Indian Rail has begun tunnelling work on the Rs48.74bn ($993.5m) East-West Metro Corridor Project of the Kolkata Metro to link the IT hub Sector V in Salt Lake near Hugli-Chuchura, to Howrah across the river Hooghly in West Bengal state.
The metro rail project, which was delayed for several months, will now be implemented by Indian Railways and the West Bengal government with funding support from Japan International Cooperation Association.
The 14.67 km Metro line which includes 8.9 km underground and 5.77 km elevated will be built and maintained by Kolkata Metro Rail Corporation (KMRC), with the Indian Railways holding the majority stake.
KMRC managing director Subrata Gupta was quoted by PTI saying that two machines brought from Germany would be used for tunneling.
"In the first phase, we will dig two tunnels, one each for the up and down lines, which will start from Subhash Sarobar and terminate at the existing Central Station," Gupta said.
Started in February 2009, the East West Metro Railway, was expected to be completed by December 2014 in two phases each covering a distance of eight km.
The metro line will have 12 stations, six of them elevated and the rest underground, while the 460m track between Mahakaran and Howrah Station would run under the Hooghly River.
The Metro will be connected to the existing North-South Metro at the central station.