Kolkata Metro has achieved a significant engineering feat as the Tunnel Boring Machine (TBM) ‘Durga’ successfully completed its tunneling work at the Victoria Metro station. This breakthrough, which took place on Friday, July 10, 2026, at approximately 10:30 AM, signifies a major advancement in the development of the Joka-Esplanade Metro corridor, popularly known as the Purple Line (Line 3). The project, which connects Kidderpore to Victoria, has hit this target exactly one year after excavations began on July 10, 2025.
- TBM ‘Durga’ successfully bored a 1.7-kilometer tunnel stretch.
- The tunneling work for this section was completed in exactly one year.
- Sibling TBM ‘Divya’ is expected to finish the second tunnel by the first week of August 2026.
- The next phase involves ‘Durga’ boring a 900-meter section from Victoria to Park Street.
Engineering Excellence and the Purple Line
The Joka-Esplanade corridor is a vital infrastructure project being executed by Rail Vikas Nigam Limited (RVNL). The civil construction for the 5.05-kilometer underground Package UG1 is valued at Rs 2,447 crore and is being handled by Larsen & Toubro (L&T). The breakthrough event saw the presence of top officials, including Metro Railway General Manager Prem Sagar Gupta and representatives from RVNL and L&T.
The TBMs used, ‘Durga’ (S-1410A) and ‘Divya’ (S-1411A), are Earth Pressure Balancing (EPB) machines specifically designed to navigate Kolkata’s soft soil and high groundwater levels. These 95-meter-long, 600-tonne machines are a testament to the “Make-in-India” initiative, as they were assembled in Tamil Nadu using parts imported from Germany’s Herrenknecht. The resulting tunnels feature an outer diameter of 6.63 meters and an inner diameter of 5.80 meters, ensuring robust connectivity for the city.
Future Outlook
With the Victoria station tunnel breakthrough now complete, focus shifts to the remaining underground stations on the line: Kidderpore, Park Street, and Esplanade. As TBM ‘Divya’ nears its own completion date in early August, the project remains on track to transform urban transit in Kolkata, providing a seamless underground link for daily commuters.