First of its kind, a huge tunnel from Howrah to Kolkata is being planned by Metro authorities. This is for the construction a new metro line across the river. So far, there is no such metro tunnel of this scale in our country. Known to be the harbor of cutting edge technology and innovation, Metro is proving its mettle once again with the new happening.
Kolkata Metro is planning to connect Howrah and Kolkata by two parallel tunnels at a depth of 30m below the surface of the earth and also 13m below the floor of the river. For these gigantic tunnels to dig, East Metro has employed Two Huge Tunnel Boring Machine (TBM) to cut deep inside the Hooghly. These tunnels span over a half kilometer long. However, both of them couldn’t be operated simultaneously due to technical issues.
Three fourths of the 16.6 East Metro route includes underground tunnels. These tunnels of about 5.5m diameter are separated by 16m to 18m across the stretch. A lot of care is being taken while drilling through the ground. Soft clay soil beneath the ground is the main reason for apprehension. Already few incidents took place along the heritage buildings like the Howrah District Library. Many historic buildings are present along the stretch where tunnels are being dug. Kolkata, being one of the oldest cities in India with many 19th century buildings, has a delicate ground to work on.
Kolkata Metro Railway Corporation Limited, the developer for the East West Metro Project faced many hurdles in the due course of the underground project, with few of the structures displaying slight cracks. With many more structures on the way of plan, the authorities are hoping for a fruitful outcome from the project. Fingers Crossed!