The Amoco Cadiz Spill – A Supertanker Disaster

Image Courtesy: National Geographic

When super-tankers heavily loaded with oil crash, the environmental cost is always high and the global media spotlight bright. These ships transport vast amounts of oil across oceans and are essential to global trade but one wrong move can result in a massive disaster. An oil spill brings with it not just monetary losses but also proves detrimental to marine life and beaches.

The Amoco Cadiz Oil Spill Disaster occurred on March 16, 1978, when Amoco Cadiz, an oil tanker, split into three and sank into the sea. The ship was traveling from the coast of Brittany in France when it tipped over two hundred thousand tons of rock (crude) oil near the Brittanie coast line, near to the waters of the English Channel. The oil tanker ultimately  ran aground on Portsall Rocks, 5 km from the coast of Brittany, France, all together resulting in the largest oil spill of its kind in history to that date.

Amoco Cadiz carried about 220,000 tons of light crude oil that had been obtained from Ras Tanura, Saudi Arabia and Kharg Island in Iran. All the crude oil that belonged to Shell and 4000 tons of fuel oil that was being ferried by the ship was all spilled due to the harsh weather conditions at the sea which led to the breaking of the ship.

Attempts to save the ship’s cargo and oil were waylaid when storms caused the Amoco Cadiz to split in two, releasing all the oil on board into the Atlantic Ocean, just off the Brittany coast. The isolated location of the ship and the rough sea restricted the cleanup efforts for the first two weeks after the incident. As much as 220,000 tonnes of oil flooded the sea – the entire 1,619,048 barrels on board the ship – creating an oil slick 30 km wide and 130 km long and polluting 320 kms of coastline in the process. More than 30 ships tried to contain the oil slick, including Royal Navy tugs and a special vessel from Holland equipped with mechanical shovels. Although the clean-up operation did manage to collect as much as 100,000 tonnes of oil and water, less than 20,000 tonnes of oil were recovered from this liquid after treatment in refining plants. The oil slick was responsible for killing or injuring an estimated 300,000 sea birds.

The northwesterly winds contributed a great deal in the quick spreading of the oil on the sea surface. The winds spread oil through the 72 km of the French shoreline. In the following month, the westerly winds furthered the spreading of the oil eastwards of the coast. Just a week after the accident, the oil had spread all the way to Cote’s d’Armor.

In 1978, it was estimated to have caused USD 250 million in damage to fisheries and tourist amenities. The French government presented claims totalling USD 2 billion to United States courts.

In subsequent legal proceedings in Chicago, United States, the owners of the tug were held to have been completely blameless while France was awarded USD 120 million from the American oil company Amoco in 1990.

Being the largest oil spillage in the sea, the Amoco oil spill disaster has had adverse effects, especially on the marine life. The oil spillage led to the largest ever loss of marine life in the first two months of its occurrence. Just two weeks after the spillage, millions of sea urchins, mollusks and other small organisms living in the bottom of the sea were killed. Approximately 9000 tons of oysters were also killed.

Birds of the sea were also largely affected, especially in their flight ability. The oil clung on the feathers of the wings of the birds making it difficult for the birds to fly in search of food and other necessities for survival hence leading to the death of many of them.

The live fish that were caught had a lot of disorders on their skin surfaces. These disorders included ulcerations and tumors. The fish caught in the area tasted like petroleum, due to their intake of affected organisms and water. Internally, the fish were also contaminated with the oil and the fish being consumed by human beings would have led to adverse effects.

Echinoderm and small organisms that belonged to the group of crustacean were almost eliminated from the sea. Luckily, they multiplied quickly and their population was restored within a year.

The oil eroded affected beaches. In fact, erosion is still evident in some of the affected beaches.

References: World Atlas, National Geographic, Wikipedia, YouTube

Sea News Feature, May 2