In a move to streamline metro operations and eliminate mid-journey transfers, Chennai Metro Rail (CMRL) is extending Corridor 5 from Alandur to St Thomas Mount by constructing a new 1.25 km elevated viaduct. The extension will run parallel to the existing elevated corridor, with two tracks for up trains and two for down, transforming it into a full-scale interchange between Corridor 2 (St Thomas Mount–Chennai Central) and Corridor 5 (Madhavaram–Sholinganallur).

Under the original plan, commuters travelling from Madhavaram to southern suburbs like Madipakkam, Medavakkam, or Sholinganallur had to change trains at Alandur. With this new alignment, trains can now operate uninterrupted across corridors, improving efficiency and passenger convenience. To enable the construction, CMRL has acquired additional land and will demolish portions of existing infrastructure near Railway Station Road, modifying curves to accommodate the new viaduct.

A new building and passenger facilities are also planned at Mount station, making it a key southern transit hub comparable to Alandur, as informed by T Archunan, Director (Projects), CMRL. The project gains more relevance as St. Thomas Mount is also poised to integrate with the long-delayed MRTS link from Velachery.