“This is a massive screw up,” said Abhijit Singh, who heads the Observer Research Foundation’s (ORF) Maritime Policy Initiative . “Something isn’t adding up. The initial reaction was very tardy and there was an attempt to hush up.”

What follows is the first detailed account of the collision and its aftermath, revealing a series of oversights and operational missteps that put India’s eastern coast at peril .

Port officials have prevaricated on everything from the quantity of oil spilt and the time needed for cleanup, to the long-term effects on the region’s fragile and besieged marine ecology.

A fortnight after the Dawn Kanchipuram spilt an estimated 75 tonnes of bunker oil — a heavy petroleum residue used to start ship engines — port authorities are yet to explain how two enormous tankers, each freighted with inflammable hydrocarbons, could collide three kilometres off the Chennai coastline.

The errors began as soon as the Maple left its berth. At Kamarajar Port, like elsewhere in the world, specialist navigators, called pilots, accompany large ships out to sea.

But according to a police report filed by A.K. Gupta, the port’s Director for Marine Services, the Maple let go of her pilot, V. Karunanidhi, well before his designated disembarkation point as Capt. Sahadevan was confident of navigating the ship by himself.

M.A. Bhaskarachar, Chairman and Managing Director of Kamarajar Port, said Karunanidhi continued to monitor the Maple’s progress and even messaged the Maple at 3:24 am to say: you are going to collide, be careful.

It is unclear if the Maple acknowledged this message. The ship stayed its course and continued to pick up speed until it collided, 20 minutes later, with the Kanchipuram at 3:45 am.

“Every harbour has its own idiosyncrasies. Captains, irrespective of experience, must rely on a pilot – those are the rules.” - Former harbour pilot

Once the collision occurred, the port’s pollution response fell apart.

The authorities claimed only one tonne oil had spilt, and then said 20 tonnes after the Coast Guard issued a separate statement. The final quantity of spilt oil, officials privately admit, could rise to 100 tonnes.

“The port should handle a spill of this size, but couldn’t. We came in because they asked us for help,” said a senior officer in the Coast Guard. “By then much of the damage was done.”

One plausible scenario is that the port panicked, sought to suppress news of the incident, and called the Coast Guard only once they realised the scale of the spill.

So when did port authorities learn of the accident?

“We cannot say anything, investigation is underway,” said A.K. Gupta, Kamarajar’s Director for Marine services. But a press release states the Coast Guard was informed at 6:15 am and spill containment measures began at 7 am, three hours after the incident.

This may seem like a short time, but experts disagree.

“If a tanker is involved, you need to send a team in half an hour,” said Singh, from the ORF, “These are standing operating procedures, it is not a discretionary decision.”

In 2012, the Indian government hired Saab, a Swedish military supplier, to set up a network of radars, radio receivers and cameras — called the National Automatic Identification System (NAIS) — to improve coastal surveillance in the aftermath of the 2008 Mumbai attack.

“The system can track anomalies and send alerts if a ship suddenly veers off course, or if a ship suddenly stops or collides," said an expert who has worked with the system, requesting anonymity to discuss sensitive technology.

“The coastguard has a guy tracking the NAIS at all times,” said a retired Coast Guard official, noting that the NAIS has a centre in Chennai. “In this day and age, no one needs to inform anyone about anything, just look at your damn screen.”