The use of 34 Tunnel Boring Machines (TBMs) in the Capital will be among the highest number of machines used in any urban centre around the same time in any part of the world, according to the Delhi Metro. While in Phase-II, the DMRC has used 14 TBMs for 34.89 km of underground corridors.
Under Phase-III of constructions, 11 TBMs will operate in the upcoming Mukundpur-Yamuna Vihar-Shiv Vihar corridor to build nine underground stations across 19 km. On the Janakpuri-Kalindi Kunj corridor, 16 TBMs will operate to build 14 stations across 24.3 km that will be underground and seven TBMs will operate on the Central Secretariat-Kashmere Gate corridor, which has 9.4 km underground.
Further, tunnels in Phase-III will pass under rail tracks at Palam and Tilak Bridge and near Nizamuddin; tunnels will be made in high ground water level. Phase-III will see tunnels being built under high rise buildings, flyovers along Ring Road and other important locations. While the TBM launching shaft for Naraina Vihar will be made in Delhi Cantonment area due to space limitations near Naraina Vihar, the tunnel below the bio-diversity park at Vasant Vihar, which is rocky in nature, will also be constructed using a TBM.
Among the longest stretches are South Extension-Lajpat Nagar (1.56 km), Palam to ramp before Sadar Bazar (1.5 km) and Dabri Mor to Dashrathpuri (1.4 km).
