SS Wafra oil spill

History
Name: SS Wafra
Namesake: Wafra
Owner: Getty Tankers
Operator: Overseas Tankship Corp
Port of registry: Liberia
Builder: Nagasaki Works, Mitsubishi Shipbuilding and Engineering Co
Launched: 7 August 1955[1]
Completed: 1956
Identification: 1456
Fate: Sunk by South African Air Force on 12 March 1971 to contain an oil spill.
General characteristics
Class and type: Oil tanker
Tonnage: 27,400 GRT (increased to 36,697 GRT or 68,600 DWT in August 1970)[2][3]
Installed power: 17,600 shaft horsepower (13,100 kW)[1]
Propulsion: Steam turbine

The SS Wafra oil spill occurred on 27 February 1971, when SS Wafra, an oil tanker, ran aground while under tow near Cape Agulhas, South Africa. Approximately 200,000 barrels of crude oil were leaked into the ocean.[4][5] The larger part of the ship was refloated, towed out to sea, and then sunk by the South African Air Force to prevent further oil contamination of the coastline.

Grounding and sinking

Grounding
Cape Agulhas
Western Cape, South Africa

The Wafra left Ras Tanura in Saudi Arabia on 12 February 1971 bound for Cape Town, South Africa, with a cargo of 472,513 barrels[6] (63,174 tonnes)[7] of Arabian crude oil on board.[8][9] Half the cargo was owned by Chevron Oil Sales Co., and the other half by Texaco Export, Inc.[10]

The ship was rounding the southern tip of Africa at 6:30 am on 27 February 1971 when the piping that brought seawater on board to cool her steam turbine failed. The engine room flooded, incapacitating the ship. She was taken under tow the following day by the Russian steam tanker Gdynia, which – finding the task too difficult – handed the tow over to the Pongola 7 miles (11 km) off Cape Agulhas, later the same day.[3] The tow cable subsequently broke, and the Wafra grounded on a reef near Cape Agulhas at 5:30 pm on 28 February. All six of the port cargo tanks, as well as two of the six center tanks, were ruptured, resulting in approximately 26,000 tons of oil leaking at the grounding site, of which 6,000 tonnes washed up at Cape Agulhas.[11] A 20-mile (32 km) by 3-mile (4.8 km) oil spill resulted,[9][12] which affected a colony of 1200 African penguins on Dyer Island near Gansbaai.[13]

The ship was refloated and pulled off the reef on 8 March by the German tug Oceanic, but started to break apart. To prevent further oil contamination of the coastline, the larger section was towed 200 miles (320 km) out to sea to the edge of the continental shelf (36°57′S 20°42′E / 36.950°S 20.700°E / -36.950; 20.700), leaving a 160-kilometre (99 mi) oil slick in her wake. On 10 March 1971, Buccaneer aircraft of the South African Air Force attempted to sink her with AS-30 missiles, but succeeded only in starting a fire. The ship burned for two days before a Shackleton aircraft was eventually able to sink it with depth charges in 1,830 metres (6,000 ft) of water.

If the Wafra had been a twin screw, two engine room ship, loss of an engine would most likely not have caused the loss of the whole ship.[12] At the time, the oil spill was in the top twenty most disastrous tanker spills on record.[12]

Aftermath

In the wake of the accident, the South African Department of Transport realised that despite many Very Large Crude Carriers (VLCCs) using the Cape sea route each year, the authorities did not have ocean-going tugs that were able to assist them in distress, and to protect sensitive marine areas by breaking up oil spills with chemical dispersants.[14] They therefore set up an oil spill prevention service known as Kuswag (Coastwatch) and commissioned two new salvage tugs, the John Ross and Wolrade Woltemade.[15] The two tugs, with their 26,200 horsepower (19,500 kW) engines, held the record as the world's largest salvage tugs.[16]

See also

References

  1. 1 2 商船建造の步み. Mitsubishi Zōsen Kabushiki Kaisha. 1959. p. 124.
  2. ↑ "South African Shipping News and Fishing Industry Review". 26 (1). Thomson Newspapers. 1971.
  3. 1 2 "Casualty List (Casualty ID=19710227_001)". Center for Tankship Excellence. Retrieved 28 December 2011.
  4. ↑ "Wafra". Incident News. Retrieved 23 December 2011.
  5. ↑ "Cape Agulhas, South Africa: Incident Summary". Incident News. 27 February 1971. Retrieved 23 December 2011.
  6. ↑ United States Court of Claims (1980). Federal supplement. West Pub. Co. 477. Missing or empty |title= (help)
  7. ↑ Day, John H.; Cook, F.; Zoutendyk, P.; Simons, R (1971). "The effect of oil pollution from the tanker "Wafra" on the marine fauna of the Cape Agulhas". Zoologica Africana. 6: 209–219.
  8. ↑ American Maritime Cases. Maritime Law Association of the United States. 3. 1980. Missing or empty |title= (help)
  9. 1 2 "Oil Spill Case Histories" (PDF). Washington: NOAA. 29 May 1997.
  10. ↑ Texaco Export, Inc., and Chevron Oil Sales Co. (Plaintiffs-Appellants) vs Overseas Tankship Corp. (Defendant) and Getty Tankers Ltd. (Defendant-Appellee) United Steamship Corp. (Defendant-Third-Party Plaintiff-Appellee) vs Getty Oil Co. (Third-Party Defendant-Appellant), Nos. 308, 438, Dockets 77-7358, 77-7382 (United States Court of Appeals, Second Circuit 2 March 1978).
  11. ↑ Cornell, James; Surowiecki, John (1968). The Pulse of the Planet: A State of the Earth Report from the Smithsonian Institution Center for Short-lived Phenomena. Harmony Books. ISBN 0-517-50065-5.
  12. 1 2 3 Devanney, Jack (2006). The Tankship Tromedy: The Impending Disasters in Tankers (PDF). Tavernier, Florida. p. 110. ISBN 978-0-977-64790-3.
  13. ↑ Hofer, Tobias N. (2008). Marine Pollution: New Research. Nova Publishers. p. 343. ISBN 9781604562422.
  14. ↑ South African Digest. South Africa Dept of Information. 1986.
  15. ↑ Hutson, Terry (31 January 2004). "Historical Review of SA Oil Pollution Service". Ports and Ships.
  16. ↑ Rosenthal, Eric (1982). Total Book of South African Records. Delta Books. p. 71. ISBN 0-908387-19-9.

Further reading

Coordinates: 35°0′S 20°2′E / 35.000°S 20.033°E / -35.000; 20.033

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