Bird’s Eye View

Collectively, Capetonians produce hundreds of millions of litres of grey and black waste water per day. This is water from bathrooms, kitchens, toilets, and other drains. It also includes liquid waste from hospitals and factories, some of which is highly polluted.

Sewer catchment areas of Cape Town (COCT website resources)

Waste water treatment cleans dirty water until it is safe enough to release back into the environment without affecting biodiversity or the health of nearby communities. It is the City of Cape Town’s responsibility to provide a functioning sewer network and effective wastewater treatment works that can clean the water until it can safely go into rivers, canals, vleis, aquifers, or the sea. National Government has set specific standards for treated waste water quality that need to be met by treatment plants, as well as other regulations relating to waste disposal into the environment.

However, most of Cape Town’s current wastewater infrastructure is old and has not been regularly upgraded to meet the needs of a rapidly increasing urban population, or the changing nature of sewage that contains new chemical compounds.

While some new upgrades have begun, not all communities have waterborne sewage. Inadequate sanitation services to informal settlements leads to regular raw sewage contamination.
In addition, the range of new chemicals and pharmaceuticals developed in the past few decades cannot be adequately treated by older water treatment processes. New pollutants need new treatment strategies.

Click here further information on all the different wastewater treatment facilities in Cape Town.

Wastewater Treatment Steps

Sewage and wastewater treatment processes have been categorised into three different treatment types: primary, secondary and tertiary treatment.

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Pre-treatment typically removes large solid materials from wastewater, including plastic, paper, rags, and leaves. Finer solid materials such as sand, grit, broken glass fragments and small stones are then removed by the physical process of filtration. In some cases, pre-treatment is simply maceration — breaking the solids and plastics up into tiny parts.
Primary treatment involves the process of sedimentation, during which relatively heavy solid materials settle at the bottom of a storage unit, from where they are removed from the wastewater stream. Other lighter components such as oils, fats, grease and other light solid materials float to the surface and are also removed. About two thirds of the waste content in the water is removed at this step, as measured by its biochemical oxygen demand (BOD). The primary-treated wastewater stream is either discharged as-is or treated further by secondary treatment processes.
Secondary treatment is mainly concerned with the removal of suspended and dissolved organic contaminants originating from human waste, soaps, detergents, etc. to further decrease the BOD.
This step is commonly carried out by naturally-occurring water-borne microorganisms in a controlled environment, using technologies such as activated sludge, bio-filtration and/or rotating biological contactors for the degradation of biological matter.
After secondary treatment, the separation of microorganisms from the secondary-treated wastewater stream is required prior to effluent discharge, or further treatment by tertiary water treatment processes.
Tertiary treatment (conventionally termed the “polishing” stage) involves further reduction in the organic compounds and microorganisms in wastewater streams. This step treats effluents well enough that they meet regulations governing the quality of water that is discharged into the environment (rivers, vleis, lagoons, canals, underground aquifers, and the sea). This water is also ready for re-use in agriculture, irrigation or groundwater applications.
Tertiary treatment includes processes such as chlorination, ozonation and ultra-violet (UV) radiation, that kill pathogens such as bacteria and viruses. In addition, physical separation technologies such as micro-filtration and synthetic membrane filtration remove microorganisms and fine particles from wastewater based on size.
More recent forms of tertiary treatment include advanced oxidation technologies to break up chemical pollutants — specifically organic chemical compounds — in wastewater streams.

