Marine Environment: Tarballs Dot India’s West Coast Annually
Tar balls on Juhu Beach, Mumbai. Tar balls are mainly remnants of oil spills but can also be produced when oil slowly escapes from earth's surface above petroleum reservoirs (Photo by Shaunak Modi)
Right after the monsoon spell, the coastlines of India’s western states, from Maharashtra, Gujarat, and Goa to Karnataka, are lined with dark, sticky balls. These are tarballs, a “seasonal phenomena” surfacing on the west coast of India every year between April and August and cause worry to conservationists and researchers. Tarballs affect marine life and flag concerns about oil spills from an offshore oil rig along the Maharashtra-Gujarat coast in the Arabian Sea.
These weathered oil blobs are often remnants of oil spills but can also be produced from natural seeps, places where oil slowly escapes from the earth’s surface above some petroleum reservoirs.
Unpacking the chemical characteristics and fingerprints of tarballs, researchers at India’s National Institute of Oceanography (NIO) documented the sources of the 2010/11 tarballs that appeared in Goa to be from oil tanker wash, while the probable source for the tarballs on Gujarat’s coasts in 2012 was the crude oil spill from the Bombay High (BH) offshore oil rig.
“We initiated the study on tarballs at NIO way back in 2010. We started working on tarballs when there was huge tarball pollution along the Goa coast. And so far, based on our studies, majorly we have found only two sources. One is the oil spills that occur due to ships or shipping operations, and the second main reason is the oil spills that occur in the vicinity of the oil fields,” Suneel Vasimalla, senior scientist from NIO, told Mongabay-India, adding that tar balls are considered “marine pollutants.”
In a 2019 paper, Vasimalla and co-authors confirmed that tarballs collected in May 2017 along Goa’s coast matched oil fingerprints from an offshore oil rig and oil spills along the west coast were attributed to illegal ship discharges into the eastern part of the Arabian Sea.
The authors called for routine and periodic monitoring of oil spills along India’s west coast to protect the marine environment from oil pollution. Vasimalla adds that NIO, in collaboration with Indian agencies, will devise standard operating procedures to handle oil spills from every source.
Shaunak Modi, director of the Mumbai-based Coastal Conservation Foundation, has been running a Twitter account to document these sightings since April this year. “The first lot of tarballs get washed ashore in April, after which there’s a break. Then by mid-June, they start washing ashore again, and you have batches of them coming in every few days and weeks, all the way till August.”
He clarified that this was only a rough timeline. “It’s different if you have cyclones or if the monsoon extends and if it’s late and continues till September-October. In such instances, tarballs do tend to wash ashore even at a later date.”
Modi has been avidly observing these tarballs for over a decade. However, he started actively photographing and documenting them since 2017. “Over time, I started seeing larger tarballs. The largest one I sighted was roughly the size of a basketball sometime in 2018,” he exclaimed, adding that it seemed unnatural. “This cannot be natural, nor can it be healthy for the ecosystem.”
Modi said the city’s civic body organised clean-up activities without any compliance with the standard operating procedures (SOP). “What the Brihanmumbai Municipal Corporation does is it gives contracts to agencies to clean up tarballs. However, these workers are not given any protective gear; these tarballs are treated like the garbage that washes ashore yearly. Tarballs should be treated as a disaster,” he said.
Goa’s Beaches Reveal A Similar Story
A volunteer from Goa’s forest department, who was involved in a tarball clean-up drive along Morjim beach, told Mongabay-India, on the condition of anonymity, that 2021-22 witnessed huge tarballs along almost all beaches, including Morjim, Vagator, Anjuna and Arambol beaches.
He said the forest department had collaborated with the local community to clear the tarballs. “Shack owners and residents had joined to help us manually clean it up. The activity took us two days, but then the high tide came in, and the sea pulled the tarballs back again.”
According to Antonio Mascarenhas, a retired geologist from the NIO, beaches have witnessed a gradual compounding of the issue.
Mascarenhas said though he has never academically studied tarballs, he has seen the problem for over two decades. He recounts his experiences based on interactions with local communities, fishermen and site visits. “Generally, the phenomenon is very pronounced at the beginning of the monsoon.”
Mascarenhas says this year, 2022, was different. “Tarballs were witnessed on Benaulim beach as late as September 17. This is a highly strange phenomenon as tarballs are generally seen in large quantities at the beginning of June. This is due to a direct hit from the ocean waves in June and August.”
Ocean-Atmosphere Patterns
To better understand the connection between the southwest monsoon and the formation of tarballs, Mongabay-India spoke with Akshay Deoras, a research scientist at the Department of Meteorology at the University of Reading.
Explaining the monsoon’s connection with tarballs, he said, “From the southern hemisphere, winds blowing from the Australian coast cross the equator and start hitting the mainland of India around mid-May or June. Since these changes in the wind direction are happening in the atmosphere, including its lowermost part near the Earth’s surface, sea waves also get influenced. This is why during the southwest monsoon season, from June to September, these winds slam India’s west coast. Waves and ocean currents near the surface move towards the west coast, and lead to accumulations like the tarballs being washed ashore along beaches.”
