Kolkata Metro has achieved a key construction milestone on its upcoming Purple Line with the completion of a 1.6-km tunnel between Kidderpore and Victoria Memorial, a critical section of the corridor that will eventually connect Joka with Esplanade.
The breakthrough, achieved by tunnel boring machine (TBM) ‘Durga’ at Victoria Metro station on Friday, marks the completion of one of the two parallel tunnels being built between Khidderpore and Victoria. The tunnelling work began on July 10, 2025, and was completed in about a year.
Railway Minister Ashwini Vaishnaw hailed the achievement, highlighting the engineering complexity involved in constructing metro infrastructure beneath one of Kolkata’s busiest and most historically significant areas.
“TBM Durga achieves breakthrough at purple line of Kolkata Metro,” he wrote on X.
Twin tunnels to connect key stretches of the Purple Line
The completed tunnel forms part of the 15.1-km Joka-Esplanade Metro corridor, which is expected to improve connectivity between Kolkata’s southwestern suburbs and the city’s central business district once fully operational.
Currently, metro services on the Purple Line are operational between Joka and Majerhat. The remaining stretch is under various stages of construction, with tunnelling playing a crucial role in connecting underground sections through densely built urban areas.
According to Kolkata Metro, two tunnel boring machines—’Durga’ and ‘Divya’—have been deployed to construct twin tunnels from Khidderpore to Park Street. Beyond Park Street, the alignment will be built using the conventional cut-and-cover method, depending on site conditions and engineering requirements.
Underground engineering with minimal disruption
Officials said the breakthrough reflects the project’s focus on carrying out complex underground construction while minimising disruption to traffic and daily life on the surface.
Kolkata Metro General Manager Prem Sagar Gupta praised the execution team for maintaining safety and efficiency throughout the tunnelling process.
“Metro Railway infrastructure projects contribute to the nation’s development and for a ‘Viksit Bharat’ with modern public transportation,” said Gupta, who was present at Victoria Metro station when the work was completed.
He also lauded the commitment and teamwork of the project personnel who “ensured safe, methodical, professional and efficient tunnelling”, without disturbing the surface traffic movement.
According to officials, the entire 15.1-km Joka-Esplanade Metro corridor is targeted for completion within the next three years. Once operational, the line is expected to significantly improve east-west connectivity, reduce travel time and strengthen Kolkata Metro’s expanding urban transit network.