If the contractors stick to deadlines, residents of localities in the city all the way from Madhavaram to Taramani via Ayanavaram can escape road traffic and travel through the underground Metro Rail in five years.
The Chennai Metro Rail had begun construction work a few months ago for the phase II project which has now gained ground as the contractors have started building the diaphragm walls in many locations across the stretch for creating the underground network between Madhavaram and Taramani (falling under the Madhavaram to SIPCOT line of the phase II).
These walls are an important component and have to be raised before the tunnelling work begins. Diaphragm walls, which look like a box-type structure, are one-metre thick and serve to avert any settlement of soil.
According to CMRL officials, it takes nearly 6-8 months to finish building the diaphragm walls and it was quite a complex job. “In many locations, including Madhavaram, Murari Hospital, Ayanavaram, Purasawalkam, Chetpet, Royapettah Government Hospital, Greenway’s Road, the construction of the diaphragm wall has started. The trench cutters to dig deep into the soil have come from Germany and have been deployed in many places. We are in the process of identifying the tunnel boring machines now,” an official said.
The tunnelling work, which is the most challenging in creating the underground stretch, will start by mid next year after the diaphragm wall construction gets over. “This will be a time consuming process taking about 2-3 years. But we have learnt from the mistakes in the phase I project and trying to be cautious in the underground work and will ensure the neighbourhood buildings or roads do not get affected,” he added.
