This massive undertaking, which may become the largest project of such magnitude in the world, is expected to be completed by 2020.
During a tender that was held on February 13 six companies vying for the construction contract presented their technical and financial proposals, according to Hurriyet newspaper.
The government intends to spend about $1.9 million on the project in 2017 alone and the total cost of the tunnel project is currently estimated at about $8.1 million. Drilling works aimed at determining the soil structure at the construction area are scheduled to begin soon.
The tunnel itself will be divided into three levels: top and bottom levels will contain two-lane motorways while the middle level will house a subway line.
The first stage of this huge infrastructure project involves the creation of a fast subway system that will link the European and Asian parts of Istanbul, while the second stage will culminate in the construction of a two-lane motorway system that connects the TEM road on the western side the Bosphorus with Camlik transportation hub on the eastern side of the strait.