In early June, Cape Town MMC for water & sanitation Zahid Badroodien stated that “plans are in place” to replace the city’s three marine outfalls (located in Green Point, Camps Bay and Hout Bay) with new wastewater treatment plants.
On the face of it this is a welcome, if long overdue, announcement because these outfalls collectively dump about 40-million litres of untreated sewage into the sea around Cape Town every day.
However, what Badroodien failed to mention is that this plan is just one of several the city is considering, one of which is to simply extend the outfall pipes further into the sea without providing any wastewater treatment. These plans appear in a January 2024 presentation to Cape Town’s mayoral committee by an engineering firm tasked with exploring sewage disposal and treatment options.
According to the presentation, two medium-term options exist. The first is to locate treatment close to the outfalls themselves at an estimated cost of R2.2bn-R3.4bn depending on the extent of sewage treatment.
The second is to extend the outfalls, which will cost R2bn-R3.2bn — depending on how they are secured and the chosen length of the Greenpoint outfall. This option proposes that the Greenpoint outfall be extended by up to 15.3km, Camps Bay by 11.6km, and Hout Bay by 10km.
There are two long-term options. The first upgrades the on-site treatment facilities at the outfalls, assuming they get constructed in the medium term, at a cost of R2bn-R3bn. The second option proposes pumping the untreated sewage to upgraded existing treatment facilities and would cost R6bn-R8bn.
Given that it is the cheapest option, and considering the sunk costs already spent on the outfalls, there is clearly a real danger that they will simply be extended. This is especially so because the same presentation notes that R100m needs to be spent now on repairs and replacement parts to keep the outfalls functioning before any future plans are implemented. In fact, Badroodien recently stated that R140m was actually needed “to ensure the ongoing safe operation of the marine outfalls”.
History shows us that dumping untreated sewage into the sea via marine outfalls is a bad idea — economically, scientifically and socially
History shows us that dumping untreated sewage into the sea via marine outfalls is a bad idea — economically, scientifically and socially. When the first sewage outfall at Green Point was proposed by the city in the 1890s, a Cape Argus editorial stated that “we should prefer to feel that the sewage was conveyed to land”, noting that “the sentiment ... against the further pollution of the bay is so strong”. The city’s mayor at the time described the idea of dumping sewage in the sea as a “suicidal policy” that would “pollute the bay and poison the people”. Despite this sentiment the city went ahead and completed a 182m Green Point outfall in 1905.
Seven years later Green Point residents complained of sewage regularly appearing on rocks and beaches around the outfall. The city’s then sanitary superintendent described the outfall in 1912 as “obnoxious”. Nothing was done until typhoid outbreaks became so common in Mouille Point and Sea Point throughout the 1920s that the city’s then medical officer of health stated in 1927 that the city should stop discharging sewage into the sea or treat it before doing so.
Unwilling to pay for treatment facilities because “capital costs and annual working expenses would be too high”, the city opted to extend the length of the outfall pipe, which reached 640m into the sea in 1931. However, from 1956 onwards sewage was again found on rocks and beaches around the outfall, and by 1962 the city’s then chief engineer concluded that the outfall should be extended again.
Nothing happened, prompting the new chief engineer to report in 1967 that “sewage blooms” regularly appeared along the coastline near the outfall. A 1970 report recommended extending the outfall to 1.8km. Again, nothing happened until 1983, when the city commissioned engineers, much as it has recently, to explore disposal options.
Rejecting proposals to treat the sewage inland because it was “uneconomical”, or to treat it on-site at Green Point for fear of upsetting golfers, the city agreed, yet again, to extend the outfall. It was duly extended to 2.7km by 1986. The city engineer at the time stated that the new marine outfall would provide “a nuisance-free utility for at least 50 years”.
Less than four years later sewage was again appearing on rocks and beaches, leading to the closure of the entire shoreline between Sea Point and Granger Bay. Investigations revealed that the outfall pipeline had been severed 280m from the shore by a storm. Another Cape Argus editorial remarked that “the city council’s befouled chickens have come home to roost. In this day and age it should simply not be pumping raw sewage into the sea.”
The city responded to this crisis by commissioning yet more research, providing four times as much funding to engineers researching sea disposal as those researching treatment. In 1990, repairing and extending the outfall was estimated to cost R30m, as opposed to R68m for sewage treatment. Citing costs, the city predictably opted for the marine outfall.
A Cape Times editorial pithily asked: “Will the council ever learn? ... Persisting in the belief that the sea is the ‘cheapest’ alternative for the disposal of sewage is a short-sighted economy.”
As the city decides what to do about the menace caused by marine outfalls, it is worth recalling philosopher George Santayana’s observation that “those who cannot remember the past are condemned to repeat it”. Current city authorities must not repeat the mistakes of their predecessors and myopically opt for the cheapest option, over the only option — comprehensive sewage treatment — that meets the city’s constitutional commitment to a clean and healthy environment.
This is especially so given how much more we now know about the significant dangers posed to human, animal and ocean health that come from dumping untreated sewage into the sea.
The archival research for this piece was funded by SANOCEAN, a bilateral research programme financed by the Research Council of Norway and National Research Foundation in SA.
• Dr Overy, a freelance researcher, writer and photographer, is a research associate in Environmental Humanities South at the University of Cape Town.
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