A second underground tunnel on Kolkata’s Purple Line has reached the under-construction Victoria Metro station, advancing work on the difficult central-city section of the Joka–Esplanade corridor. The breakthrough by tunnel boring machine (TBM) Divya completes another major construction stage between Khidderpore and Victoria, bringing the southern suburbs a step closer to a direct metro connection with Kolkata’s core.
The Kolkata Purple Line is being built through one of the city’s most constrained urban environments, where dense development, existing utilities, busy roads and heritage-sensitive areas leave little room for conventional construction. Moving major sections underground reduces the need for extensive surface disruption, particularly around the Maidan and Victoria precinct.Divya has completed the second tunnel on the roughly 1.7-km Khidderpore–Victoria section. Its twin machine, Durga, completed the parallel tunnel in July. The two breakthroughs are significant because they establish the underground passage required for both directions of metro movement on this part of the corridor.The engineering challenge extends beyond excavation. Earlier planning for the corridor was altered to place the Maidan-area section underground, partly to protect the area’s skyline and ecological character. The underground stretches between Victoria, Park Street and Esplanade involve tunnelling between stations, while station areas require different construction methods.
For commuters, however, the value of the Kolkata Purple Line will ultimately depend on more than completing tunnels. The corridor is intended to connect Joka and the southern parts of the city with central Kolkata, creating interchange opportunities with existing metro services around Park Street and Esplanade. Better integration with buses, walking routes and other public transport will determine how effectively the infrastructure translates into shorter and more reliable journeys.The project also highlights a wider urban-planning issue. Kolkata’s future transport expansion increasingly has to balance mobility requirements with heritage protection, environmental constraints and the disruption caused by large construction sites. Underground construction can limit some surface impacts, but it remains expensive, technically demanding and dependent on careful monitoring of buildings and utilities.
The next priority is to advance the remaining underground works towards Park Street and Esplanade, alongside station construction and systems installation. For residents, the real measure of progress will come when the completed corridor delivers dependable, accessible public transport and makes sustainable travel a practical alternative to increasingly congested roads.
