NHSRCL Completes 5km Excavation on Mumbai-Ahmedabad Bullet Train Tunnel

National High Speed Rail Corporation has completed 5km of tunnel excavation on the Mumbai-Ahmedabad bullet train corridor and begun installing critical systems inside the 21km underground section between Bandra Kurla Complex and Shilphata.

This progress marks a technical turning point for India's first high-speed rail project. The shift from excavation to systems installation demonstrates the project has overcome the most challenging underground construction phase. The 21km tunnel represents the longest continuous underground section on the 508km corridor, requiring specialized boring techniques and waterproofing in Mumbai's challenging geological conditions.

NHSRCL has not disclosed specific timelines for completing the remaining 16km of excavation or the systems installation phase. The tunnel will accommodate trains operating at 320km/h, requiring advanced ventilation, fire safety, and emergency access systems. Japanese contractors are leading the construction using tunnel boring machines designed for Mumbai's mixed soil and rock conditions. The underground section will include stations at Bandra Kurla Complex and Thane, both requiring complex integration with existing transport networks.

The Mumbai-Ahmedabad project faces mounting cost pressures, with estimates rising from the original ₹1.08 trillion to over ₹1.4 trillion. Construction delays have pushed the completion target from 2023 to 2028. The tunnel progress provides a benchmark for similar high-speed rail projects planned across India, including the Delhi-Varanasi and Chennai-Mysuru corridors, all requiring extensive tunneling through urban areas.