AfriPulse
Ecologically stressed: The
Jukskei River has been choked by
pollution, encroaching informal
settlements in flood-prone zones
and ageing water infrastructure.
Photo: Supplied
Johannesburg could save millions of rand in infrastructure damage, healthcare costs and environmental management by investing in nature-based solutions to restore parts of the degraded Jukskei River, turning one of the city’s most troubled waterways into a frontline defence against climate risk.
An economic analysis of climate adaptation work under way in the Jukskei River catchment found that every dollar invested in restoring ecosystems such as wetlands and green spaces generates more than three dollars in economic, social and environmental benefits.
The findings, part of new research by the International Institute for Sustainable Development (IISD) and the World Resources Institute (WRI), form part of the Scaling Urban Nature-Based Solutions for Climate Adaptation in Sub-Saharan Africa (Suncasa) initiative, launched in May 2024.
As cities grapple with tightening budgets and intensifying climate shocks, the study makes a clear financial case: restoring nature is not only an environmental imperative but an economically viable form of infrastructure.
By 2050, nature-based solutions implemented in Johannesburg could generate significant savings for the city. The report estimates that investments in restoring the Jukskei catchment could help the city avoid about $3.5 million (R57m) in flood-related infrastructure repairs; $2.2m in invasive alien plant management costs; and $4.83m (R78.6m) in health costs linked to water pollution, flooding and urban heat.
The research concluded that every $1 invested produces $3.06 in economic value — a return that underscores the long-term viability of nature-based climate adaptation.
The Jukskei River is one of Johannesburg’s most ecologically stressed river systems.
Flowing through densely populated urban areas, including Alexandra, it has been choked by pollution, encroaching informal settlements in flood-prone zones and ageing water infrastructure.
Covering roughly 772km2, the catchment faces mounting pressure from rapid urbanisation, worsening floods and droughts linked to climate change, erosion, sedimentation and declining wetland health. The overlapping pressures have reduced the river’s ecological resilience while increasing risks for communities living along its banks.
In many parts of the city, natural systems that once absorbed floodwaters, filtered pollutants and moderated temperatures have been damaged or lost. The result is a river system that not only reflects environmental strain but amplifies it.
To revive the catchment, the Suncasa project is implementing a range of nature-based solutions, which include removing invasive alien vegetation, planting indigenous trees, rehabilitating wetlands, restoring river buffer zones and expanding urban green spaces.
The interventions are designed to improve water quality, reduce flood risk, cool urban temperatures and restore biodiversity, while delivering social and economic benefits that are often overlooked in traditional infrastructure planning.
The Suncasa initiative, led by the IISD in partnership with the WRI and funded by Global Affairs Canada, is being rolled out in Johannesburg through a collaboration with the City of Johannesburg, Johannesburg City Parks and Zoo, the Johannesburg Inner City Partnership, Alexandra Water Warriors and other local organisations — a cross-sector effort spanning government, civil society and the private sector.
The project’s main objective is to support municipal governments, communities and other urban stakeholders to increase their resilience to climate-induced risks such as flooding, droughts and other water-related risks by adopting and implementing gender-responsive nature-based solutions.
Ecologically stressed: The Jukskei River has been choked by pollution, encroaching informal settlements in flood-prone zones and ageing water infrastructure. Photo: Supplied
What sets the new analysis apart is its use of a methodology known as sustainable asset valuation, which measures the full economic value of nature-based infrastructure. Traditional cost-benefit analyses tend to focus narrowly on direct financial returns, often missing the broader benefits provided by ecosystems — from carbon storage and job creation to improved public health and climate resilience.
By capturing the wider impacts, the study estimates that restoring the Jukskei catchment could generate about R152m in net economic benefits over 25 years, with a payback period of roughly seven years.
The financial case for nature-based solutions is driven largely by avoided costs: expenses the city would otherwise incur if environmental degradation continues unchecked. These include damage to infrastructure from flooding, rising healthcare costs linked to polluted water and heat exposure and the growing expense of managing invasive plant species.
The research says avoided costs amount to about R186m, more than half of which are tangible savings such as reduced infrastructure damage and lower spending on invasive species control. Additional benefits, including carbon sequestration and job creation, contribute a further R39.6m in value.
Importantly, many of the gains are widely distributed rather than concentrated. The benefits extend to roughly 2 000 direct participants and more than a million indirect beneficiaries across the city, reflecting the broad public value of restoring urban ecosystems.
Michail Kapetanakis, the economic and finance expert who led the study, said the positive economic returns associated with nature-based solutions in the city were driven by avoided health costs due to improved water quality, lower expenditure on infrastructure repairs as a result of decreased flood damage and savings in alien invasive planet management costs.
“In addition, the carbon sequestration benefits provided by nature-based solutions have a considerable added value. Collectively, these impacts support the long-term economic viability of such initiatives, particularly when assessed over a 25-year timeframe.”
The largest impact comes from avoided health costs linked to water pollution, flooding and urban heat — estimated at more than R65m over 25 years, highlighting how environmental degradation translates into human health burdens.
Flood damage to infrastructure follows closely, with avoided costs of more than R62m, while savings from reduced invasive plant management are estimated at nearly R39m.
Carbon sequestration — often overlooked in local planning — adds more value, with benefits estimated at more than R31m under current assumptions and significantly higher under alternative pricing scenarios.
Kapetanakis said the analysis challenged the perception that nature-based solutions were secondary to “hard” infrastructure.
“This analysis demonstrates that nature-based solutions should not be viewed solely as environmental initiatives but also as economically sound investments. Investing in nature generates long-term economic returns alongside essential ecosystem services. When cities invest in ecosystems and nature-based solutions, they unlock a broad spectrum of indirect economic, social and environmental benefits that are often overlooked in conventional infrastructure assessments.”
Although many of the benefits do not translate into immediate revenue, their long-term value is substantial. “The implementation of nature-based solutions along the Jukskei River in Johannesburg is expected to enhance the local ecosystem, delivering key benefits such as improved water quality and reduced flood risk,” he said.
The interventions also created an opportunity to foster gradual behavioural change by encouraging greater recognition, valuation and appreciation of ecosystems and nature-based approaches, he said.
“This shift in perspective is critical for enabling the broader adoption and scaling of nature-based solutions across Johannesburg or other urban contexts.”
The implications extend beyond Johannesburg. Across Africa, many cities face similar constraints: limited budgets, growing populations and increasing exposure to climate risks.
Kapetanakis said studies like this could helped unlock new forms of financing by strengthening the business case for nature-based infrastructure.
“The Suncasa project demonstrates the value of using grant funding to support investments in nature and biodiversity. Its outputs support municipalities in u
Source: Mg.co.za | Read the Full Story…
