GLOBAL HYDROGEOLOGY CONGRESS
Groundwater — the hidden treasure beneath our feet is key to water security
In the face of rising urbanisation, climate change, weather variability and resource degradation, hydrogeologists from around the world gathered in Cape Town this week to chart a way forward on water security, using a hidden treasure underneath our feet — groundwater.
The Worldwide Congress of the International Association of Hydrogeologists (IAH) takes place this week in Cape Town, which is no stranger to the challenges associated with water resources and the importance of groundwater after its 2017 Day Zero scare when the city came close to running out of municipal water supply.
The City of Cape Town Mayco member for water and sanitation, Zahid Badroodien, said: “In our city, we have witnessed the power of groundwater as a key resource in times of need. During the water crisis, it was the sustainable management of our groundwater reserves that played a pivotal role in averting a catastrophe.”
Groundwater served as a crucial reserve of freshwater that sustained communities, agriculture and industries and staved off Day Zero.
“With a growing population and the increasing unpredictability of climate change, the need for a resilient and sustainable water supply has never been more pressing. Groundwater, as an underground reservoir, provides a buffer against the uncertainties of surface water availability,” Badroodien said.
Groundwater makes up the bulk of the world’s freshwater resources and is a key to water security and resilience. Groundwater constitutes 13% of South Africa’s water supply.
Dr Shafick Adams, a hydrogeologist at the Water Research Commission, said this 13% provides water to 56% of the population, either as a sole source or combined with surface water. That is just over 34 million people within 23,746 settlements (78.5% of all settlements in the country).
Adams said that expanding groundwater use could help communities and the state build resilience to the impacts of climate change and other drivers of water demand, such as urbanisation, population growth, industrialisation, and agricultural expansion.
Read more in Daily Maverick: Groundwater management skills are flowing out of SA and metros are doing nothing to stop the loss
Understanding, managing and expanding groundwater usage is the task handed down to the 500 groundwater experts from 52 countries at the 50th IAH Worldwide Congress this week, organised by the South African National Chapter of the International Association of Hydrogeologists, and the Groundwater Division of the Geological Society of South Africa.
Julian Conrad, the co-chair of IAH2023 and managing director at Groundwater and Earth Sciences South Africa, said the theme, “‘Groundwater: A matter of scale’, provides an opportunity to ensure this precious and almost wholly hidden resource is understood in more detail and from various angles to ensure its usability for generations to come and for it to continue playing its critical role within the water cycle and ecosystems’ functioning.”
A water-sensitive city
After field excursions on Monday to view the Cape Flats urban aquifer development, Conrad said groundwater would actively facilitate Cape Town’s transition to a water-sensitive city.
Tebogo Madlala, a hydrogeologist at the CSIR Water Research Centre, said some of the issues in the groundwater sphere that needed to be properly managed to afford citizens the right to sufficient water, were the lack of infrastructure maintenance, with boreholes caving in, and inefficient monitoring of water levels and water quality.
Madlala said, “You’ll find an event where groundwater is overpumped by certain people or you find issues of saline water intrusion, and those could emanate either from overpumping in coastal areas and allowing the seawater to move into the aquifers or in mining areas where you find acidity and issues or legacies of mining like acid mine drainage.”
Read more in Daily Maverick: Water resilience: Aquifer and groundwater recharge solutions are essential to building future security
Deputy Water and Sanitation Minister David Mahlobo said that other groundwater issues were the ability to deal with climate change, the pollution of water resources, and the fact that South Africa was a mining capital of the world, which had affected the aquifers.
Mahlobo said the week-long convergence should not be just a talk shop, but a brains trust that will come up with solutions that benefit generations to come.
Water losses in the system
“We still have enormous challenges in our country, such as assurance of water supply, which has declined due to a number of factors. Communities can go for days on end without water supply, and this is caused by our neglect of operation and maintenance of our infrastructure.
“Because we have not invested in operations and maintenance, we are experiencing a lot of water losses in our system — between 30% to 45%. The other challenge is the lack of investment in our infrastructure that matches the population growth and migration from other countries and people moving from rural to urban areas,” Mahlobo said.
Groundwater should be managed so it can provide sustainable water over the years.
This is especially true with the climate crisis, which will see South Africa and other countries relying more on groundwater.
Gladness Mohale, a hydrogeologist at the Council of Geoscience, said, “In most regions, groundwater is being utilised as an augmentative measure, in case of unavailable water from the surface water supply — so it always comes in conjunctively to release the pressure that surface water is failing to provide. With time, increased demand, and the issue of climate change, surface water is proving to be unreliable and unsustainable.”
The City of Cape Town’s Badroodien said groundwater plays a critical role in sustaining ecosystems and the environment by providing a continuous source of water to wetlands, rivers and estuaries, preserving vital habitats and supporting biodiversity.
“By maintaining these ecosystems, groundwater contributes to Cape Town’s overall ecological resilience, helping to protect against the adverse effects of urbanisation and ensuring that the city remains a sustainable and habitable place,” he said.
Groundwater is a cornerstone of the City of Cape Town’s water strategy. Badroodien said the ability of groundwater to provide a reliable and high-quality water source, especially during ongoing water challenges like droughts, helps secure the city’s water supply while maintaining ecological health and sustainability. DM