How we are soiling the sea

[dc]An aerial photograph of Table Bay, showing a large plume of sewage stretching across the cobalt blue waters in front of Table Mountain, caused mayhem on social media last year. It was posted by marine conservation photographer Jean Tresfon and Capetonians couldn’t believe it.[/dc]

In aerial photograph of Table Bay, showing a large plume of sewage stretching across the cobalt blue waters in front of Table Mountain, caused mayhem on social media last year. It was posted by marine conservation photographer Jean Tresfon and Capetonians couldn’t believe it.

Many still don’t know that about 55 million litres of raw, untreated sewage and greywater is pumped into the ocean off Green Point, Camps Bay and Hout Bay every day via underwater pipes known as outfalls.

“What is going out into the ocean is essentially a mixture of your sewage waste, as well as every chemical you use in the household, for medicinal or for cleaning purposes,” explains Professor Leslie Petrik from the University of the Western Cape’s Chemistry Department.
Her breakthrough study at the Green Point outfall last year found the presence of dangerous toxic compounds in marine organisms.

These three outfalls are operated by the City of Cape Town municipality and are just three among the 14 deep-sea marine outfalls depositing municipal and industrial effluent into the ocean around South Africa.

They may be labelled ‘deep sea’ but they’re not very far from shore. The Green Point outfall is 1,6km off the promenade. It deposits the most sewage of the three, about 40 million litres a day, and serves the greater CBD, from Woodstock to Bantry Bay. The Camps Bay outfall is 1,4km off the popular tourist beach and pumps out about 5,5 million litres of wastewater a day. The Hout Bay outfall is 2,1km from the beach (but far closer to Dungeons, the big wave surf spot) and pumps out about nine million litres of wastewater a day.

Problem areas

The only ‘treatment’ the sewage undergoes, is called preliminary treatment. It entails the effluent being pumped through a grid with metal bars about 1–2cm apart. This removes the larger objects like rags and big plastic items. The rest is sent out into the marine environment.

The City says on its website that while people may “feel uncomfortable about discharging largely untreated wastewater into the sea, it is important to consider that marine outfalls are carefully designed to safely disperse wastewater deep under water, far from the shore”. It adds that they’re also located in areas where ocean currents help disperse and carry the effluent away from the coast.

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.

Kayakers, surfers and swimmers have come forward with evidence of falling ill after using the sea recreationally off the Atlantic seaboard. And E. coli is no longer the biggest threat. When Prof Petrik and her team visited the Green Point site in July last year, they tested for the presence of 12 toxic compounds in brittle starfish, sea urchins and ordinary starfish collected off the seafloor. They were surprised by the results.

Some of the toxic compounds tested for include bisphenol A, which is a potent endocrine disruptor. It can cause birth defects, growth abnormalities and lead to increased feminisation in species. The other compounds tested for are no less problematic and are likely to cause growth deformities, cancers or have transgenerational effects on marine species, says Prof Petrik.

Acetaminophen (another endocrine disruptor found in paracetamol), nitrophenol (which comes from herbicides, pesticides and fungicides) and perfluorinated compounds (found in stain repellants and non-stick coatings) were included in the study.

“We found that all the compounds we were testing for were present in the marine organisms, except for two compounds that didn’t show in the brittle starfish. The compounds were also higher in the marine organisms than in background levels. The compounds were about 10 to 70 times more concentrated in the marine organisms.”

According to Prof Petrik, these compounds are far more dangerous than the actual sewage. “The sewage will still probably decompose over time, but many of these compounds are very persistent and will bioaccumulate within the environment.” When the smaller animals are eaten by bigger ones, the toxic compounds are transferred as they make their way to the top of the food chain and eventually onto our plates.

The permit and an ignored petition

Shortly after Tresfon’s photographs went viral, the City had to reapply for a Coastal Waters Discharge Permit (CWDP) for each outfall. This happened because the mandate for outfalls was handed over from the Department of Water and Sanitation to the Department of Environmental Affairs (DEA). A public participation process was advertised on the City’s website and the public and stakeholders had a window to comment on the outfalls, closing on 10 July 2015. The comments would be submitted as part of the application.

The City says they received 507 comments, and 1 155 emails as part of an Afriforum petition. Cape Town resident Alistair Scott also sent in a petition with 2 051 signatures, which the City didn’t include in their initial count. “The participation process and the follow-up process is lacking in a big way,” says Scott.

Alderman Ernest Sonnenberg, the Mayoral Committee Member for Utility Services, has now confirmed the City did receive the online petition but they are currently seeking advice from the DEA as to “how this should be considered and weighted”.

