Chennai Metro Rail Ltd. (CMRL) has moved a tunnel boring machine (TBM) to the site of the future Chetpet metro station in preparation for the building of two twin tunnels in the core areas of the city.

Tunnelling has already begun in Madhavaram and Greenways Road, and the extension from Chetpet to Nungambakkam covering a distance of approximately 12 kilometre may also start in July.

The TBM will construct one of the twin tunnels at Sterling Road junction, which covers almost 850 metre, just a part of the corridor-3 that extends from Madhavaram Milk Colony to Siruseri Sipcot, a distance of 45.8 km.

The phase-2 expansion of CMRL aims to create a more extensive network covering an area of 118.1 km and 128 stations. It is expected to be ready in stages between 2026 and 2028. With these extensions, the ridership is expected to increase gradually to around four million passengers per day by 2026.

According to CMRL officials, excavation of the shaft at the Chetpet metro site has been completed and a base slab has already been built. The TBM parts are being mobilised, and the machine will be ready to be assembled in June before being lowered into the shaft.

"This will be completed before the end of June. By July, we may start tunnelling," said an official at the site. The shaft will also be part of the Sterling Road junction metro station.

The tunnels will be built at a depth of 22 metre in Chetpet, reducing to 15 metre as it passes through the Sterling Road junction. The stretch between Chetpet metro and Sterling Road junction metro is also part of the contract awarded to build tunnels from Kellys to Taramani covering 12 km on corridor-3.

A total of eight TBMs are going to be deployed to build the tunnels over this stretch.

Tunnelling has already started at the Greenways Road metro station site near the Adyar River, which is also part of the Kellys to Taramani stretch.

The Chetpet metro station will be an interchange, linked with the Chetpet suburban station. It will run across the east of the city and link suburban areas such as Madhavaram Milk Colony and the IT corridor on the Old Mahabalipuram Road (OMR) with more central areas like Nungambakkam, Mylapore, and Adyar.

The vision for Chennai's Metro Rail includes the integration of transit services, the promotion of clean energy usage, and a sustainable solution to combat climate change.

Chennai is one of the fastest-growing cities in India, and with its population set to reach 10 million people by 2025, the transport system is becoming increasingly critical. CMRL believes that a modern, efficient, and integrated public transportation system will be critical to the city's sustainable economic growth and environmental health.