Residents of Bowbazar area, where an aquifer brust led to a huge ground settlement during tunneling work for the East West Metro corridor, complained of fresh hairline cracks appearing on their houses, even as the KMRC on Friday sought to allay fears, saying those will not cause any damage.
A few residents of the area in central Kolkata alleged that hairline cracks appeared on their houses after the tunnel boring work resumed earlier this week.
"We assure that these will not cause any permanent damage to the buildings as all precautions have been taken for the tunnel boring work," Kolkata Metro Railway Corporation (KMRC) general manager, administration, A K Nandy told PTI.
He said the KMRC will repair the cracks and any other damage caused owing to the tunnelling work.
"These are normal hairline cracks, these may happen sometimes. Our engineers are keeping a watch on everything. We will repair everything after the residents come back to their houses," he said, adding that there is nothing to fear.
Residents of several dilapidated buildings have been temporarily shifted to hotels and guest houses as precautionary measure for the tunnelling work.
The tunneling work up to Sealdah will require around five months, according to the head of a committee of experts appointed by the KMRC, the executing agency for the East West Metro corridor project.
With a key machine damaged beyond repair in an accident in August, underground tunnelling work for the East West Metro corridor is likely to take 10 more months, according to the committee.
Safety of the people living in dilapidated buildings, many of which were built over 120 years ago, in one part of the route is a cause for concern, Leonard John Endicott, a geotechnical expert and head of the committee said last week.
The tunnelling work was put on hold after one of the two TBMs hit an aquifer on August 31 leading to severe ground subsidence and collapse of buildings.
With the TBM getting damaged beyond repair in the accident, the work will have to be completed with one TBM only.
Prior to the accident, two TBMs were working parallelly, boring tunnels for the up and down lines of the East West Metro corridor.
"It will take around five months for the TBM to go up to Sealdah from Bowbazar. Thereafter, it will take three months for the TBM, which is a huge machine, to turn around.
"It will take another two months for the machine to dig on the other side and reach up to the point where the first TBM had cut the tunnel," the geotechnical expert had said.
The Calcutta High Court had on February 11 allowed resumption of tunnel-boring work for the East West corridor.
Accepting a report by IIT-Madras, the court had allowed the KMRC to restart operations in Bowbazar, in consultation with the institute.
On February 13, the 4.88km-long first phase of the East West Metro, connecting information technology hub of Sector V in Salt Lake to the Salt Lake Stadium, was opened to public.
Inaugurating the service, Railway Minister Piyush Goyal had said the entire 16.5-km stretch of the corridor - from Sector V to Howrah Maidan - is likely to be ready in two years.
The East West Metro corridor was earlier scheduled to be completed by June 2021.