The Tamil Nadu government gave in-principle approval for an 18.4-km elevated corridor between the Kalaignar Centenary Bus Terminus at Kilambakkam and Chettipunniyam near Mahindra City on GST Road.

Led by the National Highways Authority of India, the project will have a six-lane elevated highway on the lower deck, while its pillars will be designed to support a future metro line above. If built, it will far exceed the current national record of a 5.6-km double-decker metro viaduct in Nagpur. The clearance followed a high-level meeting involving state highways officials, Chennai Metro Rail and NHAI, after earlier concerns over Metro alignment were resolved.

A senior NHAI official said, “The government has granted in-principle approval for constructing the 18.4-km elevated corridor from the KCBT to Chettipunniyam.” The detailed project report is being revised, after which tenders will be floated, with state support planned.