Chennai: In a significant move, the Chennai Metro Rail Limited’s (CMRL) ‘Adyar’, the tunnel- boring machine (TBM), is likely to complete work on the second tunnel under Adyar river this week.
According to T Archunan, director (projects), the TBM will be retrieved from the underground shaft located near Malar Hospital before Jan 30.
In February 2023, the CMRL had deployed two tunnel boring machines namely ‘Kaveri’ and ‘Adyar’ to dig 1.2 km of parallel tunnels, according to a report in Times of India.
Adyar TBM’s progress and challenges
The first TBM completed drilling work in September 2024, while another machine was expected to complete drilling by end of November 2024. However, the work on the 300 metres of stretch delayed the drilling process due to presence of hard rock. The cutter heads had to be replaced multiple times due to hard rocks that slowed the work.
The work also proved challenging as the drilling had to be carried under the petrol pump and Ramachandra College, where tunnel depth ranged from 12 to 16 meters below the river. The TMB also navigated a 300-metre stretch of Adyar river.
Of the total 1.2-km stretch of the tunnel drilling, only 16 meters of boring is left. And this is likely to get completed in the next few days.
Two tunnels to connect Chennai’s northern suburbs
These two tunnels when completed, will connect Chennai’s northern areas and IT corridor along Old Mahabalipuram Road (OMR).
Nine of the 23 tunnel boring machines have completed their work. Currently, the drilling is underway at Greenways Road-Mandaveli, Chetpet, and Royapettah for Corridor 3. In this phase, the work on 14-km of the 43 stretch is finished. While 4-km stretch of Corridor 4 (Light House-Poonamallee) is completed. However, the work hasn’t started yet on Madhavaram-Sholinganallur corridor.
