What’s the stain on Camps Bay Beach?

Mark Jackson, Tamboerskloof

Open letter to Councillor Nicola Jowell, Ward 54

Dear Councillor,

On March 16, a video was sent to me showing a roughly 100 metre large brown stain across Camps Bay Beach.

The videographer initially thought it was oil, as it was a greasy sludge. The City quickly responded and claimed it was harmless “tannins” from an overflow incident at our water treatment plant, and “not hazardous”.

I sent a sample for testing, just to be sure. The results are not yet in. (It will take several weeks, as I took it to an academic lab, not a commercial one.)

On Thursday March 30, I photographed another incident of this pollution, and wrote to you about it, requesting you to please investigate. I never received a reply or acknowledgement from you of that email.

Now on April 3, we've had yet another incident of this ugly brown sludge on the beach, presumably again from the treatment works.

I recorded a video of it, available to all on Facebook.com/BayofSewage

What is it? Previously the City claimed it to be a by-product of “flocculation”, a process to remove tannins and other contaminants during water treatment. But the City hasn’t told us what chemical agent they’re using for this process. The most common one for flocculation is “alum”, or “aluminium sulphate”, a metal salt.

A quick Google search shows this is indeed hazardous, causing skin and lung irritation in humans, and death to fishes. I'’ sure you’ll agree, this is not something we want on any beach, let alone our premier tourist attraction site! Other flocculation agents like magnesium sulphate are hardly better, especially once they've accumulated toxins from water.

I've a sample for you to take to our City labs. (I think we both reside in the City Bowl, and I can bring it you? (My contact details are below).

At the very least, this sludge is unacceptable visual and physical pollution, and officials need to be held to serious account over that. So regardless of the lab result, will you please stand up for your constituency, and for the environment, against potentially errant officials over these incidents, so they never happen again? The public and our tourists will thank you.

But if this pollution indeed proves to be much worse than that, i.e. contains hazardous material, then surely a case will need to be laid with the Green Scorpions against our municipal manager? We the public demand no less.

• The Atlantic Sun reported the first incident (Sediment overflow on Blue Flag beach ‘embarrassing’ March 23).

Councillor Nicola Jowell responded to Mr Jackson directly and via the Atlantic Sun:

The Water Works has confirmed that there is a blockage in the stormwater outlet which carries sediment discharge down from the bulk water works up on Kloof Nek. The Water Works will discharge the sediment created in the water treatment process. This sediment is created through the removal of the tannins in the mountain water which is done through a flocculation process. This is a standard practice. This sediment is removed and then released from the water works.

What has happened as it did in a similar manner in 2019 is that there is a blockage in the stormwater pipe that cause the outflow to then find an alternative route which it has done into another stormwater channel and unfortunately out onto the beach. The stormwater department is currently working on clearing the blockage to prevent this. They have found a section of the channel which is blocked by rocks and debris which they are currently clearing and this should resolve the issue. Once cleared the Water Works will do a test of the line with water first.