THE COUNCIL has reassured residents concerned about a layer of brown foam in the sea.

A concerned member of the public photographed what they believed to be sewage near Basin Road South in Southwick on Wednesday, May 18.

The local resident was walking along the beach when they came spotted the brown foam.

“The amount of sewage being dumped into the sea was incredible,” he said.

“It was very close to the shore. Unfortunately, the pictures don’t show how brown it was.”

However, Brighton and Hove City Council have dispelled the concerns, stating the brown foam is actually marine algae, which is often mistaken for sewage.

“This is marine algae in a stage of rapid growth. It is composed of microscopic plant and animal plankton, not raw sewage,” a council spokesman said. “This is a natural process.

“After the spring equinox, when daylight hours and sunlight increase, the plant (and animal) plankton in the water column respond.

“The plant plankton photosynthesise and proliferate, the animal plankton responds in turn as the plant plankton is a food source.

“Eventually, the algae bloom dies off once the oxygen and nutrient levels in the water have been depleted.

“The various colours seen relate to the algae in various stages of growth. If there is an unpleasant smell, it is due to the algae having died and entered the stage of decomposition - think rotting vegetables.

“If the sunny conditions combine with southerly winds, the algae is ‘whipped up’ onto the surface and blown onto the coastline. This is what is seen and is sometimes mistaken for sewage.”

Last month, hundreds of people took part in a march in Worthing in protest against Southern Water dumping polluted water into the sea.

Last year, beaches across the south were closed after sewage spills, while last month Brighton and Hove Green Party councillors and activists called on Southern Water to stop releasing sewage into the rivers and the sea.

Between 2010 and 2015, the company dumped untreated sewage on more than 10,000 occasions, with 78 per cent of these being illegal.

The company was fined £90 million in July for illegally discharging 21 billion litres of raw sewage.