11 February,2017 08:56 AM IST | | Vinod Kumar Menon
Will have short- and long-term effects on marine ecosystems, they claim; micro-organisms have already been affected
The spill at Bharati Nagar beach
The oil surfacing on the sea after the spill off the coast of Tamil Nadu in January will have both short and long-term repercussions on marine ecosystems, say experts from the Integrated Coastal and Marine Area Management (ICMAM) Project Directorate in Chennai.
The oil spill explained graphically
A scientist, talking about the immediate action after the spill on January 28, said, "The first respondent was Indian Coast Guard, which deployed its contingent for cleaning, containment and recovery. Simultaneously, INCOIS, Hyderabad (Ministry of Earth Sciences), came forward for trajectory modelling, and disseminated the information to user agencies."
Spill spread speedily
ICMAM Project Directorate carried out a preliminary assessment survey of the spill on January 29. By 6 am of January 29, the oil had reached Nettukuppam coast, the northernmost point up to which the spill extended, beached in the rocky sea walls at Kasi Koil Kuppam, going up to the beaches north of fishing harbour, Royapurm.
A major portion of the spilled oil mixed with water/sludge was trapped at Bharathi Nagar and RadhaKrishna Nagar Kuppam beach. Further down south, at Washermenpet, floating oil patches in the nearshore water, and tar balls on beaches were observed.
Water and sediment samples were collected to assess the before and after changes in the water quality from Ennore to Thirvanmiyur (as many as 14 locations) between January 29 and February 1.
Micro-organisms affected
Dr MV Ramana Murthy, scientific head and director of ICMAM, said, "The phytoplankton (or microalgae) and zooplanktons (microscopic animals) are at greater risk than the other biotic components of the marine ecosystem due to the proximity to hydrocarbon compounds floating on the sea surface, and their general sensitivity to the toxic components in the hydrocarbons. These planktons play a major role in the marine food chain, and were found to be stressed during this event."
"The hydrocarbon compounds adversely affected phytoplankton populations, their patchy distributions. No mass mortality of fish was reported during the investigation; however, a few incidences of olive ridley turtle mortality were reported," he added.
"Our report has been submitted to the Ministry of Earth Sciences and it will take a few months before the situation comes back to normal. Fishermen have restarted venturing into the sea, and they get their catch from a distance of over 5 km inside," he said.
Here's how it happened
In the early hours of January 28, a tanker, BW Maple, carrying LPG, weighing 58,000 tons, and Dawn Kanchipuram, carrying a chemical, weighing 45,000 tons, met with an accident about two nautical miles (3.7 km) in the waters of Kamaraj (Ennore) Port, north of Chennai harbour.
