The 3.82-km tunnel boring work between the Chhatrapati Shivaji Maharaj Terminus (CSMT) and Mumbai Central stations of the upcoming Mumbai Metro III project has been completed, reports Metro Rail News.
The Hindustan Construction Company (HCC) carried out boring the tunnel under the busiest areas of Mumbai on an average rate of 8.20 meters per day.
The tunnel passes through the station boxes of Kalbadevi, Girgaon and Grant Road. The section is part of the 33.50 km long line connecting Colaba-Bandra-SEEPZ (Andheri East).
The project is being implemented at a cost of Rs 23,136 crore, with a loan of Rs 13,325 crore from the Japan International Cooperation Agency (JICA).
HCC was awarded the contract to design and construct twin tunnels by Tunnel Boring Machines (TBMs) along with the construction of four underground metro stations.
“Our teams encountered several geological and urban challenges, including proximity to the Arabian Sea, tunnelling through heterogeneous reclaimed land, congested working areas and drilling below some of the oldest residential and other buildings, many over a century old, without disturbing their foundation,” an HCC spokesperson said.