Southern Railway has completed the final location survey (FLS) for a proposed fourth railway line between Tambaram and Chengalpattu, spanning 31 km and designed for speeds up to 160 kmph—the first in the region to exceed the typical 110 kmph design standard. 

The new line aims to ease capacity constraints on the existing network, which currently limit the addition of suburban services despite rising commuter demand. This congestion has forced many to rely on private vehicles, worsening traffic on GST Road. The new line will enable separate tracks for suburban and express trains, enhancing efficiency. It will be built on the eastern side of the existing lines to minimise land acquisition costs and will feature full fencing for safety. 

The estimated cost is Rs 713.4 crore, and further, the Railway Board’s project evaluation committee is reviewing the FLS report. The Tamil Nadu government, through CUMTA, has urged for fast-track approval, highlighting increasing passenger demand along the corridor.