Indias Longest Double-Decker Viaduct Planned for Chennai
Chennai is set to get India’s longest double-decker viaduct, with the Tamil Nadu government granting in-principle approval for an 18.4-km integrated transport corridor. The proposed structure will run between the Kalaignar Centenary Bus Terminus (KCBT) at Kilambakkam and Chettipunyam near Mahindra City along GST Road.
The project, to be executed by the National Highways Authority of India (NHAI), will feature a six-lane elevated highway on the lower deck, while the upper deck is designed to accommodate a future metro rail corridor. Specially designed pillars will support both road and metro infrastructure, enabling seamless integration of transport modes.
Once completed, the viaduct is expected to become the longest double-decker structure of its kind in the country and could even rank among the longest globally. At present, the longest double-decker viaduct in the metro category is a 5.6-km stretch on Kamptee Road under the Nagpur Metro project.
The proposal was cleared during a recent high-level meeting chaired by the Chief Secretary, with participation from officials of the State Highways Department, Chennai Metro Rail Limited (CMRL), NHAI, and other concerned agencies.
Chennai already has experience with such infrastructure, with a 3-km double-decker viaduct currently operational between Moolakadai and Ramapuram.