Pre-treatment typically removes large solid materials from wastewater, including plastic, paper, rags, and leaves. Finer solid materials such as sand, grit, broken glass fragments and small stones are then removed by the physical process of filtration. In some cases, pre-treatment is simply maceration — breaking the solids and plastics up into tiny parts.
Primary treatment involves the process of sedimentation, during which relatively heavy solid materials settle at the bottom of a storage unit, from where they are removed from the wastewater stream. Other lighter components such as oils, fats, grease and other light solid materials float to the surface and are also removed. About two thirds of the waste content in the water is removed at this step, as measured by its biochemical oxygen demand (BOD). The primary-treated wastewater stream is either discharged as-is or treated further by secondary treatment processes.
Secondary treatment is mainly concerned with the removal of suspended and dissolved organic contaminants originating from human waste, soaps, detergents, etc. to further decrease the BOD.
This step is commonly carried out by naturally-occurring water-borne microorganisms in a controlled environment, using technologies such as activated sludge, bio-filtration and/or rotating biological contactors for the degradation of biological matter.
After secondary treatment, the separation of microorganisms from the secondary-treated wastewater stream is required prior to effluent discharge, or further treatment by tertiary water treatment processes.
Tertiary treatment (conventionally termed the “polishing” stage) involves further reduction in the organic compounds and microorganisms in wastewater streams. This step treats effluents well enough that they meet regulations governing the quality of water that is discharged into the environment (rivers, vleis, lagoons, canals, underground aquifers, and the sea). This water is also ready for re-use in agriculture, irrigation or groundwater applications.
Tertiary treatment includes processes such as chlorination, ozonation and ultra-violet (UV) radiation, that kill pathogens such as bacteria and viruses. In addition, physical separation technologies such as micro-filtration and synthetic membrane filtration remove microorganisms and fine particles from wastewater based on size.
More recent forms of tertiary treatment include advanced oxidation technologies to break up chemical pollutants — specifically organic chemical compounds — in wastewater streams.

Wastewater Treatment
in Cape Town

Currently, the City of Cape Town has 17 wastewater treatment works (sewerage works) and 6 smaller facilities spread across the Cape Peninsula responsible for treating wastewater derived from industry as well as serviced households. These wastewater treatment plants make use of:

Pre-treatment (i.e. removal of very large solid materials)
Primary treatment (i.e. the sedimentation process is used for removal of solids as well as the removal of grease, fats and oils)
Secondary treatment (mainly activated sludge treatment; rotating biological contactors and biofiltration as well as oxidation ponds in rural areas) as well as treatment processes for disinfection (i.e. chlorination, ozonation and UV radiation treatment) prior to discharging the treated effluent into the environment or re-using effluent for industrial use or irrigation.

There is currently no tertiary treatment done at any of the wastewater treatment facilities in Cape Town. This means that persistent chemical and pharmaceutical pollutants are released into the environment via Cape Town’s rivers — and then into the ocean.

A study of treated wastewater was undertaken in 2016 to identify emerging contaminants of concern in reclaimed potable water and assess the level at which they are removed by water reclamation and wastewater treatment plants in Cape Town, and therefore risks for treated wastewater reuse for drinking or other purposes. Chemicals like acetaminophen, bisphenol‑A, triclosan, estradiol and perfluorinated compounds were all found to be insufficiently removed and therefore a concern for both human and biodiversity exposure, because they build up (bioaccumulate) at ever-increasing levels up the food chain.

In addition, the City of Cape Town operates three marine outfalls that take poorly treated sewage directly into the sea. The only treatment this sewage gets is a form of pre-treatment known as maceration (breaking up solids). This means that everything that is flushed down the toilet, or poured into a drain, in large parts of Cape Town, goes into the ocean.

Ocean as a Dumping Ground

The three marine sewage outfalls operated by the City of Cape Town at Greenpoint, Camps Bay and Hout Bay are among 14 deep-sea marine outfalls depositing municipal and industrial effluent into the ocean around South Africa.

Unlike the other waste water treatment plants around the peninsula, the marine outfalls provide for a preliminary treatment facility only. This means that sand and grit is first removed, then the sewage goes through a series of mesh screens, which then sieves out the larger items such as nappies, plastic, rags and sanitary goods. The sewage is then pumped into the ocean via an underwater pipeline about a kilometer or two off shore at a depth ranging from 20–30 meters.

The City of Cape Town states that the pipelines are “designed to withstand wave actions and possible damage from ship anchors, and they have a diffuser at the end of the pipeline that helps to disperse the waste”. Further they are “carefully designed to safely disperse waste deep underwater, far from the shore and are located in areas where ocean currents help to disperse and carry the effluent away from the coast.” The idea is that the enormous volume of the sea helps to dilute the waste to nearly undetectable concentrations, and bacteria and pathogens die off while mixing with the sea water.

