Underwater Bullet Train Tunnel Project in India: 10 facts that will leave you impressed

India is all set to make a significant impact on the global engineering landscape with the construction of a 21 km underwater tunnel beneath the Arabian Sea for its first bullet train service along the Mumbai-Ahmedabad route. This ambitious endeavor is a key component of the Mumbai-Ahmedabad High-Speed Rail Corridor, a visionary infrastructure project set to transform travel between two of India’s major cities.

Let’s have a look at 10 interesting facts about this upcoming project that will leave you shocked:
India’s first: India is set to build its first-ever underwater tunnel for a bullet train, a key part of the Mumbai-Ahmedabad High-Speed Rail Corridor.

Impressive length: The tunnel will stretch 21 kilometers under the Arabian Sea, including a significant 7 kilometers beneath the Thane Creek, an ecologically sensitive intertidal zone.
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Deep dive: Construction will take place at depths ranging from 25 to 65 meters below the sea’s surface, navigating complex geological conditions.


Huge machines: Unlike metro tunnels, which use smaller TBMs with cutter heads of 5-6 meters, this project requires massive Tunnel Boring Machines (TBMs) with 13.1-meter cutter heads.

Dual approach: To excavate the tunnel, three TBMs will dig through 16 kilometers, while the remaining 5 kilometers will use the New Austrian Tunnelling Method (NATM).

Travel time: Once completed, the tunnel will allow the bullet train to reach speeds of up to 320 kilometers per hour, revolutionizing travel between Mumbai and Ahmedabad.

Innovative design: The tunnel will feature a single tube with two tracks, facilitating bi-directional travel for the bullet train.

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Strategic locations: Major construction will occur at three sites: Ghansoli, Shilphata, and Vikhroli. The first TBM will start excavation in Ghansoli, heading towards Thane Creek.

Environmental protection: Building the tunnel underwater helps preserve the Flamingo Sanctuary and Mangrove Forest in Thane Creek, and also circumvents the challenges of land acquisition in densely populated Mumbai.

Prior experience: India has previously constructed underwater tunnels, such as the Kolkata Metro tunnel beneath the Hooghly River and Mumbai’s underwater metro tunnel on Line 3 beneath the Mithi River.

This ambitious project underscores India’s growing engineering prowess and commitment to advancing high-speed rail infrastructure while balancing environmental and logistical considerations.