Regular services on this stretch will begin later this year
In a historic moment for India, the Kolkata Metro Railway successfully carried out its first underwater trial run through a tunnel under West Bengal's Hooghly river on Wednesday (April 12, 2023), marking a significant achievement in the country's transportation infrastructure.

The underwater section of the metro is a part of the 16.6-kilometer-long East-West corridor that will connect the twin cities of Howrah and Kolkata. Once this stretch is open, the Howrah Maidan will be the deepest metro station (33-meter below surface) of the country.

The underwater section of the metro consists of a 520-meter-long tunnel, with a diameter of 5.55 meters, built 32 meters below the riverbed. The metro is expected to cover this stretch under the Hooghly river in 45 seconds.

Describing the development as historic, Metro Railway Kolkata General Manager P Uday Kumar Reddy said trial runs on the 4.8-km underground stretch from Howrah Maidan to Esplanade will be conducted for the next seven months, after which regular services o­n this stretch will begin.

The project has been under construction for over a decade and has faced several hurdles and delays. However, the completion of the underwater section is a significant achievement for the Kolkata Metro and has been lauded by several experts in the field.

The project faced several challenges due to the high water pressure, and building a tunnel under the riverbed was a complex task that required meticulous planning and execution. The successful completion of the project is a testament to the hard work and dedication of the team involved in the project.

The underwater tunnel has been constructed using the state-of-the-art tunnel boring machines, which have been specially designed for the project.

The completion of the underwater section is expected to significantly reduce travel time between Howrah and Kolkata. The journey that currently takes around an hour by road is expected to take only 14 minutes by the metro. The East-West corridor is also expected to ease the traffic congestion in the city and provide a safe and reliable mode of transport for commuters.

The Kolkata Metro has been operating since 1984 and currently covers a distance of 27.22 kilometers, with 24 stations. The completion of the East-West corridor is expected to increase the metro's coverage to 31.4 kilometers and connect several important landmarks in the city.

The underwater section is expected to revolutionize transportation in the city, reduce travel time, and provide a safe and sustainable mode of transport for commuters.