Thai contractor CH Karnchang Plc has picked Aecom as lead designer for the Orange Line West metro project in Bangkok, billed as one of the biggest rail infrastructure projects in Thailand.

The 13.4km-long line will run from the Thai Cultural Centre to Bang Khunnon with 11 underground stations.

It will connect to the eastern section of the Orange Line, which is currently under construction.

The full, 35.9km-long Orange Line will link Bangkok’s eastern and western districts.

Aecom will design the twin bored tunnels and ventilation systems, trackwork systems and the stations, including structural and architectural works and building services.

“We’re thrilled to be part of Thailand’s efforts to provide better connectivity and transportation for all,” said Ian Chung, chief executive of Aecom’s Asia region.

Aecom has a long history of working with CH Karnchang on Bangkok transit projects including the Blue Line (1997), Blue Line Extension (2011), Orange Line East Section (2017), and Purple Line South (2022).