Oil Spills From Ships
According to a report by the Ministry of Shipping, around 95% of India’s trading by volume and 70% by value is through maritime transport.
Addressing the challenges with tarballs is particularly relevant considering India is also a signatory to the MARPOL Convention – International Convention for the Prevention of Pollution from Ships – which covers the prevention of pollution of the marine environment by ships from operational or accidental causes. The MARPOL Convention was adopted on November 2, 1973, by the International Maritime Organisation (IMO).
In an academic paper, Sairam Bhat, a professor of law, stated, “These measures taken by IMO or the provision of the convention such as MARPOL might seem sufficient, but they are not, as the IMO has not shown a willingness to establish requirements based on the best technologies and fuels.”
“IMO’s regulations are mostly codified forms of existing best practices in the industry. Often, the limits and standards that IMO prescribes do not reflect what could have been achieved had better options in terms of technological improvement or the nature of fuel been considered. Thus, in my view, the targets set for the reduction of pollution may not be adequate and could be achieved even in the absence of adequate technological changes,” Bhat, who is also the Coordinator for the Centre for Environmental Law, Education, Research and Advocacy (CEERA) at the Bengaluru-based National Law School of India University (NLSIU), told Mongabay-India.
Bhat stated, in the paper, that matters such as maritime shipping and navigation fall within the ambit of Union List, which means that the union government is directly responsible for handling these issues. “Additionally, under the Territorial Waters, Continental Self, Exclusive Economic Zone and Other Maritime Zones Act, 1976, the power to control and regulate marine pollution falls within the central government’s jurisdiction. The legal obligation to preserve and protect the marine environment is vested in several authorities, including the central government. Pollution Control Boards and municipal authorities do have the power to be called upon for rendering assistance or provision of any specific facilities.”
Bhat’s paper also refers to a previous case – Samir Mehta v. Union of India and others, O.A. No.24 of 2011 – decided in August 2016 by the National Green Tribunal (NGT).
To summarise the facts of the case, in 2011, around 20 nautical miles from the coast of south Mumbai, a ship with over 60,000 tonnes of coal and about 300 tonnes of fuel oil sank and led to a severe spill, resulting in tarballs collecting along the beaches. Environmentalist Samir Mehta filed a petition in the NGT seeking respite on the environmental damage. In 2016, the NGT directed the polluter to pay Rs. five crores (Rs. 50 million) as environmental compensation to the Ministry of Shipping.
As to who can be held responsible for these spills from ships, Bhat said, “For ships causing oil spills, provisions for civil liability laid down under Merchant Shipping Act, 1958 may be invoked. The owner of a ship causing an oil spill can be held liable from the first instance of occurrence if it is a series of events that has led to the oil spill.”
Regarding the environmental consequences of biodiversity, Modi said that marine animals often ingest the oil. Referring to an encounter with a dead sea turtle that researchers found, Modi said they had found oil inside the turtle’s body. “Unfortunately, the turtle didn’t make it. We found that there was oil in the throat and the digestive system. I’m not saying the turtle was covered in oil, but there were visible amounts of oil inside the body.”
On policies meant to protect biodiversity, Bhat said, “There are legal provisions to ensure the protection of marine life, and the NGT has taken stern action against defaulters. In-situ conservation is one of the mechanisms for the protection of species. However, it is necessary to mirror the habitat of the organisms.”
Understanding Sources And Tackling Tarballs
According to Deoras, scattered data was one of the biggest hurdles to overcoming the challenge. “You have years when tarball quantities are more compared to others. If we had verifiable data on tarballs, it would help find a solution to the issue.”
“The unavailability of information is owing to a shortage of reliable and scientific monitoring and assessment of marine debris at both international and national levels. The Indian Coast Guard has a mandate to provide reports to the Ministry of Defence, Ministry of Shipping and other allied Ministries as and when an instance of an oil spill occurs. Moreover, the NGT may also constitute committees and ask for detailed reports to be submitted to it in the event of oil spills. Hence, there is a mandate for the generation of reports and information on oil spills on the part of the state. However, not all of them may be available in the public domain,” Sairam Bhat said.
NIO’s Suneel Vasimalla says that the CSIR-NIO, in collaboration with the Indian Coast Guard and the Central Pollution Control Board, will study the tarball sources. The Ministry of Environment, Forest and Climate Change will fund this study. “Considering all possible scenarios, we want to identify the source of the tar balls and all possible oil spills. And then the second thing is we have to review the current understanding of the tar ball sources along the west coast of India with respect to global practices. And the third thing is we must prepare a standard operating procedure for each oil spill source. We are going to frame administrative frameworks for each nodal agency and its responsibilities,” added Vasimalla.
