Engineer Phil de Jager’s plan to rescue Gauteng’s polluted Hennops and Jukskei rivers involves those living close to the waterways, technology and even a tunnel from the Vaal Dam.
The CEO of Archangel Special Projects says these rivers, once the lifeblood of Gauteng’s industrial heart, have turned into “open sewers running through residential areas”. But where most see an ecological write-off, he sees an economic opportunity.
That means installing physical traps, interception systems — and that tunnel.
The plan would deploy modular, containerised wastewater treatment units at the worst parts of the river corridor and use nano-bubble aeration technology.
The technology pumps oxygen into polluted water using bubbles so tiny they are invisible to the naked eye. Unlike normal bubbles, which rise and pop almost instantly, nano-bubbles stay suspended in the water for hours, slowly releasing oxygen.
The Jukskei and Hennops are essentially suffocating. The bacteria in them — nature’s decomposers — are starved of oxygen and can’t break down sewage. Nano-bubbles reverse that. They raise oxygen levels, allow natural clean-up bacteria to thrive, suppress the organisms that cause foul smells and create conditions where aquatic life can return. The equipment is compact and relatively low-cost, making it practical for riverside deployment.
De Jager wants to build three large recycling plants at Tembisa, Kya Sands and Hammanskraal.
Illegal dumping happens largely because legal disposal is expensive. His solution is to make waste worth money. Residents bring sorted waste to the plants and get paid for it. The economics of dumping flip overnight, he says.
And, instead of conventional replanting, De Jager wants alternating rows of industrial hemp and rose geranium planted along degraded riverbanks and buffer zones.
Hemp holds the soil, stops erosion and produces commercial fibre. Rose geranium pulls pollutants out of the ground and produces a valuable essential oil. Both crops generate income, particularly for riverside communities. The river becomes a source of livelihoods instead of a problem to manage, he says.
We cannot recycle ourselves out of the plastic pollution crisis
— Samiksha Singh
For long-term water security, he proposes a gravity-fed tunnel running from the Vaal Dam to Centurion Lake; the dam sits about 50m higher. Built on a single gradient so it requires no pumping, this tunnel would deliver clean water directly into the Crocodile West catchment — a system that supports 5.5-million people and 20% of South Africa’s GDP.
In his proposal, “From Pollution to Prosperity”, he argues that a “societal reset” could transform these toxic liabilities into economic engines. It’s a bold claim, given that for people in the catchment, the reality is a “nightmare of health issues, sanitation issues and loss of dignity”, he says.
At a recent clean-up, he says, organisers “explicitly told everyone not to even touch the water”. He points to tributaries from Tembisa, Ivory Park and Kaalspruit, where pollution ranges from plastic to sewage runoff and industrial chemical waste. Every day “forever chemicals” from toiletries add more toxicity.
The ecological collapse, he says, is visible: “Fish die-offs, destruction of wetlands, loss of bird and aquatic life habitat, water hyacinth invasions downstream, sediment accumulation, groundwater contamination, loss of biodiversity, increased flood risk, collapsing riverbanks.”
Samiksha Singh, a researcher at the Gauteng City-Region Observatory, a research and data institution, warns that the unseen danger may be more insidious. “River systems are the main transport pathway of microplastics,” she says.
“We cannot recycle ourselves out of the plastic pollution crisis,” Singh says. Recycling plants and community payments may monetise waste, but they are “only a short-term stopgap”. They fail to address the source. Policy must first confront “our heavy reliance on single-use plastic and inadequate waste management programmes”.
Jo Barnes, a lecturer in global health at Stellenbosch University, is blunt: “The single greatest driver of the widespread pollution … is the massive failure of local authorities to do proper upkeep and maintenance of their water and sanitation systems.
“It’s impractical to expect people living in low-income areas to avoid contact with the widespread contamination in their neighbourhoods.” Officials often blame residents, but “they all face poor services that contribute to their health risks”.
Failures in solid waste removal leave piles that block drains and trigger sewage spills. “Our local authorities need serious oversight, guidance and proper management,” Barnes says. “So far, the efforts to correct the failures have not met with notable success.”
Alanna Rebelo, a researcher at the Agricultural Research Council, adds: “Take care of the wetlands and respect them and you will reap the benefits.”
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