Piling Underway for Kolkata Metro’s Bowbazar Shaft

Workers from ITD-ITD Cementation India Ltd JV have over the past quarter been performing piling work deep inside Kolkata’s infamous Bowbazar neighborhood to build a mid-shaft for Kolkata Metro’s 16.34 km east-west Line-2 which will connect Howrah Maidan with Sector V.

This important ’emergency’ mid-shaft wasn’t part of the original tunneling plan, but became necessary to construct after TBM Chandi, a Ø6.65m Herrenknecht earth pressure balance (EPB) machine, hit an aquifer in August 2019 while tunneling for the west-bound tunnel from Esplanade to Sealdah.

This lead to heavy soil displacement and triggered the collapse of several residential buildings in Durga Pituri Lane over a month’s period. Several other buildings developed cracks and more than 600 people had to be evacuated to raze the structures.

Indicative route of Line-2’s Esplanade – Sealdah section – view Kolkata Metro route map and information

After clearing out debris, among other construction equipment, ITD deployed a 90 ton Bauer BG36 piling machine from Austria in August 2020 to carry out piling work for this shaft which will be 20 meters deep.

Here are some snaps of the shaft which will be 35 meters long and 10 meters wide. Soil excavation is planned to commence in February.

Secant guidewall
Rebar reinforcement cage getting lowered

First TBM Chandi (facing east towards Sealdah) will be pulled out and then TBM Urvi, which just started its journey from Sealdah to the shaft on Monday, will be pulled out.

Back in 2017, Delhi Metro faced a similar issue on the Pink Line when CEC-CICI’s two Herrenknecht machines (S780, S781) got stuck in north Delhi’s Rameshwar Nagar. The team then borrowed and deployed two TBMs (S495, S496) to build the pending twin tunnels from the other end, and then pulled all four machines out from what was known as the Gurdwara Shaft. Read all about that saga here.

For more updates on India’s metro systems, check out my Home Page!

– TMRG

written by

Global traveler who prefers mass rapid transit

7 Responses to "Piling Underway for Kolkata Metro’s Bowbazar Shaft"

  1. Shubajit says:

    👍

    Reply
  2. Rupraj Sengupta says:

    As tunnel construction stopped 1st September 2019,the under conscrution ventilation shaft at subodh mullick square lies abandoned!

    Reply
    • TMRG says:

      Interesting. Any idea if they still plan to pursue it? Or will Bowbazar now serve that purpose?

      Reply
      • Showmik Dutta says:

        Will the Kolkata metro east west line construction end and open for public in 2021 December?
        And please give us some updates on Howrah-Maidan to Dankuni and Dankuni- Serampore metro line in Kolkata.
        thanks in advance TMRG.
        God bless you.

        Reply
        • TMRG says:

          I see it opening no sooner than 2023. After and along civil works – various contractors have to complete systems/E&M/architectural work 🙂

          RVNL and WB govt’s first goal is to complete all lines announced in 2010/11. I don’t see new lines or extensions getting pursued anytime soon. You might see announcements here and there for political brownie points, but that’s about it.

          Reply
      • Rupraj Sengupta says:

        They will pursue the ventilation shaft at subodh mullick square it cannot be finished until both up and down tunnels are completed!It is quite a distance sealdah to esplande 2447 mts!

        Reply
  3. Rupraj Sengupta says:

    The retrieval shaft will be closed after the tunnel is completed and the tbms retrieved ventilation will be via shaft at subodh mullick square!

    Reply

Leave a Reply

Want to join the discussion?
Feel free to contribute!

Join the discussion...