India’s longest double-decker viaduct to come up in Chennai

The Tamil Nadu Government has given in-principle approval to the National Highways Authority of India (NHAI) to construct India’s longest double-decker viaduct in Chennai. The 6-lane, 18.4-kilometer elevated corridor will stretch from Kilambakkam Bus Terminus (KCBT) to Mahindra World City (Chettipunyam), with pillars designed to accommodate a future metro line. This ambitious infrastructure project aims to reduce congestion, improve connectivity, and boost the city’s transport efficiency.

The project will follow the proposed 15.46-kilometer Airport–KCBT Metro line, with the next phase extending the metro from KCBT to Chengalpattu. The Detailed Project Report (DPR) will be revised before the tenders are invited. Once completed, this double-decker viaduct is expected to become a landmark engineering achievement and a key facilitator for Chennai’s urban mobility.