Delhi Metro Golden Line: DMRC's Longest Tunneling Milestone.. : Check Route, Completion Timeline, Details

The Delhi Metro Rail Corporation (DMRC) has completed a key tunneling milestone in Phase 4 with the successful excavation of the longest underground tunnel on the Golden Line. The breakthrough took place on December 4, 2024, between Tughlakabad Air Force Launching shaft and Maa Anandmayee Marg, part of the Aerocity-Tughlakabad corridor.

A Tunnel Boring Machine (TBM) named 'AMRIT' completed the 2.65-kilometer tunnel. The TBM, which is 105 meters long, operated at a depth of 16 meters below the surface, boring through challenging ground conditions, including hard rock. The tunnel is lined with 1,894 pre-cast concrete rings, each with an inner diameter of 5.8 meters.

The breakthrough at Maa Anandmayee Marg marks the completion of one of two parallel tunnels for the Aerocity-Tughlakabad section. The second tunnel is expected to be completed by January 2025. The work, carried out by contractor M/s Afcons, is part of the ongoing construction of 19.34 kilometers of underground tracks for the corridor.

The tunneling process involved significant technical challenges, including the relocation of a sewer line and monitoring for ground movements to ensure safety in the densely built-up area. DMRC used Earth Pressure Balancing Method (EPBM) technology, which minimises surface disturbance.

The tunneling milestone is part of the broader Phase 4 project, which will create 40.109 kilometers of underground metro tracks across Delhi.

Key details

• Tunnel Length: 2.65 kilometers
• TBM Used: AMRIT (105 meters long)
• Tunnel Depth: 16 meters
• Concrete Rings Installed: 1,894
• Underground Route: 19.34 kilometers (Aerocity-Tughlakabad Corridor)
• Second Tunnel Completion: January 2025