Gauteng is grappling with significant water challenges, as residents in Tshwane and Johannesburg confront the mounting pressures on the province’s water supply.
The No Drop report says physical water losses — that account for 33% — can be attributed to widespread leaks, illegal water connections and unregulated water use. Municipalities have been urged to enforce bylaws, repair leaks, and combat illegal activities that worsen the pressure on the system.
Worsening the problem at night is higher pressure levels, commonly referred to as the Bernoulli effect. This is according to Dr Chris Herold, a hydrologist and former president of the SA Institution of Civil Engineering (SAICE).
Herold explains this pressure surge results in even more water loss during night-time hours, as higher pressure worsens leaks.
“Because leakage is even higher at night, we have a serious problem filling our reservoirs at night since half of the water pumped into the reservoir is uselessly lost to leaks.”
Higher pressure causes more pipe bursts. Herold points out that the situation was not unlike the drought of 1982, when Joburg faced huge pipe bursts due to high pressure under water restrictions.
“In the 1982 drought, we had level 2 (30%) water restrictions. The Joburg municipality experienced eight times the average number of pipe bursts due to higher pressure. We are currently seeing more leaks than back then, and this isn’t even a drought.”
Alongside supply issues, water contamination is a serious concern. When pipes are emptied for repairs or due to restrictions, contaminants can enter the system.
Herold explains: “When the pipes are running full, leakage is out of the pipe, which is fine from a water quality point of view, but when you empty the pipes, bacteria can enter in the opposite direction.”
A recent incident at the Honeydew reservoir serves as a stark reminder: a broken pipe allowed soil to wash into the water system, causing contamination in downstream areas.
Herold warns of even more insidious risks: “Aside from the ingress of contaminated groundwater when pipes are depressurised, you can also get cross-contamination between leaking sewer pipes and water pipes and that’s when you have to be careful.”
He advises the public to be cautious when water supplies resume after an interruption. “You can use the water for boiling, but wait a bit before drinking from the taps again,” he says.
“The desperate practice of closing reservoir outlets every night time in an attempt to reduce water leaks is generally counterproductive since when the supply is restored each morning the air in the empty pipes can be compressed and break out weakened areas of old pipes and loosen the joints between even new pipes,” he says.
Additionally, this air can cause false meter readings, leading to inflated water bills for consumers.
While these infrastructure and contamination concerns are alarming, residents of Gauteng can take some solace in that a “day zero” scenario — where no water is available — does not appear imminent.
According to Muller, “there is no danger of a day zero in Gauteng for the foreseeable future”. However, he is quick to add that this security is contingent on municipalities stepping up their efforts to manage the system more effectively.
Prof Mike Muller from Wits University’s School of Governance says to avoid supply interruptions municipalities must reduce water leakage and ensure that they monitor and manage water use and that water restrictions are obeyed.
“Water users must avoid wasting water, fix leaks on their own premises and report leaks in the public system,” Muller says.
Now we’re hitting the iceberg and we may not have enough time to avoid sinking.
— Dr Chris Herold, a hydrologist and former president of the SA Institution of Civil Engineering
Water boards such as Rand Water focus on bulk supply and infrastructure at a regional level, while municipalities manage local distribution, maintenance, and customer interaction. Together, they aim to ensure efficient water service delivery, though this collaboration is showing signs of strain.
While this paints a grim picture, Muller says: “Gauteng is not running out of water — the dams of the Vaal river system are 74% full. However, Gauteng municipalities are using more water than they have been allocated.”
Muller points out that municipalities have the power to regulate water usage and enforce conservation measures but have not exercised this authority effectively.
As Gauteng’s population grows, the pressure on the water system increases. More people mean more taps, but unfortunately, a portion of water is lost to leaks. Additionally, many users aren’t metered or billed, giving them little incentive to manage their water use responsibly.
“I called it a crisis in 2008 and I was adamant about that because it’s like the Titanic,” Herold said.
“The crisis with our water system didn’t start when we saw the leaks. It started decades ago when we didn’t address the infrastructure problems. Now we’re hitting the iceberg and we may not have enough time to avoid sinking.
“The effect of 33% water leakage makes it difficult to achieve level 1 water restrictions,” he says.
“This issue also has a significant impact on the city’s ability to fill its reservoirs during hot weather, when water consumption spikes and reservoirs are drawn down to meet demand.”
Update: October 21 2024
This story has been updated with new information.
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