The pipeline will be built at a distance of more than 110km from the Turkish coast, in water depths of about 2,200m and the initial string is planned to be laid starting from late 2014.
The first pipelaying vessel will enter the Turkish exclusive economic zone in the first quarter of 2015 while the first offshore pipeline is expected to start operations by the end of 2015.
South Stream project aims to diversify natural gas export routes and remove transit risks.
The offshore section of the pipeline will feature four strings, each more than 930km-long, to be laid under the Black Sea.
South Stream’s offshore section is constructed by South Stream Transport, a joint-project company between Gazprom (50%), Italy-based Eni (20%), German Wintershall (15%) and French EDF (15%).
The International Energy Agency (IEA) predicts that natural gas demand in the European Union (EU) will increase to between 592 billion cubic meters and 640 billion cubic meters in 2030 from 536 billion cubic meters in 2010.