Click it and Unblock the Notifications
Construction of the underground section for Chennai Metro Rail Phase II is expanding to more areas in the southern part of the city. After completing the underground tunnel between Light House and Thirumayilai a few months ago, Chennai Metro Rail Limited (CMRL) is now preparing to begin work on the
next stretch from Thirumayilai to Boat Club. The tunnelling work is expected to start in the first week of August, although it was originally planned to begin in June.
Chennai Metro Phase II Inclusions
The 118.9-km Chennai Metro Phase II project includes three corridors: Madhavaram to SIPCOT (Corridor 3), Poonamallee to Light House (Corridor 4), and Madhavaram to Sholinganallur (Corridor 5). The new 2.2-km underground section between Thirumayilai and Boat Club is part of Corridor 4.
Assembling of Two Tunnel Boring Machines by CMRL
CMRL is currently lowering and assembling two Tunnel Boring Machines (TBMs) at the Thirumayilai station. Once ready, both machines will dig tunnels passing through Alwarpet and Bharathidasan Road stations before reaching Boat Club station. The machine for the down line will begin work first, followed by the one for the up line.
Officials explained that the tunnels between Thirumayilai and Bharathidasan Road will be built in a stacked pattern, where one tunnel is above the other instead of both being side by side. This design is used in places where there is limited underground space or other construction challenges.
CMRL officials said the TBMs are expected to face hard rock as well as clayey soil in the first part of the route. Drilling through hard rock may slow the work because the cutter discs on the machines will need to be replaced more often. After crossing Bharathidasan Road, the machines are expected to pass mostly through clayey soil, allowing the work to move faster.
According to officials, it will take around 18 months to complete the underground tunnelling between Thirumayilai and Boat Club. This work is an important step in expanding Chennai's metro network and improving public transport across the city.