Construction of the country’s first underwater metro tunnel commenced on the banks of Hooghly river in Howrah of West Bengal.
The tunnelling work under the Hooghly river, the first such under-river project in the country, to provide metro connectivity between Howrah and Kolkata is likely to be completed in 2017.
The tunnel will be a crucial link for the Railway’s 16.6-km-long East-West Metro project in Kolkata.
The 520-metre twin tunnel, one east-bound and the other west-bound, is built 30 metre below the riverbed.
Commuters between Howrah and Mahakaran metro stations will be under the river for only about a minute when the metro train will pass through the tunnel at a speed of 80 km per hour.
The tunnel, work on which started in April 2016, is being built at an expense of Rs. 60 crore. The total cost of the project is estimated to be around Rs. 9,000 crore.
The East-West Metro is scheduled to be operational by August, 2019.
The internal diametre of each tunnel is 5.55 metre and the thickness of the wall is 275 millimetre. The distance between the two tunnels is 16.1 metre.
There will be walkways in the tunnels for evacuation of passengers in case of emergency.
For the Railways, besides the tunnel under the Hooghly river, drilling work is going on for the seven-km-long under–sea route of the Mumbai-Ahmedabad rail corridor to ascertain soil condition for India’s first bullet train path.
Passengers will get the thrill of travelling under the sea at a maximum speed of 350-km-per-hour.