CIT Y OF TSHWANE
Fanus Fourie, national chairperson, Ground Water Division
How much groundwater is used in South Africa? FF Between 13% and 16% of the nation's total water supply originates from groundwater. However, this would exclude all boreholes that are not registered at the Department of Water and Sanitation.
Is groundwater an underutilised resource? Yes and no. Yes, because 7.5 billion m3 per annum of groundwater is available and there is 10 billion m3 per annum of surface water, but almost all of the surface water is fully allocated. Around 19% of all groundwater is found in KwaZuluNatal, but most of the province’s water is sourced from a river or a dam. Groundwater is definitely underutilised in KwaZulu-Natal. South Africa is currently using around 50% of available groundwater and can still develop the other 50%. But if a community has a river, it will not go to the expense of drilling a borehole and utilise available groundwater. There is around 2 billion m3 per annum of groundwater that can be developed. On the other hand, it is not underutilised. In fact, groundwater is overutilised in places like the Karoo. Groundwater has massive potential. Cape Town will be pumping roughly 10 Mℓ of groundwater a day. Once Port Elizabeth’s groundwater scheme
Groundwater: hidden but never forgotten
is in place, roughly 15% to 20% of all of its water will come from groundwater. Groundwater in Brandvlei in the Karoo is pumped as far as 50 km from the town. Many towns and communities are supplied solely from groundwater. In certain cases, we can utilise more groundwater; in other cases, we need to focus on protecting our groundwater. Groundwater protection zoning is aimed at safeguarding the quantity and quality of groundwater. A community cannot live on top of a wellfield. Petrol stations or ventilated improved pit latrines should not be close to a borehole. In some cases, development needs to be reconsidered if groundwater earmarked by the municipality for community use will be impacted if this construction goes ahead.
How can we better manage groundwater? Groundwater management seeks to balance and mitigate the detrimental impacts of the development and operation of groundwater. There are a number of elements to consider: • Protect the wellfield: If people are living on top of your aquifer, there is a high likelihood that it may be polluted. The wellfield needs to be fenced off. But for maintenance and daily operations, there must be easy access to the borehole. • Planning: There may be a possibility that one requires more water from the borehole than can be extracted. It may
Par t of the Geological Society of South Africa (GSSA), the Ground Water Division (GWD) is a body of scientists and technicians who have an interest in the optimal development of South Africa’s groundwater as a limited natural resource. IMIESA inter viewed its national chairperson Fanus Fourie.
GROUND WATER DIVISION (GWD) • Established in 1978 • Essentially a non-profit association, it is committed to upholding and promoting professionalism in the field of groundwater among its membership • The GWD is a community of professionals who help South Africans understand and manage groundwater • The 17th biennial Groundwater Conference will be held between 17 and 20 October as a hybrid event, broadcasting from Gauteng • The GWD focuses on networking, knowledge transfer, as well as capacity and awareness building through initiatives such as conferences, seminars and courses, talks and media relations, publications and sponsorships • It has a large database of registered professional hydrogeologists • For more information, visit the GWD website https://gwd.org.za
take two to four years to get another groundwater scheme up and running. • Maintenance: Often, when a borehole is not working, it is because a pipe broke, or there is a power issue, or a stolen cable or faulty pump or tap. • Daily operations: Water levels need to be measured on a daily basis. If no one knows how much water has been
extracted, and how much the aquifer has been replenished, the borehole may dry out. • Groundwater education: The community using the borehole water needs to understand where the water is coming from, how much water can be used, and how to avoid polluting the aquifer. The GWD is available to provide help and technical advice.
IMIESA June 2021
43
