Chennai Metro Rail Limited (CMRL) is set to begin tunnelling work for Phase II between Kolathur and Villivakkam within the next two weeks, marking a significant milestone in the city's ?632 billion ($7.6 billion) metro expansion.

Phase II comprises three corridors: Madhavaram to SIPCOT (Corridor 3), Light House to Poonamallee (Corridor 4), and Madhavaram to Sholinganallur (Corridor 5). While substantial progress has been made in Corridors 3 and 4, the underground stretch of Corridor 5 has been delayed by over a year.

CMRL officials have confirmed that tunnelling will begin this month at Kolathur, with the tunnel boring machine (TBM) ‘Kurinji’ already in position. This crucial five-kilometre underground section will feature metro stations at Kolathur Junction, Srinivasa Nagar, Villivakkam Metro, Villivakkam Bus Terminus, and Villivakkam MTH Road.

Corridor 5 starts as an elevated stretch from Madhavaram to Retteri before going underground at Kolathur Junction. It will remain underground until Villivakkam MTH Road, after which it resurfaces and continues elevated to Sholinganallur via Madipakkam.

Once operational, the corridor will enhance connectivity for residents of Kolathur and Villivakkam, linking them directly to key locations like Mylapore, Adyar, and the IT corridor along Old Mahabalipuram Road (OMR). Villivakkam will benefit from three metro stations, improving accessibility and reducing travel time.

Preparatory work for tunnelling is in progress, and CMRL officials remain optimistic about the excavation between Kolathur and Srinivasa Nagar due to the mostly clayey soil, with only minor rocky patches near Srinivasa Nagar.