Jozi City Feature

What lies beneath

Water-what lies beneath the CBD

Searching for gold, miners tried to make it big in the central business district of Johannesburg. Today, miners have been replaced by small business owners who are also trying to make it. Unfortunately our mining past is the cause of water problems and radioactivity in the CBD today.

For Silence Dread (25), owner of Knox Hair Salon in Newtown, water is very important for his business. He is vocal on the subject of water conservation and the need to protect this precious resource. He explains that, before they can begin work on a client’s hair, they need to “prepare” them with water.

“Water is life, so without water there is no life. Without water there is no job for me and without water there is no food.

“Remember, for us to breathe, for the trees to have food, there needs to be water. Evaporation, condensation, rain falling – and then there is life, there is happiness, there is healthy clean living.”

Humans can only survive for about five to seven days without water. It is significant that the waters of the Witwatersrand are losing the ability to perform life-giving functions. This is caused by many factors, including acid mine drainage (AMD), bad conservation and limited resources.

The present: Where are we now?

The water situation in Johannesburg seems bleak when speaking to experts about acid mine drainage, water supply and radioactivity.



Water running into the street in the CBD.


“These problems are slow-onset disasters,” said Dr Anthony Turton, vice-president of the International Water Resources Association. He said these problems were the equivalent of the tsunami in Japan, but they are happening at a slower pace.

“Yes, it [South Africa’s tsunami] has hit us, but it is being felt by the poor and vulnerable, so it is not registering yet, as their voices are lost in the noise that accompanies the daily grind of poverty.”

On the other hand, Tebatso Matsimela, manager in marketing and communications at Johannesburg Water (JW), said there was no crisis situation. But he did acknowledge that South Africa was a water-scarce country and that “Johannesburg is not immune from this scenario”.

Key to understanding the water supply in Johannesburg, including the CBD, is to be aware the city does not have its own source of water. The city buys all its water from Rand Water. This water has to be pumped almost 80km from the Vaal River and lifted about 250m to get it to Johannesburg.

Donovan Reid, the Gauteng master licence holder of Water Rhapsody, a water conservation company, said water supply was a big issue.

“We have a pot of water and there is only so much water in the pot,” Reid said about the limited water supply in Johannesburg.

“Johannesburg is constantly growing and booming … yet no additional infrastructure has been added in the last few years.”

Johannesburg Water’s Matsimela said infrastructure upgrade projects were launched in 2008 to upgrade the “ageing infrastructure across the city”.

“We did a study to identify problematic areas … we were able to determine the capital needed to address the problems, hence the upgrading of infrastructure in phases.”


Infrastructure upgrades by Johannesburg Water in Harrison Street in the CBD.


Acid mine drainage causes another problem, namely radioactivity. AMD creates toxic water with a pH of 2, making it as sour as lemon juice, but with destructive consequences to humans, animals and the environment. Because the AMD is so sour, any heavy metals in the shafts and surrounding rock, through which the AMD rises, is mobilised and travels in the water.

Heavy metals such as uranium and radon get dumped into the river systems, wetlands and vegetation. This is another reason why AMD is hazardous to all forms of life – because of these high concentrations of heavy metals, said Philip Hobbs, research hydro-geologist at the Council for Scientific and Industrial Research (CSIR).

Uranium causes radon and radon gas to push up out of the open mine shafts. Not only are these gases toxic but the mine dumps become radioactive, because they contain high levels of radon.

The department of minerals and energy published a strategy report in 2008 for the Central Rand Goldfield and focused on radioactivity in the area. Not surprisingly, the mine dumps and sludge dams have elevated levels of radioactivity. What is worrying, though, is the migration of radioactivity levels from the mine dumps to the CBD.

According to the report, this migration has occurred because there has been increasing use of “mine dump and waste materials for building purposes”. Mariette Liefferink, CEO of the Federation for a Sustainable Environment, said these materials had been used to make bricks for buildings and materials to build roads, such as the M2.

However, Matsimela from Johannesburg Water says he is not aware of any radioactivity in the CBD.


Traces of radioactivity in the CBD. Radioactivity information obtained from Council for Geoscience report 2008-0174. Graphic by Mignionette de Bruin

Problems also arise when these radioactive materials from the mine dumps connect with water, causing seismic activity like earthquakes and possibly sinkholes, according to a 2010 task team report.


