Residents on the Patinambakkam beach near Marina in Chennai spent a restless and anxious night on Sunday as high speed winds and rain tore through the area. It was after midnight, says 36-year-old Muthumani, when the gust subsided that she finally fell asleep. But much to her angst, she woke up to another peculiar sight.
At close to 4am, on hearing her neighbours gather outside, she rushed to check if the rains had left behind massive damage.
"I barely took two steps outside my house, and there it was, white foam covering the beach and coming up to my waist," she tells TNM. "We have seen this foam form every monsoon but for the first time it has come all the way up to our houses, which is atleast 100 metres away. We got really scared because we don't know how this will affect the health of our children," she adds.
The fluffy white foam spread like a thick carpet across 1 km of this beach, from the lighthouse in Marina to the Adyar estuary further down, on Monday.
Waves of this toxic foam rolled on to the shore with the winds carrying the suds on to the sand. At 5 pm on Monday, little boys and girls from the fisher community were seen running across the foamy beach, scooping up the white froth and throwing them in to the air.
This is the fourth consecutive day that they have been playing with the foam, the children say, unmindful of the fact that the white fluff covering their feet is a toxic byproduct of municipal and industrial waste.
“I am not yet sure in what ways it can harm us. When I stand inside the foam for a long time, my legs feel itchy and weird. But the kids are throwing caution into the air and playing with it,” says Surendran, a fisherman from Pattinambakkam who says that the beach frothing has affected fishing and normal life in the locality.
Due to the excessive foam formation this year, Surendran says that several fisherfolk have desisted venturing into the sea for their daily catch, suffering losses of about Rs 500 every day.
“This time, the foam was much more than what we see every year. It came near our waists, reached our doorsteps and covered our boats and nets. In some houses, it entered the bathrooms and bedrooms. Apart from this, the water hyacinth that has entered the ocean from estuary, due to the rains, also poses a problem. We can’t fish as these plants spoil our nets,” Surendran adds. The fisherfolk with Surendran also added that over the years, they have noted that their nets also get spoilt when they come in contact with the froth.
A yearly monsoon phenomenon, foam formation in Chennai’s beaches have been pegged to the inflow of untreated or partially treated sewage water draining into the ocean.
During the rains, the storm water enters the sewage network leading to overflow in the Sewage Treatment Plants (STPs). The overflowing STPs release untreated or partially treated sewage water containing non-biodegradable and detergent-like effluents. These effluents tend to foam up when the water is agitated, according to experts.
“When there is sudden flow in a waterbody with many blockages, there are plenty of places of turbulence which increases the agitation and creates the conditions for frothing,” says Pooja Kumar, a researcher with the Coastal Resource Centre.
Two of Chennai’s rivers - Adyar and Cooum - which carry most of the untreated sewage from the city, drain into the Marina and Besant Nagar coasts, resulting in heavy foaming in these areas, Saravanan, a coordinator with the Coastal Resource Center, points out, “When it rains, this untreated sewage water collides with the high density salt water in the ocean, leading to the agitated water frothing up.”
Loss of marine life
While the foam itself does not pose a threat to the marine life, the excess effluent filled water draining into the ocean definitely impacts marine health, Saravanan adds.
He adds that over the years, several dead fish have been found floating near the mouth of the Adyar river where it meets the sea, especially during the monsoons.
“The industrial effluents, heavy metals, plastics and other waste flowing into the ocean kills the oxygen levels in the water. The fish die fast in these anaerobic conditions. Moreover, these toxins also settle on the ocean bed, affecting the tiny marine life there. The plastic being washed into the ocean is consumed by the big fish, which also die as a consequence. So the foam as such is not dangerous. The real killers are what causes the foam,” Saravanan adds.
Despite being accustomed to watching their beach froth up every monsoon, residents observe that over the last few years the foaming has increased tremendously - a possible consequence of excessive pollution in these water bodies.
“It was like a white wall near our house this morning. Only when it started raining again did the foam melt away,” Muthumani recounts.