Operating at the tail end of the heavily polluted Crocodile West River Catchment, Magalies Water is confronted with some of the country’s most compromised raw water matrix. But through internal control processes, science, innovation and a focus on source water security, the water utility continues to deliver safe, compliant drinking water.

Magalies Water abstracts its raw water from a network of interconnected systems in the Limpopo, North-West Province and parts of Gauteng, with its primary sources being four major dams: Bospoort, Roodekopjes, Vaalkop and Roodeplaat. These dams are fed by key rivers including the Hex River, Crocodile River, Elands River and Pienaars River. Together, these systems form part of the broader Crocodile West Catchment, which is one of the most economically active and heavily utilised water systems in South Africa.

“A defining characteristic of several Magalies Water’s abstraction points is that they are located downstream of the catchment system. This means the water has already passed through multiple upstream activities before reaching the dams. As water flows downstream, it carries the cumulative burden of runoff, industrial discharge and wastewater effluent from tributaries, urban areas and industries. By the time it reaches Magalies Water’s systems, the raw water is often significantly more polluted than upstream,” explains Phindile Mahlangu, scientific services manager, Magalies Water.

Diffuse pollution – the release of pollutants from widespread, varied activities rather than a single system – is also one of Magalies Water’s biggest challenges. Rapid urbanisation and the growth of informal settlements without formal waste management systems compound the issue. So does climate change. Drought conditions concentrate contaminants, while heavy rainfall events wash pollutants into rivers and dams through stormwater systems.

At the same time, the problem is being reinforced by failing wastewater infrastructure. Mahlangu adds that the recent Green Drop Report shows an even further decline in municipal wastewater treatment infrastructure.

“This has resulted in partially treated effluent being discharged into our systems.”

Hartbeespoort Dam

The effects of upstream pollution are precisely what Magalies Water is working to address through its appointment by the Department of Water and Sanitation (DWS) as the implementing agent for the Hartbeespoort Dam remediation programme, which forms part of the broader Crocodile West Catchment Water Resource Management Project. This work is not limited to the dam itself but extends across the entire upstream catchment.

“Any gains from upstream interventions ultimately flow back to us downstream, where we abstract the water, allowing us to clearly see both the impact of our efforts and the value of investing in the catchment,” explains Mahlangu.

At a catchment level, Magalies Water is undertaking water quality monitoring, pollution profiling and source tracking. This involves analysing water quality data to identify pollution hotspots and trace contaminants back to their origin, enabling the regulator to take enforcement action.

Within the dam itself, interventions focus on restoring ecological balance and improving water quality. This includes removing invasive aquatic vegetation, which thrives in nutrient-rich conditions driven by excessive nitrogen and phosphorus loads. These nutrients, largely from wastewater effluent, drive eutrophication, resulting in algal blooms, invasive plant proliferation and deteriorated water quality.

Magalies Water has also implemented in-lake treatment technologies, including nanobubble and bioremediation interventions, to increase dissolved oxygen levels and reduce nutrient concentrations. This technology is designed to improve water quality within the dam, although its effectiveness is constrained by the continuous inflow of polluted water from upstream.

Importantly, the organisation recognises that in-dam interventions alone are not enough. While remediation efforts can improve conditions locally, the long-term solution lies in reducing pollution at source, particularly by improving wastewater treatment performance in upstream municipalities and strengthening regulatory enforcement. Without this, the dam remains heavily polluted.

Integrated water resource management

This reality is also reshaping the role of water boards. Historically, water boards operated primarily as bulk suppliers.

“Water boards can no longer operate in isolation,” says Mahlangu. “We need an integrated approach across the entire water supply value chain, from source to tap.”

As a water board with strong research, development and innovation capacity, Magalies Water is well positioned to support municipalities with technical expertise, data-driven interventions and fit-for-purpose solutions to improve water quality and system performance.

“Magalies Water is increasingly involved in catchment management and remediation as well as municipal support. We aim to help resuscitate water systems at the water service provider or water services authority level. Magalies Water is assisting municipalities with Blue Drop compliance, process audits and the development of water safety plans and Incident Management Protocols. These systems take a holistic view of the entire water value chain, from abstraction and storage to pipelines and the consumer tap, identifying risks and interventions across the system. Bulk water supply is essentially at the beginning of the water value chain for municipalities, and we can help them identify further risks along the chain and optimise their operations,” adds Mahlangu.

Magalies Water regularly partners with municipalities and holds community engagement forums on water conservation and demand management, pollution and water quality. They also promote digitisation, smart metering and non-revenue water reduction, recognising that operational inefficiencies and water losses further strain already limited resources.

The rise of emerging risks

While traditional pollutants remain a challenge, a new threat is rapidly gaining attention: contaminants of emerging concern.

These include synthetic chemicals from everyday products that enter water systems through runoff and wastewater. Often unknown and difficult to detect, they require advanced analytical methods and specialised expertise.

“The challenge with emerging contaminants is that they are constantly evolving,” Mahlangu explains. “You first have to identify them, then understand their impact, and only then determine how to remove them.”

For a sector already under financial and operational strain, this adds another layer of complexity.

