KOLKATA (Metro Rail News): Kolkata Metro’s Purple Line reached a significant construction milestone on Tuesday when TBM Divya completed its 1.72 km drive from Khidderpore to Victoria. This breakthrough marks the completion of the second underground tunnel in the Joka-Esplanade corridor of Kolkata Metro.
TBM Divya completes 1.72 km tunnel drive
The Tunnel Boring Machine (TBM) Divya broke through at the upcoming Victoria Metro station after finishing its tunnelling drive from Khidderpore. The machine began boring the tunnel on October 11, 2025. It covered approximately 1.72 km to reach Victoria. This latest breakthrough follows TBM Durga, which finished the first tunnel between Khidderpore and Victoria on July 10, 2026. With both machines now completed, the twin tunnels in this section are ready.
TBM Divya at a glance
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| Tunnel Length | 1.72 km |
| Tunnelling started | 11 October, 2025 |
| TBM diameter | 6,60 meters |
| TBM length | Around 95 meters |
| TBM weight | Around 600 meters |
| Tunnel lining | M50-grade precast concrete segments |
Designed for Kolkata’s challenging ground conditions
Kolkata’s soft soil and high groundwater levels make underground construction tough. TBM Divya has been built to work in these conditions while ensuring controlled tunnelling. The project team also used M50-grade precast concrete segments to line the tunnel as the machine moved forward. Metro Railway stated that the construction team maintained safety and quality during the work. They also ensured that surface traffic and regular activities in the busy area continued without interruption.
Purple Line underground work progresses
The Joka-Esplanade Metro corridor will extend Kolkata’s Metro network towards the city’s central areas. Completing the Khidderpore-Victoria tunnel drive is a key step in developing the underground section of the corridor. Further tunnelling and construction activities will continue for the remaining underground parts. The Purple Line is set to improve travel between south Kolkata and the central business district once the corridor is operational.
Officials Highlight Construction Efforts
Prem Sagar Gupta, General Manager of Metro Railway, Kolkata, emphasized that the project team focused on safety and quality while making sure that construction did not disrupt surface traffic and normal activities in the area. Metro Railway called the breakthrough another important move towards completing the underground work on the Purple Line.
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