A reader writes in to draw attention to the appearance of scum floating off Costa Tropical beaches and asks if anybody knows where it is from.
Gazette readers
Are any of the Ayuntamientos along the Costa Tropical aware of the continuous layers of scum floating along on the ebbing tides, along most beaches on the Costa Tropical?
I first noticed this when it was a small problem some years ago, but now the problem has grown in size and increasing regularity. It is now to be found ebbing onto the beaches in Salobrena, La Caleta and Tesorillo every day and I shudder to think what it is composed of.
I know some time ago it was floated (no pun intended) that it was a discharge from a sewage pipe near Nerja and that the problem would disappear when the sewage pumping station on the outside of Nerja was completed. Another suggestion was that it was a discharge from a factory processing hazel nuts.
Whatever it is, it is extremely off putting visually, if not also a health hazard. Do any of your readers know definitively what this is?
John
Toby: yes, of course, send me a photo to info@theseasidegazette.com and I will add it to the Reader’s Letter.
It appears to me that what Paul and John are describing are two different things entirely.
What I photographed floating past my house this morning was far from minor surf scum!!…positively disgusting and full of content.
I have no idea from whence it comes but for sure it is not natural and has been dumped somewhere along the coast..this is also a very common occurrence as well.
ps. Ed..is it possible to attach photo?
Ok Paul. I will take your article with a mouthful of salt water and hopefully nothing else. I do swim like a dog when I see dodgy looking stuff. Head up high. For once . Mouth shut. !!
Paul: Very informative – thank you 😉
This is brown foam which is seen on our beaches from time to time. It is called surf foam or surf scum. It can be easily mistaken for pollution, but it isn’t. It is a collection of millions of microscopic algae (bloom) and is a natural phenomenon. They need sunlight to grow and attach to the bubbles in the surf causing foaming.
How do I know it’s not pollution?
Is there a pipe nearby or odour associated with it? Sewage pollution is normally grey in colour not brown and may contain visible signs of sewage related waste.
Why does it occur?
Surf algae (microscopic plants) are always present in the water and the dissolved organic matter that they contain can produce these foams in response to agitation of the seawater along the shore particularly during windy weather and in exposed locations.
When does it occur?
It occurs when sea temperatures start to rise (usually May) and there are strong on-shore winds. They tend to break up rapidly with tides and changes in weather. Such occurrences around the coast in recent weeks, is a response to the fine weather and strong wind events recently.
Where does it occur?
Anywhere along the coast and can be brought into harbours with the tide. It varies in size at locations along the coast depending on the influence of freshwater sources (rivers) and terrestrial environments (rocks) where the foam multiplies in the breaking waves.
Is it harmful?
Most sea foam is not harmful to humans and is often an indication of a productive ocean ecosystem. This brown foam is not toxic.