'TMB Durga' emerges near Victoria as Kolkata metro completes Joka-Esplanade tunneling work

The expansion of the Kolkata Metro's Joka-Esplanade corridor achieved a significant milestone on Friday as the massive tunnel boring machine (TBM) named 'Durga' reached the Victoria station area. Exactly one year after beginning its underground operations on July 10 last year, the massive 95-meter-long machine is scheduled to emerge from the ground. Metro workers and engineers expressed great excitement as the critical phase of the construction progressed rapidly beneath the city.

In this first major phase of construction, the TBM successfully dug a 1.7-kilometer-long tunnel from Khidirpur to Victoria. The tunnel runs through highly sensitive zones, directly beneath prominent heritage structures such as Fort William and the Police Training School. Despite the structural challenges above ground, the modern Hydro-Vacuum/Slurry Shield TBM reached its destination smoothly without causing any structural damage to these historic buildings.

The overall project utilizes two state-of-the-art tunnel boring machines, 'Durga' and 'Divya', to construct a joint tube tunnel spanning approximately 2.65 kilometers from Khidirpur to Park Street. While 'Durga' is driving the tunnel toward Park Street and has reached Victoria, 'Divya' is working concurrently along the opposite Jokamukhi line. These advanced machines, each weighing over 600 tons, operate roughly 17 meters below the surface and are equipped with advanced safety systems to ensure rapid, risk-free excavation beneath Kolkata.