However, these claims have been contested by Camps Bay residents since around 2015, as well as scientists, recreational ocean users, marine specialists, and other concerned citizens. At the end of 2022, the Department of Forestry, Fisheries and the Environment (DFFE) issued Coastal Waters Discharge Permits (CWDPs) for the Hout Bay (10 years), Camps Bay (5 years) and the Green Point (5 years) marine sewage outfalls, as is legally required in terms of the National Integrated Coastal Management Act.

The National Sea Rescue Institute (NSRI) and ActionSA have appealed the licenses, which sparked a war of words on social media and fractious engagements between activists, academics and City officials over the assertion that “there is no immediate ecological disaster or major risks to human health forthcoming as a result of the effluent discharged.” This pressure has led the DFFE to re-open the public participation process around the licenses, as that last happened in 2015 and was deemed out of date.

History of Marine Outfalls in Cape Town

Cape Town’s first marine outfall was constructed at Mouille Point as far back as 1895, and four outfalls have since been built in the area. The original outfall was replaced by a 180 metre pipeline in 1927, and most recently upgraded in 1993.

The current main outfall at Green Point that serves the greater central business district from Woodstock to Bantry Bay, is 1 700 m long and daily discharges up to 40 million litres per day at a depth of 28 m below sea level. It was urgently constructed and commissioned in 1993 in order to replace the previous outfall (built in 1985) which had been damaged by winter storms in 1989.

The Camps Bay outfall was commissioned in 1977 in order to replace an inadequate previous outfall. It is licensed to discharge 5 million litres of raw sewage per day into the sea.

The Hout Bay outfall was constructed in 1991 and became operational in 1993 after the completion of the pre-treatment works in 1992. It discharges up to 9.6 million litres of sewage per day.

A fourth marine sewer outfall is located on Robben Island and is managed by the Department of Public Works.

Dr Neil Overy, a historian affiliated to Environmental Humanities South, has published a study of the history of City Council’s decisions about the Green Point outfall in which he argues that:

“The City of Cape Town pumps 40 million litres of untreated sewage into the Atlantic ocean from the Green Point outfall pipeline every day. This results in microbial and chemical pollution of the sea (including persistent organic pollutants), marine organisms and recreational beaches, all of which breaches the City’s constitutional commitment to ‘prevent pollution and ecological degradation’ and in doing so fails to uphold the constitutional right to an environment that is not harmful to ‘health or well-being’.”

This study illustrates how narrow economic interests from the early 1880s to the present day have driven the City’s commitment to the Green Point outfall despite a long history of opposition from citizens and scientists and repeated instances of pollution and ill-health caused by sewage in the ocean. The findings reveal how, rather than being the cost-saving option that the City has consistently claimed it to be, the maintenance of the outfall has cost enormous sums of money. Read more >

City of Cape Town Information on Marine Outfalls

Sensitivity map for Glen Country Club showing marine outfall pipe location (Marine Environmental Impact Assessment — CoCT Desalination Plants)

Green Point Outfall: Alleged Sewage Pollution of Beach: JW Yolland versus City Council, 1929. Photographic evidence for March 1929 Supreme Court Case (Cape Archives)

Cape Town’s first marine outfall was constructed at Mouille Point as far back as 1895, and four outfalls have since been built in the area. The original outfall was replaced by a 180 metre pipeline in 1927, and most recently upgraded in 1993.

City of Cape Town Information on Marine Outfalls

The current main outfall at Green Point that serves the greater central business district from Woodstock to Bantry Bay, is 1 700 m long and daily discharges up to 40 million litres per day at a depth of 28 m below sea level. It was urgently constructed and commissioned in 1993 in order to replace the previous outfall (built in 1985) which had been damaged by winter storms in 1989.

The Camps Bay outfall was commissioned in 1977 in order to replace an inadequate previous outfall. It is licensed to discharge 5 million litres of raw sewage per day into the sea.

