Kolkata, August 11, 2026: Kolkata Metro’s Joka-Dharmatala Purple Line has reached a significant construction milestone with the successful completion of the second phase of underground tunnelling on Tuesday.
The Tunnel Boring Machine (TBM) ‘Divya’, developed using indigenous technology, emerged at the surface near Victoria Memorial after completing a challenging 1,740-metre tunnelling stretch.
‘Divya’ began its tunnelling operation on October 11, 2025, and completed the underground stretch in approximately ten months. The achievement is considered particularly significant as the TBM passed beneath or close to several heritage and vulnerable structures during its journey, including Fort William and the Police Training School.
The latest milestone follows the successful tunnelling work carried out earlier by another Tunnel Boring Machine, ‘Durga’, which had already completed its assigned tunnelling operation for the project.
The Joka-Dharmatala corridor forms a crucial part of Kolkata Metro’s Purple Line, which is expected to significantly improve connectivity between southern parts of Kolkata and the city centre.
Metro authorities are now working towards completing the entire Joka-Dharmatala route by December 2029. Once operational, the completed corridor is expected to provide commuters with a faster and more convenient connection across the Purple Line.
The successful completion of the latest tunnelling phase marks an important step in Kolkata’s ongoing Metro expansion and highlights the engineering challenges involved in constructing underground infrastructure in areas surrounded by heritage structures and densely developed parts of the city.
With both ‘Divya’ and ‘Durga’ completing their respective tunnelling operations, the project has moved another step closer to achieving its larger connectivity goals for Kolkata’s southern and central areas.
