Officials said the tunneling work was progressing well despite delays, and work will pick up pace when the additional tunnel boring machines are deployed.
| Photo Credit: File photo
Due to the delay in tunneling in various stretches of the Phase II network, Chennai Metro Rail will shortly procure three additional tunnel boring machines (TBM) to speed up works.According to officials of Chennai Metro Rail Limited (CMRL), the TBM’s will be deployed on three stretches — Thiruvanmiyur to Taramani, Thousand Lights to Anna Flyover, and Mandaiveli to Thirumayilai. CMRL will buy them at an estimated cost of ₹180 crore.In the 118.9-km Phase II project, 23 TBMs are deployed at present. These three stretches fall under Corridor 3, which originates at Madhavaram and ends at SIPCOT with a total distance of 45.8 km. For this corridor, 43.04 km (upline and downline) has to be tunneled. So far, CMRL has completed only 19.68 km, and another 23.36 km of tunneling is pending.This corridor has the maximum length of underground network at 26.7 km in the Phase II project.“Based on the current pace of work, we need only three additional TBMs. If there is further need, we will purchase a fourth machine. These three TBMs will reach the city in the coming months, one after the other,” an official said.The need to get more TBMs for the Phase II network was due to the inordinate delay in the tunneling operations.Factors that significantly contributed to the delay in works include the cancellation of tenders floated for building underground stations, the delay in completing the construction of the station shaft, and the relocation of various types of utilities.But officials said the work was progressing well, and tunneling work would pick up pace when the additional TBMs are deployed. A few TBMs, which were stuck underground due to the delay in station shaft construction, have made a breakthrough. Published - August 10, 2026 05:00 am IST