Sensitivity map for Glen Country Club showing marine outfall pipe location (Marine Environmental Impact Assessment — CoCT Desalination Plants)

The Hout Bay outfall was constructed in 1991 and became operational in 1993 after the completion of the pre-treatment works in 1992. It discharges up to 9.6 million litres of sewage per day.

A fourth marine sewer outfall is located on Robben Island and is managed by the Department of Public Works.

Dr Neil Overy, a historian affiliated to Environmental Humanities South, has published a study of the history of City Council’s decisions about the Green Point outfall in which he argues that:

“The City of Cape Town pumps 40 million litres of untreated sewage into the Atlantic ocean from the Green Point outfall pipeline every day. This results in microbial and chemical pollution of the sea (including persistent organic pollutants), marine organisms and recreational beaches, all of which breaches the City’s constitutional commitment to ‘prevent pollution and ecological degradation’ and in doing so fails to uphold the constitutional right to an environment that is not harmful to ‘health or well-being’.”

This study illustrates how narrow economic interests from the early 1880s to the present day have driven the City’s commitment to the Green Point outfall despite a long history of opposition from citizens and scientists and repeated instances of pollution and ill-health caused by sewage in the ocean. The findings reveal how, rather than being the cost-saving option that the City has consistently claimed it to be, the maintenance of the outfall has cost enormous sums of money. Read more >

Green Point Outfall: Alleged Sewage Pollution of Beach: JW Yolland versus City Council, 1929. Photographic evidence for March 1929 Supreme Court Case (Cape Archives)

Is Dilution the
Solution to Pollution?

Marine effluent outfalls have been a popular method of sewage disposal for coastal cities for years, defended by the idea that “the solution to pollution is dilution”. The outfalls in Cape Town are designed on the scientific premise and assumptions articulated in 1959, by A M Rawn, who discounted the need for a secondary treatment facility and stated that the “good old ocean does the job for free” (Beder, 1992:62). According to epidemiologist Dr Jo Barnes, in her submission to the Department of Environmental Affairs regarding the license application for the Camps Bay marine outfall:

“There are several reasons that marine outfall disposal proved to be so popular over the centuries. There was an almost unshakeable faith in the ability of dilution/dispersion as a process to purify effluent or at least make it ‘disappear’. The assumption was that if small amounts of heavily contaminated sewage effluent are introduced into the ocean, then the subsequent dispersal into such a large body of water will dilute the pollutants to such a low level that they will be harmless and thus over time their detrimental effect will be removed.”

When these outfalls were commissioned in previous decades, the engineers could not take into account the mind boggling quantity, complexity and toxicity of chemicals that are now readily disposed, both legally and illegally, into these sewerage systems. Dilution is not the only mechanism that operates in the sea, as Jo Barnes explains:

“Various components of the effluent tend to accumulate or agglomerate in the marine environment while some organisms and chemical compounds will eventually bioaccumulate in the food chain. This process is not linear — it accelerates over time and thus its effects become more and more noticeable as the disposal process carries on unrelentingly. Fat particles especially tend to agglomerate and form ‘fat balls’. Disease-causing organisms such as viruses and bacteria tend to cling to the fat particles and can survive for much longer in these fat balls than previously thought. Grease of mineral origin is furthermore resistant to biodegradation and can linger in the environment for much longer than previously thought.”

Although sewage outfalls are common in coastal cities around the world, the CSIR states:

“The world cannot use the marine environment as a waste receptacle in perpetuity and opportunities for improved and economically and environmentally feasible wastewater treatment, and the feasibility of using alternate strategies for disposing of wastewater to the marine environment should be investigated by the City of Cape Town (and other municipalities).”

A City of Cape Town public information pamphlet describes how the three marine outfalls push wastewater through diffusers deep under water far into the sea, located in areas where ocean currents help disperse and carry the effluent away from the coast. However, this has been questioned by a number of researchers and local residents.

