Technical bids for 21-km tunnel including undersea stretch opened for Mumbai-Ahmedabad bullet train

The technical bids for the construction of a 21-kilometre tunnel, 7 kilometres of which will be under the sea, as part of the Mumbai-Ahmedabad high speed rail corridor, popularly called the bullet train project, was opened on Thursday, an official said.

Two bids have been received from Afcons Infrastructure Limited and Larsen & Toubro Limited for the C-2 package between Bandra-Kurla Complex in Mumbai and Shilphata in Thane district, a National High Speed Rail Corporation Limited spokesperson said. After technical evaluation, financial bids will be opened, the spokesperson added.

As per NHSRCL, which is helming the ambitious project, the tunnel will be a single-tube twin-track structure having a diameter of 13.1 metres at depths ranging from 25-40 metres below the ground.

Of its 20.37 kilometre length, three tunnel boring machines (TBMs) will build 15.42 kilometres of the structure, while the remaining 4.96 kilometre stretch will see the work being done as per the New Austrian Tunnelling Method (NATM).