Here are the latest developments in the story:
Along beaches including Marina, volunteers are seen lifting oil mixed with sand with their hands, without using any protective gear, and collecting them in bags. "We are happy doing this for others. It smells bad and sticks to our hand," said Amavasai, a worker.
They have no choice. A much-hyped suction machine didn't work as it ended up pulling out more water than sludge.
"We've tried all kinds of technology and found that manual clearing is the only possibility. We've brought in more people," said MA Bhaskarachar, the chairman of Chennai's Kamarajar Port where the ships collided.
Coast Guard helicopters are conducting regular sorties to monitor what they identified as "stagnated thick oil slick" in the area after a ship leaving after emptying Liquefied Petroleum Gas, rammed another ship loaded with petroleum oil lubricant.
Environmentalists are worried about animals like turtles dying because of the oil spill. Four turtles were found dead.
"The spill will affect oxygen supply to aquatic species. More species will die. But we are not able to assess the loss as we don't have a base line," said Emily Titus, an environmentalist. Fishermen have also suffered a dip in business because of rumours of dead fish.
Shakila says she has fish worth Rs 30,000 but no customers. "I've not sold fish even worth Rs 2,000. No one has come to buy fish in the last three days," she said.
Coast Guard ship Varada joined the clean-up ops today along with a helicopter fitted with pollution control equipment.
Besides the coast guard, firemen, port officials, those from Highways and Chennai Metro Water are also helping in the clean-up.
Experts from the Anna university are using an unmanned vehicle to map the spill. K Senthil Kumar, Director, Centre for Aerospace Research, says: "Through the analysis we could locate the spill areas and decide on effective measures".