City of Cape Town rejects sewage claims, says data tells a different story

The City of Cape Town has issued a strong response to claims that sewage pollution is damaging large parts of its coastline, arguing that publicly available data does not support allegations of widespread or persistent contamination.

The response comes after an interview with Helderberg resident and water quality activist Jamii Hamlin, who described what he said were ongoing sewage problems affecting coastal water quality. Speaking in a right of reply, the City’s Manager of Coastal Management, Gregg Oelofse, said the picture painted was inaccurate and deeply frustrating for officials working to monitor and protect the coastline.

Sewage incidents acknowledged, but not constant

Oelofse acknowledged that sewage spills do occur, particularly linked to known problem infrastructure such as the Trappies sewer line in the Helderberg area. However, he stressed that isolated incidents do not automatically mean water quality is poor or unsafe.

He said the city has intensified monitoring along the Strand coastline, including the main surfing and swimming areas, with daily testing from Monday to Friday for the past 18 months – a frequency he described as exceptional by global standards.

According to the City, the last poor water quality result in the Strand area was recorded on 6 October, following a significant rainfall event the previous day. Since then, results through the peak summer season have consistently shown good water quality.

Rainfall remains a key factor

Oelofse emphasised that rainfall has a well-documented impact on coastal water quality in urban environments worldwide, including in Cape Town. He said this relationship has been communicated openly by the city and is reflected in its reporting.

“When it hasn’t rained, the hard data shows the water quality is really very good,” he said, adding that claims of a coastline ‘being destroyed by sewage’ ignore both context and evidence.

Extensive monitoring and independent testing

The city says it runs one of the most comprehensive municipal coastal water quality monitoring programmes globally, covering roughly 300 kilometres of coastline. Dedicated teams collect samples weekly, which are analysed by an independent, accredited private laboratory.

Oelofse rejected any suggestion of bias, saying neither he nor his team are involved in collecting or transporting samples. In addition, Blue Flag beaches are tested separately by different laboratories, providing further oversight.

All results, he said, are published on a public coastal water quality dashboard, presented in line with South African National Water Quality Guidelines, including seasonal and long-term trends.

Ecosystem ‘far from collapse’

Responding to claims of broader environmental degradation, Oelofse pointed to scientific studies and monitoring within marineprotected areas, including long-running fish tagging programmes and state-of-knowledge reports compiled by marine scientists.

He said these show high biodiversity and healthy ecosystems, with pressures mainly linked to illegal harvesting rather than pollution. He cited examples such as increased fish activity and large numbers of humpback whales feeding along the Atlantic seaboard as evidence of a productive marine environment.

Odours are often mistaken for spills

Addressing concerns about persistent sewage smells near Strand’s golf course, Oelofse explained these originate from a major sewage pump station, not from sewage flowing into the sea. Pump stations, he said, are a necessary part of gravity-fed sewer systems and can produce noticeable odours.

Call for informed public debate

While acknowledging that pollution exists in any large city of more than four million people, Oelofse cautioned against equating visible waste or isolated incidents with ecological collapse.

He urged residents to consult the City’s publicly available data and reports before drawing conclusions, saying informed scrutiny is welcome, but claims should be backed by evidence.

“All of the information is there,” he said. “We want people to look at the data for themselves and understand both what the real challenges are – and what they are not.”

For more information, listen to Oelofse using the audio player below: