Indian Railways is set to achieve a major engineering milestone by constructing the country first floating rail tunnel junction. This unique structure is being developed as part of the 126 km long Rishikesh-Karanprayag railway project in Uttarakhand. The junction is specifically designed to handle the challenges of weak soil and high seismic activity found in the Himalayan region.
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How does the floating rail tunnel junction work?
The junction is being built in the Byasi-Devprayag section where the ground consists of weak soil and sandy material instead of solid rock. Engineers are using double-arch seismic isolation technology for the first time in India. This allows the tunnel to act as a shock absorber during earthquakes. Instead of cracking or collapsing under pressure, the structure can shift slightly and then return to its original position. This design ensures the long-term safety of the tracks and the trains passing through this sensitive zone.
Key project timelines and construction schedule
Rail Vikas Nigam Limited is managing the construction of this 126 km railway line. The project is moving ahead with specific deadlines for different phases of development. The construction of the 14.57 km long Tunnel Number 8 already began in April 2025. Other major milestones are listed below:
| Activity or Station Work | Scheduled Start Date |
|---|---|
| Rail Track Laying Process | May 2026 |
| Electrical and Signaling Work | October 2026 |
| Devprayag and Srinagar Stations | May 2026 |
| Gauchar and Karanprayag Stations | May 2026 |
| Final Project Completion | December 2028 |
RVNL officials stated that the project is a transformative lifeline for the Himalayan region. While the terrain is difficult, the use of advanced global engineering standards will help complete the project by the December 2028 deadline. Multiple stations including Dhari Devi and Tilani will also see construction starting in early 2026.

























