Tunnel Boring Machine (TBM) Mullai has achieved breakthrough at the North Shaft of Kolathur station for package CP06/UG06/RT01 under the Chennai Metro Rail Phase II Project. It was commissioned at the Kolathur ramp in May 2025 and travelled for 246 metres till the North Shaft.
Besides, TBM Kurinji has been commissioned at Kolathur South Shaft and will travel for 1.06 km till Srinivasa Nagar station under the same package.
Package CP06/UG06/RT01 involves construction of underground stations at Kolathur Junction, Srinivasa Nagar, Villivakkam sub-urban station (Villivakkam), Villivakkam Bus Terminus and Nathamuni (Villivakkam MTH road) with entry/ exit, ventilation shafts, plumbing, earth mat, architectural finishes and signages etc. including twin bored tunnels from Kolathur Junction retrieval shaft to Nathamuni (Villivakkam MTH road) launching shaft and ramps with U-section in Corridor-V. The package was awarded to Tata Projects Limited in September 2023.
The project involves development of 118.9 km of three metro corridors (Corridor III, IV and V) in Chennai, Tamil Nadu at an estimated cost of Rs 632.46 billion. It is mostly underground with an elevated section confined to a few short stretches and consists of 128 stations in total.