Information on seismic events obtained from report to the inter-ministerial committee on acid mine drainage. Graph by Mignionette de Bruin


Another issue the CBD currently faces is pollution from the toxic water flowing out of the mines. Liefferink explained: “Because our mines are above our rivers and not the other way around, as in many other cases, the pollution caused by the mines is being directly deposited into our water.”

This water, also called ground water, flows under the surface of the city and is Johannesburg’s only real source of water. Dr Francois Durand, a zoology and palaeontology lecturer at the University of Johannesburg, said: “The impact of AMD on ground water … is even worse than that on surface water bodies. Pollutants remain stagnant in ground water for many years, whereas pollutants may be flushed from rivers during heavy rains.”

Acid mine drainage also causes vegetation to die, animals to be malformed and humans to get cancer.

Dorothy Tang, an assistant professor at the University of Hong Kong, and Andrew Watkins, an architect and urban designer in Southern California, did a study on the gold mining and acid mine drainage (AMD) in Johannesburg in February 2011.

They said it was no longer financially viable for mining companies to pump AMD out of the mines since deep mining had ceased. Because pumping in the mines had halted, the polluted ground water rose at about one metre per day and, at this rate, experts said acid mine drainage would surface in Johannesburg next year.

It is important to understand that there is a void beneath Johannesburg – created by past mining activity – and this void plays a role in the process of AMD filtering into our water.

“Under Johannesburg there is a mine void five times the volume of Lake Kariba,” Turton said.

Durand explained that acid mine drainage reached our ground water by filtering through the rock above the mine void and by leaking from the mine dumps. Liefferink also explained that the rock above the void was porous and therefore the AMD seeped through easily.

There are three basins in the Witwatersrand: the Central Rand, Western and Eastern basins. In the Western basin the AMD is already overflowing and has been overflowing since 2002. This means about 30 to 60-million litres of AMD are flowing spontaneously onto the surface every day.

The Central Rand basin, where the CBD is located, has rising levels of AMD and Liefferink said they suspected the AMD levels were rising by 13 to 15 metres per month. The Central Rand basin is about 400 metres from overflowing and Liefferink said experts suspected this might happen in the next year or two.

If it does start overflowing it will do so at about 60-100 million litres per day. That is about 44 times the amount of water an 18-hole golf course consumes per day. Experts expect it will flow into basements in the CBD and Gold Reef City’s mines first.

Many years ago President Paul Kruger aired his fears when he said: “Instead of rejoicing you would do better to weep, for this gold will cause our country to be soaked in blood.”

Liefferink mirrored this response: “We have basically sacrificed our pure water sources for gold. It has now become our curse.”

The problem with AMD infiltrating our water systems is that it ends up flowing into the rivers which lead to the Vaal Dam, where Rand Water gets Johannesburg’s water from. The chance of our drinking water becoming contaminated is increasingly possible.

How acid mine drainage is formed. Graphic obtained from State of the Susquehanna.
With AMD filling up the mine void under the CBD, the danger of it contaminating the ground water and therefore boreholes is very high. In the end this all comes down to expensive solutions, which leads to unaffordable water.

Once this “tsunami” has struck us, the people most affected by the water crisis will unfortunately be the poor and most vulnerable, just as Turton described. This is mainly because the higher the costs to treat the water, the more expensive water will become. Also, the more water sources become contaminated, the scarcer water becomes, which will also increase its price.

The past: How did we get here?

Johannesburg was established in 1886 when gold was discovered on the farm Langlaagte on the Witwatersrand. Witwatersrand literally means “the ridge of white waters” in Afrikaans.

When settlers first came to Johannesburg they named many of their farms after the streams of water running over the rocks, such as Braamfontein and Doornfontein.

Johannesburg is situated on the Witwatersrand ridge, which divides the water supply to the north and south. In other words, it is the dividing point for water flow between the Limpopo and Vaal rivers.

This also causes the rainfall to the north of this divide to flow into the Indian Ocean and rainfall to the south of the divide into the Atlantic Ocean.

Johannesburg is not located near any major water sources which made it a strange place for a city to be established.

Two of Africa’s biggest rivers, the Limpopo and Orange, supply Johannesburg with its water. This also includes the Vaal River and Vaal Dam.

People from all over streamed to the city of gold with hope for a better life and a brighter tomorrow. Instead the mining brought sorrow to South Africa as the Second Boer War broke out because of the gold in 1899.

Despite Kruger’s warning about the gold, people continued to mine the Witwatersrand for all it was worth. For a century about 120 different mining companies took advantage of the gold and the environment of Johannesburg.

When the gold on the surface was exhausted and miners could no longer access the gold with only a pick, they went deeper into the earth’s surface with more complex methods. This is also where Johannesburg’s most precious resource lay – its underground water source.

“Johannesburg’s mines were and are on the surface and the rivers are underneath them, unlike in many other places,” said Liefferink. She has been very involved with the AMD crisis in the Witwatersrand.

The mining companies that went out of business in the following years, left big problems for future generations by leaving old mine shafts open and with direct access to the surface.


Mining effect on rainfall drainage. Graphic obtained from GRID-Arendal.

So are there solutions to this “curse” we have brought upon ourselves? We need to consider our future and in which direction Johannesburg should go to preserve its water for the future generations.

The future: How do we move forward?

The future of Johannesburg and its CBD’s water lies in wise decisions we and our government make from today.

Donovan Reid from Water Rhapsody said recycling systems and water demand management were some of the solutions.

“People are not being forced to save water and until [water] limitations are forced on them, they will not change.”

The University of Johannesburg and the University of Witwatersrand have both installed rainwater harvesting and grey water recycling systems from Water Rhapsody. Reid was also involved with the water systems at a project called the Early Learning Centre in Cosmo City which was headed by students from Cornell University in the USA.

“The water crisis is bigger than Eskom. It is a very big challenge,” Reid said.

The government has put initiatives in place to solve the AMD crisis. Government appointed the Trans-Caledon Tunnel Authority (TCTA) and other task teams like the 2010 task team, who have come up with the solution of neutralisation. This involves adding a huge amount of lime to the water in order to increase its pH level and remove the heavy metals from the water.

However, Liefferink said this solution was short term and somewhat inadequate. She said when lime was added to AMD it performed its function, but the water remained toxic due to the high level of salts in the water.

The Vaal Dam, one of Johannesburg’s main sources of water, already contained so much salt that by 2014 it would be impossible to treat the water, Liefferink said. If the Vaal Dam’s water became unusable, there would be water shortages in Johannesburg and water would become increasingly expensive

Liefferink and her team suggest an alternative solution called desalination, which is more expensive but, she said, it would have better long term effects. Desalination is when the salts are removed from the water to make it suitable for consumption.

Former minister of water and environmental affairs, Buyelwa Sonjica, gave funds towards neutralisation in 2010, but they ran out after two months. Now the TCTA and the task team are saying they need more capital, but it seems the National Treasury simply cannot afford the funds for medium or long term solutions.

The task teams report in December 2010 stated that the Central Rand basin needed a pump with the capacity of 60 million litres per day in some of the existing mine shafts. They also recommended a neutralisation plant for short term purposes and desalination for the longer term.

Professor Terence McCarthy, a lecturer at the school of geosciences at Wits, stated in a 2010 report: “The solution to the problem is relatively simple… [It] involves the establishment of pumping stations to pump the water to the surface for basic treatment.”

McCarthy suggested old mine shafts be refurbished to access the ground water with at least two of these pumps as “it is cheaper to pump water from 300m below the surface of Johannesburg than to pump it to the city from Vaal Dam”.

He also said Johannesburg needed to be proactive about the AMD situation: “The sooner we move the economy onto a sustainable (environmentally, socially and economically) footing, the sooner we will find long-term solutions to our problems…”

Even though Johannesburg is facing major challenges we can all contribute something to ensure its water lives a long and healthy life.

Water saving tips

No blockages – Don’t dump foreign objects, oil, grease or building materials into the sewer or drains.

Be tap smart – If you leave the tap running while brushing your teeth, you waste up to eight litres of water per minute.

Be quick about it – If you shower for only five minutes, you save almost 400 litres of water per week compared to bathing. That is the amount of water it takes to make 32 teaspoons of sugar.

Fully committed – One full load of washing uses about 95 litres of water, which is still less water than two half loads would use.

Going green – Grow your grass longer as it will stay greener than a mowed lawn and need less water.

Get your hands dirty – Use your fish tank’s dirty water to water houseplants … It’s an excellent fertiliser.

Keep cool – If you need cooler water, save water by turning the hot tap down instead of the cold one up.

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About Mignionette de Bruin

Mignionette completed her undergraduate degree in financial journalism at the University of the Free State in 2010. She then went on to do her honours degree in journalism and media studies at Wits University. She specialised in photojournalism, but fell in love with editing and designing. This is also the direction in which she hopes to steer her career after university. Brilliant photography excites her as well as the thrill of editing an article to near perfection.

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