In a major milestone for Chennai’s expanding metro network, the tunnel connecting Lighthouse and Thirumayilai is expected to be completed by September this year. The much-anticipated underground link, part of the Chennai Metro Rail’s Phase 2 development, has been in the planning stage for several years and is now nearing completion.The tunnel is set to play a critical role in enhancing urban connectivity, serving as a key component of Corridor 4 in the 118.9 km Phase 2 stretch. This corridor will connect Lighthouse to Poonamallee, covering a total distance of 26.1 km, of which nearly 10 km will run underground. Once operational, this link will greatly improve access to important city zones, including Marina Beach, Thirumayilai, Kutchery Road, T. Nagar, and Kodambakkam.
According to metro officials, the tunnel will eventually support driverless metro trains, with operations expected to begin in about three years. The introduction of automated trains through this tunnel is expected to significantly enhance travel efficiency and commuter experience.
Two massive tunnel boring machines (TBMs), aptly named Flamingo and Eagle, are spearheading the underground work. Flamingo began its 1.96-kilometre tunneling operation from Lighthouse in September 2023, moving through Kutchery Road toward Thirumayilai. Eagle, operating in parallel, is constructing a twin tunnel to support the two-way metro operations.
The ambitious project marks a significant step in the creation of a high-capacity, future-ready transit network for Chennai. Once completed, the Lighthouse–Thirumayilai tunnel will not only ease traffic congestion in the city’s densely populated zones but also provide commuters with faster and more reliable access to the city’s coastline and beyond.