The tunnelling work in Bowbazar area will recommence in full swing in a day or two, which was put on hold after one out of the two tunnel boring machines (TBM) hit an aquifer last year on August 31, leading to severe ground subsidence as well as collapse of buildings.
Kolkata Metro East-West corridor update: The underground tunnelling work for Kolkata Metro’s East-West corridor is likely to take 10 more months for completion. This is because a key machine has been damaged and is beyond repair, said an international expert committee, appointed by the Kolkata Metro Rail Corporation (KMRC), which is executing the project. Leonard John Endicott, a geotechnical expert as well as the head of the committee, was quoted in a PTI report saying that besides, the safety of those living in dilapidated buildings on one part of the route is a major cause for concern as many of these buildings were constructed over 120 years ago.
According to Endicott, the tunnelling work in Bowbazar area will recommence in full swing in a day or two, which was put on hold after one out of the two tunnel boring machines (TBM) hit an aquifer last year on August 31, leading to severe ground subsidence as well as collapse of buildings. He said that the work will have to be completed with one TBM only with one getting damaged beyond repair in the accident. In order to ensure that there is no repeat of the previous incident, the working TBM has been moved a few rigs to check for all safety parameters put in place. He said that prior to that accident, two TBMs were working parallelly, boring tunnels for the East-West Metro corridor’s up and down lines.
Endicott said that it will take around five months time for the TBM to go up to Sealdah from Bowbazar. Thereafter, it will take a duration of three months for the TBM, to turn around. The geotechnical expert further said that it will take another two months period for the TBM to dig on the other side and then reach up to the point where the first machine had cut the tunnel. He claimed that the working TBM has been upgraded and now it has 50% more capability. This will ensure that the ground holds during the tunnelling work.
The committee head also said that special measures have been taken to make sure that water does not seep into the tunnel. The work will be stopped within an hour of noticing any abnormality during tunnelling in the area, he further said. On the other hand, the damaged machine will be dismantled and it will be taken away from the underground shaft, he added.
Earlier this month, the 4.88 km long first phase of the East-West Metro corridor, connecting IT hub of Sector V in Salt Lake to Yuva Bharati Krirangan Stadium, was opened. Railway Minister Piyush Goyal, while inaugurating the service said that the entire 16.5 km long stretch-from Sector V to Howrah Maidan, is likely to be ready in the next two years.