“There are concerns surrounding the methodology (signatories included a number of people who are not South African citizens), and whether the way the issue was presented to signatories created unfair prejudice,” says Sonnenberg. The signatories were for the most part, South African. (The petition can be viewed at causes.com/actions/1779348.)

The application process should not take more than eight months, says the National Guideline on Public Participation Requirements for the Issuing of a Coastal Waters Discharge Permit. But it’s been 16 months – and counting. During this time about 20 billion litres of untreated wastewater has been discharged into the ocean.

“The only thing the City has done about the outfalls in the last year is to appoint the CSIR (Council for Scientific and Industrial Research) to do a study. The City promises action and then waits for public interest to die down,” says Tresfon.

A scientific report

Sonnenberg has confirmed the City’s application is in limbo, but says that’s because they are doing tests at the outfall. “The DEA is awaiting these test results to inform the conditions that they will impose in the Coastal Waters Discharge Permits.”

The application for these permits will be resolved as soon as the final report from the CSIR is handed to the DEA, he says, which is envisaged to be in November or December this year. “Once the regulator has studied the report, they will issue the discharge permit,” he adds.

A CSIR scientist has confirmed he is busy with the research. Brent Newman, principal researcher and environmental chemist for the organisation in Durban, is working on the study, commissioned in September last year.

He has confirmed they’re testing for bacteria on the surface of the outfalls and for chemicals around the outfalls. Then every two months they test the toxicity of the wastewater before it is pumped out through the outfall pipe. This helps them to analyse the dose of certain chemicals and how much it would need to be diluted by seawater in order to meet general standards.

They are also taking sediment samples at the outfall discharge area and near the shore and testing these for various chemicals. Crayfish and mussels will also be tested for chemicals in the three areas.

“We test for about 200 chemicals,” says Newman. However, the CSIR’s list of chemicals does not include the hazardous toxic compounds that Prof Petrik tested for. “We have to put a limit on the list we look at,” explains Newman. “There are an estimated 10 000 chemicals that are in regular use. Where do you start or stop? Some chemicals are quite expensive to test for, and so one cannot test for all possible chemicals. We thus use certain chemicals as markers, or indicators, and often also focus on chemicals that have associated water quality guidelines. A rather small number of chemicals, in fact, have associated guidelines.”

Newman and his team are testing mussels directly inshore from the outfalls and some samples are taken much further away. “We are testing mussels in Kommetjie for the Hout Bay outfall,” says Newman. “So we look at what we’d find at an impacted site and further away.” The CSIR report is due to be delivered to the City this month (November).

The DEA says it will submit the result of the permit applications by March 2017, so it can be assessed in the current financial year.

Will the permits be approved?

Newman says the permits will probably be approved. “The concern isn’t really whether it will be approved or not. It’s the conditions included in the permit that are important,” explains Newman. “I can’t speak for the DEA but they may make specific conditions for the Cape Town outfalls.”

“Of course the permits will be approved,” says Tresfon. “Where else are they going to put the sewage? And the likelihood of some sort of appeal against the decision is high.

“The outfalls contravene several existing pieces of legislation. The Marine Living Resources Act, for example, says no dumping is allowed in a marine protected area. Two of the outfalls, Camps Bay and Hout Bay, fall squarely within the Table Mountain Marine Protected Area and the Green Point outfall is about 200 metres from that boundary.”

The Table Mountain Marine Protected Area runs from Mouille Point, out to sea for three kilometres and around the peninsula, past Cape Point, to Muizenberg.

Megan Laird, a marine consultant at Anchor Environmental Consultants who specialises in effluent modelling and toxicity testing, says that sensitive environments, such as marine protected areas, should not be in close proximity to effluent outfalls.

“They are clearly dumping against the law,” says Tresfon. “I cannot understand why a city that is so progressive in so many other aspects cannot seem to understand the damage that is being done to the marine environment.”

R4 billion spend on sewage plants

Budget and space are the major factors holding the City back from implementing a green wastewater solution for these outfalls. It has 27 wastewater treatment plants and several need immediate increases in treatment capacity.

Sonnenberg says the cost of renovating four of these plants will be “in the region of R4 billion” and will have to be completed within the next five years. “The outfalls are licensed and in terms of dispersing pathogens such as E.coli into the ocean, the risk to human health is insignificant, and environmental impacts are limited to the immediate area surrounding the outfall,” he says. “As long as we are licensed to do so and testing reveals negligible or manageable environmental impact, there is little to motivate the expenditure when balanced against other development needs in the city.”

In 20 years the population of Cape Town will likely have risen exponentially, even doubled, says Tresfon. “We will go from pumping 50 million litres of sewage every day to 200 million litres because the City doesn’t have an alternative and is not investigating any.” What does Tresfon think we should do? “We should start building alternatives right now.”