Kolkata: The East-West Metro is exactly 300 m away from the riverbed. It has crossed the Howrah station and is ready to enter the final lap to go under the Hooghly.
One of the two tunnel-boring machines (TBMs) was pressed into service on Monday; the other is expected to resume boring work this week after routine maintenance. This is the first time in the country that boring for a railway tunnel under a riverbed is being done. The work under the Hooghly river is likely to start by January and end by September 2017 when the the machines reach the other side of the river.
The Rs 5,000-crore East-West Metro that will link Salt Lake’s Sector V with Howrah Maidan, covering a distance of 16.55 km from eastern part of the city to west, is Kolkata’s biggest infrastructure project so far. For the first time in India, a train will travel under a river — through a 520 m stretch of tracks that will go through a tunnel under the Hooghly river.
Construction of the twin tunnels — with the crown depth being 10m at the start — started in April 2016 from Howrah Maidan. Both the tunnels have already snaked under heritage buildings like Colvin Court and Cambridge Terrace. The tunnels have crossed the railway yard (the depth being 19m at this point) and were in close proximity to the foundation of Bankim Setu safely.
Engineers of Kolkata Metro Railway Corporation (KMRC), the implementing agency of the project, said around 1,200 metres of tunnelling has been done ever since the TBMs were initiated on April 21. “The machines are about 300 metres away from Hooghly. They are expected to reach the river in two months’ time.” The tunnel will cover 520 metres of the riverbed and its crown will be 13m below river bed, where average depth of water will also be 13m.
