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 Olympic Alliance

SpillsOlympic Alliance

The incident

On the morning of 12 November 1975, the oil tanker the Olympic Alliance and the Royal Navy Frigate HMS Achilles collided in Dover Strait, whilst sailing in thick fog. This resulted in two holes in the starboard tank N°5 of the tanker. The first hole was situated just below the deck line and the other around one metre below waterline. The Olympic Alliance lost about 2,000 tonnes of oil just after the collision.

Despite this, both vessels later continued on their way towards their respective destinations, the HMS Achilles to Portsmouth and the Olympic Alliance to Wilhemshaven in Germany. The latter however lost an additional 10,000 tonnes of oil on her way. She arrived in Germany on 15 November and anchored off Wilhemshaven. On 18 November a decision was made to pump oil from tank N°5 and to transfer it into other tanks in the ship. When the operation was complete, the Olympic Alliance was allowed to sail into the harbour for unloading.


Response operations in accordance with the British contingency plans were organised immediately. A response centre was set up in Dover. A tug and three fishing vessels were sent on site to start spraying dispersants. Another tug from Southampton and a Royal Navy vessel were also on their way. The following day ten vessels were involved including two French vessels. A plane was also sent out to assess the situation and to determine the Olympic Alliance's position. During these flights, response personnel noticed that the oil tanker was still losing oil. In total, 300 tonnes of dispersants were used at sea, on the collision point and in the Olympic Alliance's wake.

Unfortunately response at sea was not sufficient to keep slicks from reaching the coast. On 13 November, oil polluted more than 30 km of coastline in the region of Dover and Folkestone. A floating boom failed to prevent oil from entering Folkestone harbour, and only part of the oil was successfully contained. Dispersants were sprayed on the boomed oil and, at low tide, on oiled areas. Damaged shorelines were cleaned using chemical and mechanical techniques. Cleaning operations ended on 18 November.


77 birds were found dead and a large number were oiled. Murrelets, razorbills and cormorants were particularly affected. However, many were only slightly contaminated and some cleaned themselves by preening.

Name: Olympic Alliance

Date: 12 November 1975

Location: England

Accident area: Dover Strait

Cause of spill: collision

Quantity transported: 216,000 tonnes

Type of pollutant: Iranian light crude oil

Quantity spilled: 10,000 tonnes

Ship type: oil tanker

Date built: 1970

Shipyard: Japan

Length: 324.43 m

Width: 48.25 m

Draught: 24.99 m

Flag: Liberian

Owner: Vinke & Co

P&I Club: West of England Ship Owners Mutual Protection and Indemnity Association


The shipowner and the master were liable for all the cleaning operations resulting from the incident. The shipowner was a member of ITOPF (International Tanker Owners Pollution Federation), and the TOVALOP (Tanker Owners Voluntary Agreement concerning Liability for Oil Pollution) insurance system was used for the compensation.


  • NOAA, Oil spill case histories 1967-1991, Report No. HMRAD 92-11 to the US Coast Guard Research and Development Center
  • IFP, Banques de données sur les accidents de navire ayant provoqué un déversement de pétrole en mer supérieur à 500 tonnes, 1975-1979, Réf. 26 714, Janvier 1979
  • Department of Trade, Accidents at Sea Causing Oil Pollution, Review of Contingency Measures, London, 1978
  • Rijkswaterstaat - Directie Noordzee, "Olympic Alliance" oil spillage, november 1975, NZ-R-77-00

Last update: April 2006

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