Major breakthrough on the Golden Line as Delhi Metro completes 792-meter tunnel

The completed tunnelling is a significant milestone in DMRC’s Phase IV project, which connects Maa Anandmayee Marg and Tughlakabad.

The Delhi Metro Rail Corporation (DMRC) has completed a 792-metre underground tunnel between Maa Anandmayee Marg and Tughlakabad Railway Colony on the planned Aerocity-Tughlakabad line, often known as the Golden Line, marking a significant milestone in its Phase IV expansion project. This important tunnelling breakthrough was completed at an average depth of 18 metres with a 96-metre-long Tunnel Boring Machine (TBM). The tunnel was built with 566 precast concrete rings, each measuring 5.8 metres in diameter, and used the Earth Pressure Balancing Method to ensure safe drilling beneath metropolitan structures. All precast segments were steam-cured at the Mundka casting yard and assembled with extreme precision. To avoid any disruption to existing infrastructure, high-precision sensors were employed to monitor ground movements during the tunnelling operation.

Dr. Pankaj Kumar Singh, Delhi’s Health, Transport, and Information Technology Minister; DMRC Managing Director Dr. Vikas Kumar; and other senior authorities attended the game-changing event. A second parallel tunnel for the opposite track is already under construction and is planned to be completed in July 2025. The Aerocity-Tughlakabad line, which is 25.82 kilometres long, will include 16 stations—12 subterranean and four elevated—and is a key component of the 65-kilometre Phase IV network that has been approved for construction. This corridor accounts for 19.34 kilometres of Phase IV’s total 40.1 km of underground track. With tunnelling work moving quickly, DMRC hopes to have the Golden Line operational by March 2026.

In a similar event, Delhi Chief Minister Rekha Gupta recently announced central government approval for a new 5-kilometre twin-tube vehicular tunnel connecting Mahipalpur near the Dwarka Motorway and Nelson Mandela Road in Vasant Kunj. The project, estimated to cost ₹3,500 crore, is part of a ₹24,000 billion programme to boost regional connectivity and reduce congestion in Delhi. The tunnel, which is designed as a signal-free corridor with three lanes in each direction, is intended to considerably reduce traffic congestion on NH-48, Mandela Road, and neighbouring districts. The National Highways Authority of India (NHAI) will begin building early next year and expects it to take about two years to finish.

These twin infrastructure projects—the Metro tunnel and the vehicular tunnel—showcase Delhi’s ongoing commitment to improving urban mobility via superior engineering and strategic planning. While the Metro tunnel will increase mass transportation capacity between the city’s southern and central areas, the road tunnel promises to improve vehicular flow, cutting commuting times and congestion. Together, these improvements are expected to transform Delhi’s transport system and deliver long-term advantages to both inhabitants and commuters.