Chennai Metro Rail’s tunnelling work from Thiruvanmiyur to Indira Nagar for the ongoing phase-II project has begun recently and the machine has drilled nearly 100 metres.
As part of the ₹63,246 crore project, three corridors—Madhavaram to SIPCOT (corridor 3), Light House to Poonamallee (corridor 4) and Madhavaram to Sholinganallur (corridor 5) are being constructed in most parts of Chennai for the past few years.
Under corridor 3, whose network is part elevated and part underground, much like the other two corridors, Chennai Metro Rail has been carrying out tunnelling work for building the underground stretches in small sections. The tunnelling in one small section of this corridor 3, Thiruvanmiyur to Indira Nagar, commenced recently.
According to officials of Chennai Metro Rail Limited (CMRL), the shaft of the station, which has to be built only after which a Tunnel Boring Machine (TBM) can be lowered and launched, was ready and subsequently the machine began the drilling process. For this stretch dominated by high-quality hard rocks, a TBM specialised for operating in such conditions is being utilised.
Officials said, tunnelling through the 650-metre stretch between Thiruvanmiyur and Indira Nagar could be tough and rather slow due to geological conditions, and it would probably require changing the parts of the TBM like the cutterhead more often than expected.
