Rishikesh–Karnaprayag rail line to have 16 tunnels: How India’s homegrown technology is advancing Himalayan connectivity

The development comes amid fresh Chinese restrictions on TBM exports, highlighting the importance of domestic manufacturing for infrastructure projects that require specialised tunnelling equipment, according to The Economic Times.The push forms part of a broader effort to develop domestic capabilities spanning the design, manufacturing and maintenance of equipment used in railway, highway, metro and power infrastructure projects.

India had previously relied on imported TBMs for major tunnelling work.Rishikesh–Karnaprayag railway line: An engineering challengeThe 125-km Rishikesh–Karnaprayag railway project in Uttarakhand illustrates why advanced tunnelling technology is critical to India's infrastructure expansion. The route includes 16 main tunnels and 19 bridges, with approximately 83% of the alignment passing underground.Describing the project on X, Vaishnaw said, “Engineering through the Himalayas! 125 km, 12 stations, 83% tunnels.

The Rishikesh-Karnaprayag rail line is not just a track, it's Uttarakhand's lifeline to the future.”Construction through the Himalayan region presents specific geological challenges. In parts of the Young Fold Mountains, softer ground can squeeze inward after excavation, complicating tunnel construction.Vaishnaw said engineers modified the TBMs used for the project to address these conditions. The changes included adjustments to the cutter head and shield, along with a drive system designed to deliver additional torque and thrust.India’s push to reduce dependence on imported technologyThe development of larger domestically manufactured TBMs could support India's expanding pipeline of underground infrastructure projects.

These machines are used to excavate tunnels through soil and rock while supporting the surrounding ground, making their design and capabilities important for projects involving complex terrain.Vaishnaw said, “There was a time when all tunnel boring machines had to be imported.”“But now, all 8-meter diameter tunnel boring machines are being manufactured in India. Moreover, even 15-meter diameter tunnel boring machines have now started being made in India.

There is a TBM plant in Tamil Nadu. And very soon, TBMs with a diameter exceeding 16 meters will also be manufactured in India. This means India is becoming self-reliant (Aatmanirbhar) in TBMs—right from design and manufacturing to maintenance,” the minister added.Better connectivity for UttarakhandOnce completed, the Rishikesh–Karnaprayag railway line is expected to improve rail connectivity across Uttarakhand and facilitate access to destinations including Karnaprayag, Rudraprayag, Kedarnath and Badrinath.

The project also has strategic significance, with Karnaprayag located around 123 km from the India–China border, according to Vaishnaw.The railway project and the domestic TBM manufacturing push reflect two connected aspects of India's infrastructure growth: building transport links through difficult terrain while developing more of the specialised technology needed to execute such projects.