South Africa is currently facing a number of significant challenges in regards to water and sanitation. These challenges are complex and have implications for the social, economic, and environmental aspects of the country. The government and other stakeholders are working tirelessly to address these challenges through various initiatives focused on improving infrastructure, ensuring equitable access to clean water and sanitation, and promoting sustainable water resource management.
South Africa’s water availability is a pressing issue. It is ranked as the 40th driest country in the world and classified as water stressed. More than half of its Water Management Areas are experiencing a water deficit, meaning that water withdrawals exceed the sustainable level of supply. This has resulted in many parts of the country already reaching or approaching the point where all accessible freshwater resources have been fully allocated or utilized. The demand for water is predicted to exceed supply as early as 2025, with some studies suggesting that this point was already reached in 2017.
Although surface water is the dominant water source in the country, not all of it can be withdrawn. Some water needs to be reserved in dams and rivers to maintain the ecological health of the water system or meet downstream requirements. The availability of water also varies throughout the year and from one year to the next. The exploitable regular renewable water in South Africa is estimated to be 10.93km3 per annum. Another important source of renewable water is treated municipal wastewater, which is either reused directly or released back into the system for downstream use. Desalination of seawater is also a potential source of renewable water, although it currently constitutes a small portion of the total available water.
To effectively address the water challenges, it is important to acknowledge and accept the country’s water availability realities. This will enable the identification of necessary short-, medium-, and long-term adaptations to decrease the predicted impacts of increased climate variability on various water use sectors and the livelihoods of rural settlements and vulnerable communities.
In terms of rainfall, the availability of freshwater varies across different regions and over time. South Africa’s climate is classified as arid to semi-arid, with an average annual rainfall of approximately 465mm, much lower than the global average of 860mm. The total mean annual runoff is estimated to be 50 x 109m3, which is only 50% of the mean flow of the Zambezi River and 3% of the Congo River. Surface water storage in the country’s largest registered dams plays a crucial role in supporting the growing demands of agriculture and municipal/domestic water use sectors.
Climate change is expected to have various effects on future rainfall patterns in different regions. Increased climate variability will have negative impacts on water availability, quality, and quantity for basic human needs and sanitation. It will also pose threats to water-dependent sectors such as food security, urban and rural settlements, industrial development, energy production, economic growth, ecosystems, and human health. Adaptations and mitigation strategies through water management are critical for sustainable development and achieving global goals related to climate change and disaster risk reduction.
Increased climate variability will further strain South Africa’s already stressed water resources. The projected increase in rainfall variability, as well as the reduction of average rainfall, will place additional pressure on water quantity and quality. The increase in extreme weather events such as floods and droughts will also contribute to water resource challenges. This will have negative effects on agriculture and municipal/domestic water use sectors, which are the primary water users in the country.
Uncertainties still exist regarding the local and catchment-scale effects of climate change on water availability and distribution. However, there is consensus on temperature increases, heavier precipitation, increased heat, and prolonged droughts. Water pollution is also expected to worsen, especially during periods of drought, which poses a significant threat to water security. The expanding population, economic growth, and climate change effects will continue to increase water demand and put pressure on water authorities to ensure reliable and safe water supply for all sectors.
It is crucial to assess the potential impacts of climate change on water demand and implement proactive water resource management strategies. The combination of population growth, economic development, changing consumption patterns, urban expansion, and uncertain water supply will significantly increase water demand. This will have negative social and environmental consequences and may lead to water stress in certain areas.