The Mass Rapid Transit Authority of Thailand (MRTA) last week began the search for a private sector partner for the development of its $6bn Orange Line extension of the Bangkok metro. The plan is to build a 40km line, divided into a west and an east section. The MRTA’s tender is for the west element, which will run from Bang Khun Non, a metro station on the Blue Line in the centre of Bangkok to the eastern suburb of Suwinthawong.

The project will involve 27km of tunnels and 8.9km of elevated track. The entire line will have 28 stations, of which 21 will be underground.

According to the tender document, the public sector will take care of land acquisition and the private sector partner will fund, design and build the line in return for a $2.8bn subsidy and 30-year concession for the operation of the line.

At present, the Bangkok metro consists of two lines, Blue and Purple, with another three planned. The eastern section of the Orange Line is presently under construction and is expected to begin operation in 2024.

The document requires that the bidding company be at least 35% owned by a Thai company. The deadline to submit responses is 27 July 27.