Chennai Metro Rail Limited (CMRL) has achieved another key construction milestone on Corridor-4 of its Phase-2 network, with the second tunnel boring machine (TBM) completing its breakthrough at the Thirumayilai shaft.
The downline TBM, named Flamingo, breakthrough happened on Feb.27, marking the successful completion of the first downline tunnel drive between Light House and Thirumayilai, said a note of CMRL.
This breakthrough follows the earlier completion of the upline tunnel by TBM Eagle under the same contract on Feb. 9
The 1985-metre tunnel, executed by Cemindia Projects Limited, passes beneath some of the city’s most sensitive and congested stretches, including the Lighthouse area, the All India Radio campus, the Russian Embassy zone, Our Lady of the Rosary Church, and several heritage and high-importance structures such as the MRTS bridge and Buckingham Canal.
The drive navigated challenging geological conditions, including rocky strata, shallow overburden, deepest overburden due to stacked tunnel configuration, and unforeseen gas pockets.
CMRL deployed two TBMs—TBM Eagle and TBM Flamingo for this section.
With today’s breakthrough, both tunnels on the Light House–Thirumayilai stretch have now been fully completed.
This break will significantly enhance connectivity across Mylapore, Luz and Central Chennai upon commissioning of the Metro services.
Both TBMs known as Flamingo and Eagle will now be relaunched from Thirumayilai for the next drive towards Boat Club.
The milestone events took place in the presence of T. Archunan, director (Projects), CMRL; R. Murali, Chief General Manager, (finanace), R. Ranganathan, General Manager (construction), CMRL; C. Murugamoorthy, Team Leader, General Consultants, along with officials from CMRL and the contracted companies.