In effect, drinking water treatment plants are increasingly being forced to compensate for upstream failures, taking on a role they were never designed to fulfil. This has a cascading effect. Higher contamination levels drive up operational costs, increase energy consumption, and accelerate infrastructure wear through intensified strain. Treatment becomes less efficient, more complex and expensive.

“At Magalies Water, the output per unit, specifically energy and chemical spend, is increasing due to deteriorating raw water quality, which is forcing the plants to work harder while producing less. Previously, the same amount of energy and chemicals could reliably produce, for example, 50 Mℓ/day, but now, with higher nutrient, metal, and microbial loads, that same input may yield only a fraction of the original quantity of compliant treated water. Increased chemical dosages are required for treatment, maintenance is more frequent (due to source water eutrophication and system inefficiencies due to invasive plants), and yet the throughput must be reduced to safeguard water quality,” explains Mahlangu.

In simple terms, the cost per litre treated is rising because the system must use more energy and chemicals more often to maintain safe drinking water standards amid worsening raw water conditions.

Mahlangu gives an example: “Ammonia enters rivers and dams through partially treated sewage, industrial discharge and agricultural runoff. Many wastewater treatment plants are failing to effectively remove ammonia, and conventional water treatment works are not traditionally designed to remove it, so many systems are struggling. As a result, water treatment plants are forced to adapt, adjusting processes and, in some cases, introducing advanced treatment technologies just to keep water within safe limits.”

At the same time, ammonia interferes with disinfection processes. When chlorine is added to water containing ammonia, it forms chloramines, which are weaker disinfectants. If not carefully managed, this can compromise the system’s ability to control microbial contamination effectively.

Beyond the treatment works, ammonia plays another role, one that is visible to the public. As a nutrient, it fuels the growth of algae and cyanobacteria in dams and reservoirs. This process, known as eutrophication, leads to the familiar problems of green water, unpleasant tastes and odours, and, in some cases, the production of toxins. Systems like Hartbeespoort Dam have become well-known examples of how nutrient loading, including ammonia, can transform a water body into a highly degraded ecosystem.

The proliferation of alien invasive species in nutrient-rich water presents additional problems to bulk water suppliers.

“At raw water abstraction points, these plants accumulate at inlet screens, which are designed to prevent debris from entering the treatment works. Historically, these screens dealt with occasional natural debris, such as branches. Today, they are increasingly overwhelmed by dense mats of invasive vegetation. These screens constantly must be removed, cleared and put back,” says Mahlangu.

Managing the costs of water treatment

Compounding the technical challenge is the socio-economic reality of Magalies Water’s service area. A significant portion of the communities it supplies are indigent, which limits the utility’s ability to recover rising treatment costs through tariffs. This creates a difficult balancing act: as raw water quality deteriorates and treatment becomes more complex and expensive, the organisation cannot simply implement high-cost technologies or pass those costs on to consumers. Instead, it is forced to prioritise cost-effective, fit-for-purpose solutions that maintain compliance while remaining affordable, adding another layer of complexity to an already strained system.

The organisation is working closely with the Water Research Commission to develop technologies suited to South African conditions.

“We look for solutions that are nature-based, sustainable and cost-sensitive interventions, such as the adsorption and bio-remediation technology. Magalies Water researches and uses multiple technologies and interventions, as there is no silver bullet for water quality issues. Magalies Water is focusing on proactive maintenance to ensure our systems operate at the highest possible efficiency. We are also analysing all chemicals used in the water treatment system to ensure that all supplied chemicals are of the greatest quality,” states Mahlangu.

Compliance

Ensuring compliance with SANS 241 remains central to operations. Magalies Water has invested heavily in its scientific services, achieving approximately 98% accreditation of analytical methods under ISO 17025.

This enables the organisation to produce reliable, accurate water-quality data and maintain high standards of drinking-water compliance.

Supporting this are dedicated teams focused on process optimisation, research and development, and quality management, including ISO 9001 certification at an organisational level.

“Implementing ISO 9001 is a strong strategic move for a water utility because it embeds a structured, organisation-wide approach to quality, risk management and continuous improvement. At the same time, ISO 9001 strengthens governance through documented procedures, audit readiness and accountability, while building credibility with regulators, municipalities and consumers by demonstrating a clear commitment to delivering safe, reliable and high-quality water,” says Mahlangu.

She adds that South Africa has one of the best drinking water standards in the world. “Its recent amendments follow a risk-based approach, which enhances different risk categories for public safety, as well as catchment and system-specific compliance frameworks.”

Source water protection

For Magalies Water, the challenge is clear. It must continue to deliver safe drinking water under increasingly difficult conditions, while advocating for systemic change upstream. This requires collaboration across government, industry and communities, as well as greater public awareness of the value of water. “Our water systems are continuously being polluted,” she explains.

“The improvement of water quality at an impoundment level, but at the same time, more contaminants are entering the system.”

“Water is not just a commodity”, Mahlangu concludes. “It is a shared resource that underpins our health, our economic development and our future. Protecting it is everyone’s responsibility. People need to understand that what is discharged into the environment does not disappear. It returns, often in a different form, and often at a higher cost. What is done to water resources will ultimately be returned, in this instance, in the form of consumer costs and ecological disruptions.”