BENGALURU: After drilling underground for 419 days between the upcoming Cantonment and Shivajinagar Metro stations, the first Tunnel Boring Machine (TBM) of Phase-II, ‘Urja’, finally completed the stretch of 855 metre on Wednesday.
In the process of drilling over 60 feet below the ground to create a tunnel for the 21.26 km Nagawara-Kalena Agrahara (Gottigere) Line, the Chinese-made machine encountered numerous challenges including the second Covid-19 and seeping of slurry into the buildings forcing a temporary halt in tunnelling. The work executed below a congested area like Shivajinagar which is packed with countless old buildings forced the TBM to operate with enormous caution.
The machine started work on July 30, 2020, in presence of former Chief Minister B S Yediyurappa. The breakthrough was achieved at 10.15 am at Shivaji nagar station in presence of Chief Minister Basavaraj Bommai and other dignitaries.
For the 168 workers who worked 24x7 for 13 months and 23 days with the need to maintain social distancing during the second Covid-19 wave, it was sheer relief. “It is a great day for all of us. We all feel very satisfied, “said Vivek Kumar Pande, who has experience of carrying out similar work for Mumbai Metro.
“We used to be underground throughout our shift with food and water being sent to us below. Sufficient ventilation ducts brought in fresh air from above and we did not feel any breathing issues,” he added. Safety Manager Rohit said, “Tunnelling is relatively tougher than the elevated portion. Covid-19 made things a little complicated prompting us to take precautions. Good to see the breakthrough.”
Mazar Ahmed, Assistant Executive Engineer, BMRCL said, “It will take 60 days for this machine to fully dismantle. It will be transported to Cantonment where it will be reassembled. Drilling work towards Pottery Town will begin next.”
Eight other TBMs are presently working to put in place the tunnels for the underground corridor with 12 stations running for 13.76 km from the South Ramp near Jayanagar Fire station to North Ramp at Nagawara. The remaining 7.5 km of the line will be elevated.