CMRL Completes 48% of Underground Tunnelling for Phase II in Chennai
Chennai Metro Rail Limited (CMRL) has completed nearly 48% of the tunnelling work for the underground sections of its 118.9-km Phase II project, reaching the milestone after three tunnel boring machines completed drilling and recorded breakthroughs across Chetpet, Villivakkam, and Royapettah over three days.
According to CMRL officials, the Phase II project includes a total of 69.05 km of underground stretches spread across three corridors: Madhavaram to SIPCOT on Corridor 3, Poonamallee to Light House on Corridor 4, and Madhavaram to Sholinganallur on Corridor 5. Out of this total underground network, 33.22 km of tunnelling has been completed so far.
Corridor 3 accounts for the largest share of underground tunnelling in the project, spanning 43.04 km. Officials reported that tunnelling on 22.63 km has been completed on this corridor. Meanwhile, about 62% of tunnelling has been completed on Corridor 4, and CMRL has carried out 27% of the tunnelling work along Corridor 5.
The recent breakthroughs occurred on three distinct stretches: Chetpet to Kilpauk Medical College, Villivakkam Railway Station to Villivakkam Bus Terminus, and Royapettah to Radhakrishnan Salai.
On the Chetpet-Kilpauk Medical College stretch, the machine drilled a distance of 685 metres. The operation required tunnelling beneath five active railway tracks near the Chetpet railway station, the Chetpet Eco Park, and Kilpauk Medical College Hospital. The boring machine also navigated 6.1 metres directly beneath the operational Phase I metro tunnel.
On the Villivakkam Railway Station to Villivakkam Bus Terminus stretch, the machine completed a 601-metre tunnel drive. Similar to the Chetpet stretch, the machine had to drill directly beneath five railway tracks located at the Villivakkam railway station.
On the Royapettah to Radhakrishnan Salai section, the tunnel boring machine covered a distance of 915 metres. During this drive, the machine bored beneath multiple surface structures along Royapettah High Road, including Peters Bridge, the Employees' Provident Fund Organisation (EPFO) building, and a school.
