Bubble Bubble Toil and Trouble by Roxy Davis

We are regularly asked about the brown bubbling sea foam that makes its way to our beaches. It can be a little disconcerting when you suit up and start wading through murky waters not knowing what may float on by. 

One's immediate reaction leans to a burst pipe or waste outlet making its way into the ocean.......and we have certainly seen our fair share of unsavory waters in the Cape lately! 

However, the mystery of the brown sea foam is really no mystery at all. Haven’t you wondered why you only ever see the murky brown water and foamy beach after a big swell or strong winds?

"In basic terms, it's not wastage or anything sinister but rather just microorganisms that normally can't be seen."

Each coastal region is unique and will have different conditions governing the formation of sea foam but in short sea foam forms when a high concentration of dissolved organic matter such as phytoplankton is churned up by wind and larger swells. In basic terms, it's not wastage or anything sinister but rather just microorganisms that normally can't be seen. However, when they are concentrated (by big swells) the chlorophyll in their cells gives the water a discoloured appearance. 

We can't speak for any other brown and murky waters but when it comes to sea foam, we're quite happy to paddle through (with our mouths closed of course) knowing its actually a sign of a healthy and productive ocean ecosystem. It is still always good practice though to rinse off afterwards to help preserve your suit (and to avoid any possible itchiness).

If you do however seriously suspect there may be something foul in the water you can SMS the City of Cape Town on 31473 with your message and contact details or email them on contact.us@capetown.gov.za and they will put you in contact with the correct local Environmental Health Representative. 
 
Author: Roxy Davis
Editor: Roxy Davis
Photography: Graeme Field @ That's Me! Surf Photography

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