The Cape Navigator

Seaside Community Newspaper

Cape Town

Chemical Concerns Addressed in R5 Billion Wastewater Reuse Plan

Michael Hawthorne

The City of Cape Town (CoCT) is moving forward with a controversial R5 billion plan to transform sewage effluent into drinking water. However, environmentalist groups and concerned citizens fear that current water safety standards do not adequately address a wide range of potentially harmful chemicals present in wastewater.

Concerns About PFAS and SANS241

The Facebook page Bay of Sewerage and other groups have drawn attention to the fact that South Africa’s drinking water standard (SANS241) does not include testing for over 15,000 chemicals, including Per- and Polyfluoroalkyl Substances (PFAS). PFAS are industrial chemicals linked to serious health conditions and are particularly concerning because they persist in the environment, often accumulating in sewage.

City of Cape Town Responds

Councillor Zahid Badroodien, a Mayoral Committee Member for Water and Sanitation, insists that the City takes these concerns seriously. He highlights that SANS241 calls for a risk-based approach, going beyond the minimum requirements by using World Health Organization (WHO) guidelines to assess potentially harmful contaminants.

The City confirms that PFAS have been identified as a risk. In response, they’ve designed an advanced purification plant using Granular Activated Carbon (GAC) filtration, a technology intended to remove PFAS. An independent panel of international experts will advise and monitor the project over the next decade.

Testing and Transparency

The City maintains that extensive testing will detect PFAS and other chemicals of concern, regardless of their inclusion in SANS241. They plan to make water quality results publicly available.

Alternative Solutions and Public Consultation

Critics question whether the City has fully explored alternative water augmentation strategies that may be less chemically intensive. The City responds that its Water Strategy aims for resilience by diversifying water sources and that the wastewater reuse plan has been carefully designed with sustainability in mind.

The City of Cape Town acknowledges the importance of public trust, asserting they’ve engaged with various stakeholders and welcome further dialogue to proactively address concerns.

Questions Answered by Councillor Zahid Badroodien, Mayoral Committee Member for Water and Sanitation

Q: The organization ‘Bay of Sewage’ and other anti-effluent groups have expressed serious concerns about the ‘water reuse’ project, stating that SANS241 water standards do not test for over 15,000 potentially harmful chemicals, many of which concentrate in sewage effluent. How does the City intend to address these specific concerns and assure the public of the safety of ‘reused’ water?

A: The existing SANS 241:2015 drinking water standard prescribes numerical limits for a list of parameters that provide the minimum assurance necessary that water presents an acceptable health risk to consumers for lifetime consumption. However, beyond these minimum requirements, the standard also requires the adoption of a risk-based approach to consistently ensure the supply of safe drinking water and requires that a risk assessment be conducted to identify hazards that are not explicitly listed. SANS 241:2015 further stipulates that identified hazards not listed must comply with values stated in the internationally recognised World Health Organisation’s (WHO) Guidelines for drinking water quality.

The City of Cape Town is fully aligned with all requirements of the standard by adopting the risk-based approach, which is supported by comprehensive water quality testing of the water source for potentially harmful contaminants. These contaminants include pathogens, heavy metals, herbicides and pesticides, pharmaceuticals, personal care products, radionuclides, PFAS, disinfection byproducts and other contaminants of emerging concern. The City has assessed the concentrations of identified contaminants against the WHO guidelines and other international regulatory limits and guideline values to assess and address the risks.

The new SANS 241 does include per- and polyfluoroalkyl substances as an Annexure and not yet as Mandatory determinants. This is an approach to encourage the country to start preparing for this type of analysis, which may become mandatory in the next SANS 241 revision.
The City’s Scientific Services Branch has already purchased the necessary equipment which can analyse for a number of contaminants of emerging concern, and is engaging with various academics and researchers to establish testing procedures and protocols.

Q: PFAS Concerns: PFAS (“forever chemicals”) are widely used, persistent in the environment, and linked to serious health conditions. How will the City’s ‘water reuse’ project specifically address and mitigate the risks of PFAS contamination in the drinking water supply?

A: The group of per- and polyfluoroalkyl substances, collectively known as PFAS, were identified in the water source as part of the comprehensive water quality risk assessment and found to be present at levels that exceed recommended international limits. The advanced purification plant is therefore specifically designed to reduce the PFAS concentrations to safe levels. This is achieved through a process known as Granular Activated Carbon (GAC) filtration; a proven technology for the effective removal of PFAS.

An independent advisory panel (IAP) of international reuse experts was established to interrogate and challenge the City’s approach to implementing potable reuse. The IAP members have been providing feedback and guidance over the last three years and have been instrumental in ensuring that the City’s approach, including the risk assessment and water quality testing campaigns, is in alignment with international best practices. The City intends to extend the IAP members’ involvement for the next 10 years to cover the construction and commissioning of the advanced purification plant.

Q: Testing and Monitoring: What specific testing and monitoring protocols will be in place to detect PFAS and other chemicals of concern that are not covered by the standard SANS241? Will this testing be made publicly available?

A: The risk-based approach that has been adopted by the City of Cape Town is underpinned by the principles of the Hazard Assessment and Critical Control Point (HACCP) process; widely used in the food and beverage industry for protecting consumers from acute and chronic health risks. Under the HACCP process, each treatment process within the Faure New Water Scheme has been rigorously assessed in terms of its ability to address the identified health hazards. Through this process, Critical Control Points (CCPs) within the scheme have been identified that are integral to ensuring the adequate removal of contaminants from the water source. The performance of the CCPs will be monitored online 24/7 and will automatically and immediately divert contaminated water that falls out of specification.

The online monitoring throughout the scheme will be supplemented by laboratory testing to demonstrate compliance in terms of SANS 241-listed parameters and in terms of health hazards identified through the risk assessment. The City of Cape Town currently publishes drinking water quality results for all its water supply sources on an annual and quarterly basis on its website.

Q: Alternative Solutions: Given the concerns about existing water standards and PFAS contamination, has the City explored alternative, potentially more sustainable, and less chemically intensive methods of water augmentation?

A: The City’s current Water Strategy has specifically been developed to build resilience into its water supply system. This will be achieved by augmenting the current supply with new water sources that are not as dependent on rainfall for replenishment. The New Water Programme (NWP) intends to diversify the City’s portfolio with a blend of groundwater and small springs, water reuse, and desalination schemes. Among this suite of new water sources, water reuse has emerged as both cost-effective and having a net-positive impact on the environment. This is intentional, and confirms the City’s commitment to ensuring sustainable practices, as the treatment processes have been carefully selected for their ability to remove contaminants from the water cycle, rather than concentrating and diverting contaminants elsewhere within the cycle.

Q: Public Consultation: How will the City be addressing the concerns raised by concerned citizens and organizations, and ensuring transparency and public trust in the ‘water reuse’ project?

A: Over the past five years, the City of Cape Town has engaged different stakeholder groups including political and governmental organisations, religious organisations, businesses, academia, environmental groups, public health organisations, regulatory bodies and the scientific community across various forums. We have responded to countless written queries from residents and given comment in articles by the mainstream media.

The City has regularly updated the public on its plans via its website and the Water Outlook reports. The City plans to expand this process to proactively seek public concerns and to plan properly to ensure the safe supply of drinking water for all Capetonians.

Other Sources

What is Cape Town’s plan for water reuse?

New water reuse plan for Cape Town


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