Beach management requires more than samples taken every 2 weeks, as has been the practice in Cape Town. Faecal contamination can be cleared in a matter of days, and therefore may not show up in the water quality findings. In the Know Your Coast reports from 2019, 2020 and 2021, water quality figures for Three Anchor Bay and Hout Bay are consistently poor, and Camps Bay trends towards average, though overall, more average to poor. Stormwater drains and other pollution sources like ships and pet waste are blamed, though this argument has been contested. The presence of chemicals bioaccumulating in marine species close to shore indicates levels of sewage higher than such sources alone could be responsible for. Concerned citizens have been calling for Cape Town beach management to follow best practice internationally, and to work on predictive modelling until such time as the marine sewer outfalls are replaced with appropriate treatment facilities.

“Consultants who work in outfall modelling will tell you it’s inadvisable to place outfalls in bays because they are known as retentive zones. Wastewater pumped into a bay never really makes it out; it simply gets retained in that environment. The outfalls in Green Point, Camps Bay and Hout Bay are subject to that concept. The Green Point outfall is on the edge of Table Bay and is in a wind shadow. The summer south-easter, which would blow the plume offshore, doesn’t reach it. And the prevailing winter wind, the north-wester, blows the plume towards the shore.” How we are soiling the sea, The Big Issue

Stormwater

Stormwater is the runoff of water that occurs from urban and rural surfaces when it rains. Cape Town’s stormwater system, which drains the city and prevents waterlogging and flooding, is a network of built infrastructure integrated with natural water bodies such as rivers, wetlands and the ocean.

Cape Town’s stormwater system consists of:

150 000 gullies/intakes;
16 630 kilometres of pipes and culverts;
890 detention ponds;
236 stormwater treatment wetlands;
1 910 kilometres of rivers and streams;
thousands of wetlands, including ‘vleis’ and estuaries;
27 stormwater pump stations;
59 rainfall and flow monitoring stations; and
approximately 200 inland and coastal water quality monitoring stations.

The system is managed by the Transport Directorate’s Stormwater Management Service who have the responsibility of ensuring stormwater is channelled into the environment safely and does not pose public health risks. Their responsibility is to plan stormwater infrastructure, protect rivers and vleis and the ocean (“receiving water bodies”) from pollution, and to plan for disaster situations like floods. Yet the City’s canals, rivers, wetlands and the ocean are also the responsibility of other departments like Water and Sanitation, Solid Waste, Coastal Management and Environmental Health, who all need to work together to ensure Cape Town’s water is clean and healthy. Coordinating all these different departments to protect the rivers, wetlands, vleis and oceans, is clearly a very difficult task.

In an organisational structure that facilitates inter-departmental finger-pointing, who actually takes responsibility for the care of Cape Town’s rivers? They are currently in a shocking state, although civic organisations like Friends of the Liesbeek River, Friends of Zeekoevlei and Rondevlei, Help Up! and Action for Responsible Management of Our Rivers (Armour) have been stepping into the vacuum to care for and clean them.

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You can explore the open waterways around Cape Town on this map on the City’s Open Data Portal.

Pollution in Black River. Photo: Belinda Johnson

Informal Settlements

“Burst sewage pipes, limited water pressure and overfilled chemical toilets leaving a lingering stench in the atmosphere are what come to mind when I think of sanitation in the two informal settlements of Imizamo Yethu and Hangberg. While both these areas have formal housing, a shortage of affordable housing drives the construction of informal dwellings, both in the formal parts of the neighbourhood (as backyard dwellings), or in the informal areas.” Faith Gara

Insufficient sanitation services characterise all informal settlements and some low-income areas in South Africa. Cape Town is no exception, where local frustration around lack of service delivery has boiled over into “poo protests.” In their 2016 study McFarlane and Silver explore how these protests gave rise to new social movements in Cape Town that recognise apartheid spatial planning has not been remediated, resulting in constant indignity of inadequate water and sanitation services. Water is dignity!

