Independenta

The incident

On 15 November 1979, the Independenta was travelling from Libya to Istanbul with 94,000 tonnes of Libyan crude oil onboard. Meanwhile, the Greek vessel Evrialy was carrying 7,400 tonnes of steel bars. The two vessels collided at the southern entrance to Bosphorus Strait. Istanbul, which was less than two kilometres away, was at risk.

The collision caused a massive explosion. The windows of homes up to six kilometres inland were smashed and the two vessels went on fire.

The fire onboard the Evrialy was brought under control the same day and the vessel grounded off the European coast of Istanbul. The Independenta was a more complicated case. The explosion risk was high and prevented personnel from approaching the vessel. Following the collision, the Independenta broke in two and its stern section sank. Its cargo of oil escaped, some of which fed the fire while the rest drifted in the form of ignited slicks. Fire fighting operations were ineffective and the bow section of the tanker continued to burn until 14 December. The final explosion occurred on 6 December.

South-easterly winds pushed the burning oil slicks towards the Turkish shores. Popular tourist areas and important economic areas were at risk.

Spill response

Booms were deployed around the burning Independenta to contain the oil, as well as around sensitive sites to protect the ports of Istanbul and Haydrapasa.

Dispersants were sprayed onto the oil from Turkish navy vessels.

Response equipment was provided by the UK and expertise from ITOPF was requested by the Turkish Government. Despite boom deployment, an estimated 50 tonnes of oil reached the port of Haydrapasa.

The majority of the pollution went up in smoke or dissolved in the water column, in the Sea of Marmara. Only a few neighbouring beaches were affected.

Consequences and lessons learnt

The captain and seven members of the Evrialy's crew were arrested. They were accused of not respecting international navigational rules, thereby endangering Istanbul and causing the death of 42 men. Only 2 of the 44 crew survived.

Bosphorus Strait is a very busy waterway and is increasingly used by oil tankers travelling between the Mediterranean and the Black Sea. This heavy shipping traffic generates major risks of oil spills. This incident gave rise to a study that aimed to simulate incidents and pollutant drift in the Bosphorus Strait. This study draws upon the General NOAA Oil Modeling Environment (GNOME). It aims to optimise response actions in order to preserve certain sensitive areas of the strait.

Sources:

- N. Hooke, Maritime Casualties 1963-1996, p. 287
- Alain R. Bertrand Transport Maritime et pollution accidentelle par le pétrole.  Faits et chiffres (1951-1999), p. 95 et p. 99
- OSIR: Oil Spill Intelligence Report:
- Tankers collide in Bosphorus strait, 14/11/1979
- Tanker explodes after collision with freighter near Istanbul, 23/11/1979
- Romanian tanker still burning off Istanbul, 30/11/1979
- Independenta burns out in Bosphorus strait, 28/12/1979