12am-4am curbs on BB Ganguly St stretch till Thurs
Times of India | 5 January 2025
Kolkata: A section of B B Ganguly Street was closed to traffic on Sunday midnight to allow KMRC to check if there are voids along the twin East-West Metro tunnels. The ground stability tests in this particular section of the incomplete Esplanade-Sealdah stretch will go on till Thursday, officials said.
To facilitate the crucial work, KMRC, which is implementing the 16.6 km East-West corridor, 2.5 km of which is incomplete, sought a 12 am-to-4 am traffic block from Kolkata Police for five nights. No vehicles will be allowed between Bank of India crossing and the Nirmal Chunder Street-BB Ganguly Street crossing during these four hours for five nights. Vehicles are being diverted through M G Road and Amherst Street while the geophysical inspection is on, officials said.
"We are cross-checking through geophysical tests to locate voids, if any, in the vicinity of the tunnels passing below the houses in Bowbazar area. If gaps are detected, they will be filled up with superior chemical grouting before continuous train and signal trials begin," a KMRC official said.
KMRC has also started soil testing of the houses below which the tunnels are passing and those within 50-100 m of the twin tunnels. Officials said the testing will be done through sensor-based equipment, by drilling methods, so that any vacuum in the ground around the tunnels can be spotted. "We are being extra cautious to prevent any further incidents of subsidence in the Bowbazar area," an official said.
The inspection will be done along four rows next to the tunnels. Officials said a report will be compiled at the end of the survey and steps taken to ensure that the soil is strong enough to withstand the running of trains loaded with passengers through the Bowbazar cave-in zone. "We can only be sure after conducting geophysical tests and taking adequate measures," an official said.
Track-laying work of the west-bound tunnel, which was affected in the 2019 Aug tunnelling fiasco, was just completed. This was perhaps the last hurdle both KMRC and contractors ITD ITD-Cementation were jittery about. Construction through the 200-m patch surrounding Bowbazar's Durga Pituri Lane, christened the cave-in zone after multiple instances of subsidence, has been a major challenge for the authorities. It is because of this subsidence-ridden area that East-West Metro has been operating in two disjointed stretches — Esplanade-Howrah Maidan and Sector V-Sealdah.
But now the 2.5 km Esplanade-Sealdah section is headed toward completion so that the Green Line or the East-West corridor can be a continuous Metro link from Sector V to Howrah Maidan.