the Department of Chemistry
at the UFS is systematically researching the utilisation
of carbon dioxide. From the left, are, Dr Ebrahiem Botha,
Postdoctoral Fellow; Mahlomolo Khasemene, MSc student;
Prof André Roodt; Dr Marietjie Schutte-Smith, Senior Lecturer;
and Mokete Motente, MSc student.
Photo: Charl Devenish

Several industries in South Africa are currently producing hundreds of thousands of tons of carbon dioxide a year, which are released directly into the air. A typical family sedan doing around 10 000 km per year, is annually releasing more than one ton of carbon dioxide into the atmosphere.

The Inorganic Chemistry Research Group in the Department of Chemistry at the University of the Free State (UFS), in collaboration with the University of Zurich in Switzerland, has focused in recent years on using carbon dioxide – which is regarded as a harmful and global warming gas – in a meaningful way.

According to Prof André Roodt, Head of Inorganic Chemistry at the UFS, the Department of Chemistry has for the past five decades been researching natural products that could be extracted from plants. These products are manufactured by plants through photosynthesis, in other words the utilisation of sunlight and carbon dioxide, nitrogen, and other nutrients from the soil.

Caffeine and chlorophyll
“The Inorganic group is systematically researching the utilisation of carbon dioxide. Carbon dioxide is absorbed by plants through chlorophyll and used to make interesting and valuable compounds and sugars, which in turn could be used for the production of important new medicines,” says Prof Roodt.

Caffeine, a major energy enhancer, is also manufactured through photosynthesis in plants. It is commonly found in tea and coffee, but also (artificially added) in energy drinks. Because caffeine is a stimulant of the central nervous system and reduces fatigue and drowsiness, some people prefer decaffeinated coffee when enjoying this hot drink late at night.

Removing caffeine from coffee could be expensive and time-consuming, but also environmentally unfriendly, because it involves the use of harmful and flammable liquids. Some of the Inorganic Group’s research focus areas include the use of carbon dioxide for the extraction of compounds, such as caffeine from plants.

“Therefore, the research could lead to the availability of more decaffeinated coffee products. Although decaffeinated coffee is currently aromatic, we want to investigate further to ensure better quality flavours,” says Prof Roodt.

Another research aspect the team is focusing on is the use of carbon dioxide to extract chlorophyll from plants which have medicinal properties themselves. Chemical suppliers sell chlorophyll at R3 000 a gram. “In the process of investigating chlorophyll, our group discovered simpler techniques to comfortably extract larger quantities from green vegetables and other plants,” says Prof Roodt.

Medicines
In addition, the Inorganic Research Group is also looking to use carbon dioxide as a building block for more valuable compounds. Some of these compounds will be used in the Inorganic Group’s research focus on radiopharmaceutical products for the identification and possibly even the treatment of diseases such as certain cancers, tuberculosis, and malaria.

Back

Economic and Management Sciences

Education

Health Sciences

The Humanities

Law

Natural and Agricultural Sciences

Theology and Religion

Open Distance Learning

Business School

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept