Construction work in top gear, tunnel boring slated to start in March 2025

Kolkata: The underground section of the Joka-Esplanade Metro Corridor (Purple Line), spanning from Mominpur to Esplanade, is progressing rapidly following the resolution of significant challenges. Tunnel boring work is slated to begin in March 2025.

According to an official statement from Metro Railway, two Tunnel Boring Machines (TBMs) will be deployed to construct the twin-tube tunnels, each with an inner diameter of 5.80 metres. The TBMs are being manufactured in a factory located in Chennai with significant use of Local Content under the ‘Make in India’ programme. They are expected to begin operations in March 2025. The 14-kilometre Purple Line currently operates on an 8-kilometre stretch from Joka to Majherhat. The new underground section will extend from Mominpur to Esplanade, with stations between Park Street and Esplanade being constructed using the cut-and-cover method.

The underground track will be situated approximately 17 metres below ground level.

Recently, a significant hurdle for the project was overcome when the Ministry of Defence approved the relocation of BC Roy Market, the site for most of the Purple Line’s Esplanade station. The 528 traders from the market will be temporarily moved to the Mounted Police Club grounds. Rail Vikas Nigam Limited (RVNL) has proposed constructing a permanent market atop the Purple Line’s Esplanade station. In another development, the L20 bus stand is set to be temporarily shifted to Curzon Park in the coming months, pending final approval from the West Bengal Transport Corporation (WBTC).

Kolkata Metro Railway reported that around 1,000 trees in the Maidan area are located in the path of the Cut and Cover tunnels and stations. Rather than felling these trees, efforts are being made to transplant them in order to maintain an ecological balance between development and the environment. Permission for the transplantation has been sought from the Central Empowered Committee (CEC) in accordance with the directives of the Supreme Court.

To provide a clearer picture of the ongoing work, RVNL has set up a Model Room at the Victoria Station construction site. The room features detailed scale models of the alignment, underground stations, tunnel linings, soil profiles, pieces of machinery, safety gears, instrumentation markers and project details.