Urine to fertiliser could help solve South Africa’s Wastewater Crisis
Experts highlight urine-to-fertiliser innovation as a sustainable solution to municipal water strain and infrastructure decay.
By Larry Claasen
THE growing water crisis in South Africa should drive the country to consider novel approaches to dealing with it like turning urine into fertiliser, says Dr Jeffrey Baloyi, senior chemical engineer, Council for Scientific and Industrial Research (CSIR), South Africa.
Speaking at the Big 5 Construct South Africa’s 13th Expo in Johannesburg, Baloyi said urine should not be seen as waste but rather as a resource, and pointed to how it contains phosphorus and nitrogen, which are key ingredients for fertiliser.
He gave an example of how the private sector can not only alleviate the crisis if urine is separated at the source – a building – but also stood to gain financially because they could sell it for use as an ingredient in fertiliser.
Baloyi said the CSIR had conducted an extraction pilot and found that the separation of urine could eliminate 75% of nitrogen and 55% of phosphorus from municipal wastewater. He added it could do this at a fraction of the cost of conventional treatment, and that recovered fertilisers achieve results comparable to or better than those of chemical fertilisers.
The science of struvite synthesis
The best way to extract the phosphorus and nitrogen is via struvite synthesis, which is the process of adding magnesium to urine and adjusting its pH level. This process will crystallise dissolved nutrients into a slow-release fertiliser.
At the same time, it will preserve the water infrastructure as it will prevent pipe-clogging ‘struvite rock’ from forming. By preventing the build-up of struvite rock, it reduces the possibility of costly plant shutdowns and also turns a waste headache into a valuable product.
Baloyi said the maintenance cost of dealing with struvite rock is huge for a water provider.
“It takes more than a month to get a section back.”
This type of maintenance also has an environmental impact, because when treatment is reduced, raw or partially treated wastewater is diverted, causing pollution in other areas.
Water systems at a critical juncture
The potential of turning urine into fertiliser should also be seen against a backdrop where South Africa’s water infrastructure is under strain.
The 2026 Blue Drop Progress Report found that South Africa’s wastewater treatment performance has declined, with only 16 systems achieving Green Drop Certification in 2024, down from 23 in 2021. At the same time, nearly half of all municipal wastewater systems assessed – 396 out of 848 – are now in a critical state.
“These results confirm what communities have been saying for years. The crisis is not new – what is new is the continued failure to act. Reports are being released, but where is the accountability?” asked WaterCAN executive director, Ferrial Adam.
Baloyi warned that if maintenance was not prioritised, the cost to the country would be huge.
He made the point that recovering nutrients and reusing water lowers overall costs. By bringing in the private sector, municipalities can save on maintenance, and those savings can be shared with the solution provider.
UCT spin-off scales up the solution
Baloyi is not the only scientist looking to turn urine into fertiliser. A group of scientists from University of Cape Town (UCT) have spun out their research on the matter into a company, PeeCycling.
Founded by Professor Dyllon Randall and Dr Caitlin Courtney, PeeCycling has developed an engineering system for commercial-scale resource recovery plants for urban and industrial environments.
According to its website it has successfully processed 3,200 litres of urine per day.
“This localised production creates a sustainable, circular supply chain that reduces the carbon footprint associated with both synthetic fertilizer manufacturing and conventional wastewater treatment,” it said.
It added that for every litre of urine processed, its system recovers about 700 mL of water that could be reused for non-potable applications, such as irrigation or industrial cooling.
“By capturing and recycling this water on-site, we prevent the loss of significant volumes of municipal water, building vital resilience for high-traffic facilities in drought-prone areas,” said PeeCycling.
PeeCycling was shortlisted for an Africa Prize for Engineering Innovation by the Royal Academy of Engineering earlier this year.
