Delhi Metro Rail Corporation completes longest twin tunnel in Phase-IV
According to the official statement, the two tunnel boring machines (TBMs), named Bhoomi and Srishti, emerged simultaneously at Pulbangash Metro Station on Wednesday. This marks the completion of the twin tunnels that connect Derawal Nagar to Pulbangash along the Janakpuri West-R K Ashram corridor, which is an extension of the Magenta line.
"Both TBMs were successfully retrieved at Pulbangash Metro Station on Wednesday, after just over 14 months of operation, covering a total length of approximately 2,997 meters at an average rate of 8.2 meters per tunnel per day. This is also the longest tunneling drive (nearly 3 km) in DMRC's Phase IV works," the statement noted.
The event was attended by Delhi's Chief Secretary, Dharmendra, and Dr. Vikas Kumar, Managing Director of DMRC. Anuj Dayal, Principal Executive Director of Corporate Communications at DMRC, expressed pride in this achievement and reaffirmed the organization's commitment to providing safe and efficient transport infrastructure for Delhi's residents.
The contractor, Afcons, is executing the DC-05 package, which includes six underground stations, tunneling of 14.4 km including crossover, ten cross passages, and a 170-meter open and underground ramp. The company stated, "Today, 3 km of twin tunneling has been completed from Derawal Nagar to Pulbangash."
The twin tunnels were excavated at depths of 14-15 meters, passing through densely populated areas such as Rana Pratap Bagh and Punjabi Basti Colony, while also crossing beneath the Najafgarh drain, a structurally sensitive zone. Despite challenges such as tunneling through submerged water conditions and navigating the under-construction Ghanta Ghar station, no structural damage occurred.
The tunnels, with an internal diameter of 5.8 meters, include six cross passages for passenger safety. Civil work for this section was executed by M/s Afcons. The deployment of TBM Bhoomi began on June 18, 2023, followed by TBM Srishti on August 19, 2023.