Without adequate housing in the city, many householders in low-income areas have built backyard dwellings, resulting in more people living in an area than the sewerage system was planned to serve. Toilet facilities are vastly overused and suffer continual breakdowns and damage. Some of this damage is due to vandalism, but is mostly simply the result of huge pressure on the hardware from overuse. When there are, say, 60 persons to a working toilet, then no hardware can cope with such a burden for long before breaking down. This can lead to sewage spills. When it rains, stormwater picks up the excess sewage, either through run-off from areas of open defecation, or through direct dumping of sewage into drains. This untreated wastewater then contaminates water bodies, affecting biodiversity and nearby communities.

As part of her Master’s research study, Faith Gara documented experiences around water of residents in the Hangberg and Imizamo Yethu neighbourhoods of Hout Bay. Her work contributes to a water-sensitive design for a “Liveable” neighbourhood in Hout Bay, and forms part of the transdisciplinary Liveable Neighbourhoods Project. Sanitation challenges in these two areas stem from ageing infrastructure, insufficient housing and lack of properly installed and planned sewage systems.

In the informal area in Imizamo Yethu, the City provides communal taps and shared toilets – (both flushing and chemical toilets). However, these sanitation facilities are a subject of contestation, as residents demand dignified sanitation services. Some communal flushing toilets do not function properly and have broken doors, and no lighting while the chemical toilets are mostly always overfilled. Shared sanitation facilities are also not safe to use in the dark, especially for women and children, leaving residents to use a bucket to relieve themselves in the night. These buckets are sometimes emptied in bushes or stormwater drains as the toilets are usually occupied in the mornings when residents are preparing for the day. Plastic bags containing sewage are also often disposed of into the solid waste skip (large communal container for rubbish). Thus the solid waste in many under-serviced townships is suffused with sewage.

Areas with high population density and limited services contribute a huge amount of pollutants and effluent from household chemicals, dirty drains, piles of rubbish, bacteria in faecal waste and other contaminants from human waste are often in the streets from the broken down sewage systems. These pollutants are washed into surface water bodies through stormwater runoff. They also seep into the soils, plants and atmosphere and groundwater facilities. Impacts of this toxic mixture, exacerbated by changing weather systems that lead to flooding and fire disasters, remain a huge concern for human health and ecological wellbeing. Studies show that areas like Imizamo Yethu falls within a high-risk health category, and an informal settlement without sanitation effectively recreates apartheid’s segregation practices.

Insufficient sanitation services characterise all informal settlements and some low-income areas in South Africa. Cape Town is no exception, where local frustration around lack of service delivery has boiled over into “poo protests.” In their 2016 study McFarlane and Silver explore how these protests gave rise to new social movements in Cape Town that recognise apartheid spatial planning has not been remediated, resulting in constant indignity of inadequate water and sanitation services. Water is dignity!

Without adequate housing in the city, many householders in low-income areas have built backyard dwellings, resulting in more people living in an area than the sewerage system was planned to serve. Toilet facilities are vastly overused and suffer continual breakdowns and damage. Some of this damage is due to vandalism, but is mostly simply the result of huge pressure on the hardware from overuse. When there are, say, 60 persons to a working toilet, then no hardware can cope with such a burden for long before breaking down. This can lead to sewage spills. When it rains, stormwater picks up the excess sewage, either through run-off from areas of open defecation, or through direct dumping of sewage into drains. This untreated wastewater then contaminates water bodies, affecting biodiversity and nearby communities.

As part of her Master’s research study, Faith Gara documented experiences around water of residents in the Hangberg and Imizamo Yethu neighbourhoods of Hout Bay. Her work contributes to a water-sensitive design for a “Liveable” neighbourhood in Hout Bay, and forms part of the transdisciplinary Liveable Neighbourhoods Project. Sanitation challenges in these two areas stem from ageing infrastructure, insufficient housing and lack of properly installed and planned sewage systems.

