Mumbai Metro To Get Its First Under-River Tunnel On Colaba-Bandra Seepz Metro-3 Line; To Be Built Via NATM

Mumbai’s Colaba-Bandra Seepz line will get a 170 metre metro tunnel that will go under the Mithi river. The section between Dharavi and Bandra Kurla complex stations will be the first for Mumbai and India’s second under-river tunnel for a mass transit project.

The project being undertaken by the Mumbai Metro Rail Corporation (MMRCL) runs from Prabhadevi beneath Mahim Causeway or Lady Jamshetjee Road. The 153-metre section of the tunnel at the BKC station will be built by the New Austrian Tunnelling Method (NATM), the tunnelling system designed to use the strength of the soil or geological formation around the tunnel for support.

The tunnel shaped like a horseshoe will be 8.5 metres to 12.5 metres below the riverbed - reports The Indian Express.

Speaking about the project SK Gupta, Director of MMRCL said: “When tunnelling below a water body, you have to almost feel the ground, watch it closely and see how it’s behaving, to understand to what extent it needs to be supported.”

The proposed 33.5 km Metro-3 line will be the second metro in the country to have tunnels under a riverbed. The first is being constructed in Kolkata under the Hooghly River.