RVNL Achieves Historic TBM Breakthrough in India's Longest Rail Tunnel
Rail Vikas Nigam Limited (RVNL) has achieved the first TBM breakthrough of Tunnel-8, the longest transportation railway tunnel in India, as part of the ambitious 125-km Rishikesh–Karnaprayag Broad Gauge Rail Link Project in Uttarakhand. The breakthrough was achieved in presence of Hon’ble Railway Minister Ashwini Vaishnaw, who visited the site to mark this momentous milestone in Himalayan rail connectivity. His visit was truly inspirational for all the workers and officials who worked tirelessly to achieve this milestone.
The 14.57-km tunnel was bored using a state-of-the-art Tunnel Boring Machine (TBM) named Shakti, marking a historic moment in Indian tunneling history. This is the first time TBM technology has been deployed for rail tunneling in mountainous regions of the country, and the progress sets a new global benchmark with a 9.11-meter diameter single-shield rock TBM.
On this occasion, Pradeep Gaur, Chairman & Managing Director, RVNL said, “This breakthrough marks a significant step in the Government’s mission to enhance connectivity across India’s hill states. More than just a technical milestone, it showcases RVNL’s technical prowess, determination and risk averseness to execute complex infrastructure projects in some of the most challenging terrains. With this achievement, Shakti hasn’t just cut through rock it has paved the way for a more connected and resilient Uttarakhand.”
The Rishikesh–Karnaprayag project, executed from concept to commissioning by RVNL, aims to transform regional connectivity by linking key towns such as Devprayag, Srinagar, Rudraprayag, Gauchar, and Karnaprayag across five Himalayan districts. More than 83% of the 125 -km alignment passes through tunnels, involving over 213 km of tunneling across main and escape routes.
Tunnel-8, twin tunnels located between Devprayag and Janasu stations, are being excavated with two TBMs Shakti and Shiva, each with a boring diameter of 9.11 meters and equipped with advanced support systems. The second TBM, Shiva, is expected to achieve breakthrough by July 2025.
The TBM has faced extraordinary logistical and geological challenges, including transporting 165 MT components from Mundra port to site across narrow Himalayan roads and old bridges. The tunnel also lies in tectonically active Seismic Zone IV, requiring sophisticated design and continuous advance geological probing.
Once complete, the project will drastically reduce travel time, improve all-weather access to remote regions, and boost tourism and economic development across Uttarakhand. It is also a critical step in realizing the Char Dham rail connectivity initiative.
With this achievement, RVNL continues to reinforce its position as a premier infrastructure executor, pioneering modern construction methods in India’s most complex terrains.
