Chennai Metro's Phase II Project Has Seen 35% of Progress in Constructing Underground Tunnels

Nearly 35% of the underground tunnels for Chennai Metro's ₹63,246 crore Phase II project have been completed. The Phase II expansion covers 118.9 km across three main corridors, Madhavaram to SIPCOT (Corridor 3), Light House to Poonamallee (Corridor 4), and Madhavaram to Sholinganallur (Corridor 5). Out of the total 69.05

km of underground tunnels planned, 24.2 km have already been built.

Metro Corridors and Underground Sections

The Madhavaram-SIPCOT corridor has the largest underground section, a total of 43.04 km of tunnels to be constructed. So far, 16.2 km have been completed. The Light House-Poonamallee corridor requires 16.29 km of tunnelling, of which 7.56 km has been completed. In the Madhavaram-Sholinganallur corridor, only 9.2 km is underground, but due to earlier delays in contract work, just 0.48 km has been finished so far.

Progress of Tunnelling Process

Officials from Chennai Metro Rail Limited (CMRL) stated that tunnelling is now progressing rapidly. In October alone, three tunnel boring machines (TBMs) completed their drives, between Greenways Road and Mandaveli, Royapettah and Dr. Radhakrishnan Salai, and Panagal Park to Kodambakkam. In the coming months, several more TBMs are expected to finish their tunnelling at locations such as Perambur, Moolakadai, Kellys, Kilpauk, and Thirumayilai. New TBMs will also be launched from Thiruvanmiyur, Chetpet, Perambur Barracks Road, and Kolathur.

The tunnelling process in Chennai has seen both smooth and challenging stretches. In areas T. Nagar, Kodambakkam, Perambur, Adyar, and Chetpet, machines had to dig under flyovers, railway lines, and water bodies. Between Light House and Thirumayilai, tough rock conditions caused repeated damage to TBM parts, slowing down progress. Despite these difficulties, officials remain confident about the steady progress of tunnelling in the coming months.