“Burst sewage pipes, limited water pressure and overfilled chemical toilets leaving a lingering stench in the atmosphere are what come to mind when I think of sanitation in the two informal settlements of Imizamo Yethu and Hangberg. While both these areas have formal housing, a shortage of affordable housing drives the construction of informal dwellings, both in the formal parts of the neighbourhood (as backyard dwellings), or in the informal areas.” Faith Gara

In the informal area in Imizamo Yethu, the City provides communal taps and shared toilets – (both flushing and chemical toilets). However, these sanitation facilities are a subject of contestation, as residents demand dignified sanitation services. Some communal flushing toilets do not function properly and have broken doors, and no lighting while the chemical toilets are mostly always overfilled. Shared sanitation facilities are also not safe to use in the dark, especially for women and children, leaving residents to use a bucket to relieve themselves in the night. These buckets are sometimes emptied in bushes or stormwater drains as the toilets are usually occupied in the mornings when residents are preparing for the day. Plastic bags containing sewage are also often disposed of into the solid waste skip (large communal container for rubbish). Thus the solid waste in many under-serviced townships is suffused with sewage.

Areas with high population density and limited services contribute a huge amount of pollutants and effluent from household chemicals, dirty drains, piles of rubbish, bacteria in faecal waste and other contaminants from human waste are often in the streets from the broken down sewage systems. These pollutants are washed into surface water bodies through stormwater runoff. They also seep into the soils, plants and atmosphere and groundwater facilities. Impacts of this toxic mixture, exacerbated by changing weather systems that lead to flooding and fire disasters, remain a huge concern for human health and ecological wellbeing. Studies show that areas like Imizamo Yethu falls within a high-risk health category, and an informal settlement without sanitation effectively recreates apartheid’s segregation practices.

A Perfect Storm

Most of Cape Town’s 14 rivers and 10 wetlands are critically polluted with microbial, chemical and other forms of pollution. In a recent article in Ground Up, environmental journalist Steve Kretzmann writes:

“Some of Cape Town’s rivers and canals are so polluted they are essentially open streams of sewage, and although the City of Cape Town is aware of this, the water and waste directorate has vastly underspent its budget for the past two financial years.”

The situation has been attributed mainly to ageing infrastructure, expanding informal settlements, and loadshedding of electricity which affects pumps in wastewater treatment plants. The City of Cape Town often finds itself at odds with citizens over their handling of water pollution, despite infrastructure upgrades being carried out and planned.

The lack of sanitation infrastructure in Joe Slovo and Dunoon informal settlements next door to Milnerton for example, combined with the already struggling Potsdam Waste Water Treatment plant, creates a perfect storm of contamination and associated algal blooms in the Diep River and Milnerton Lagoon. The situation was recently explored by Mycelium Media Colab for the SABC environmental show “50/50” in an overview of ocean pollution around Cape Town.

Zeekoevlei

Fed by the Lotus River, Zeekovlei is a beautiful haven for wildlife and humans, whose reeds and wetlands filter extraordinary levels of pollution flowing into it from the river. Zeekoevlei was awarded Ramsar status in 2015 as a “wetland of importance.”

Although Zeekoevlei is part of the False Bay Nature Reserve, it has experienced sewage contamination for over ten years. A series of spills in August and September 2020 resulted in closures and warnings to stay out of the water, a situation that recurred in July 2021, with the vlei currently closed for water use, though the terrestrial part of the Zeekoevlei has been opened for activities such as bird watching, jogging, walking and cycling.

The first spill appears to have been caused by a fault at Brown’s Farm. The official reason given for the second pollution event was “vandalism to a low-flow stormwater to sewer diversion … used to direct polluted stormwater into waste water treatment plants.” Yet this explanation does not explain the huge quantities of pollutants that entered Zeekoevlei.

Various methods were used to restore acceptable water quality, such as solids removal, use of enzymes, skimming, and removal by excavator, but much damage has been done to the ecosystem. It is easy to pour in a bucket of bioenzymes to kill off the E.coli, but much harder to remove the excess nutrients that enter the vlei, and which are likely to lead to algal blooms in summer.

What will it take for the City of Cape Town, researchers and citizens to engage proactively to clean our precious water that sustains us all?

“No fences and no laws halt flows of rock, water, and life. There is no division of “city” from “nature.” There is no pipe that goes nowhere.” Rock | Water | Life