Gohpur Numaligarh Tunnel: India's first underwater road-cum-rail tunnel under Brahmaputra approved - Check cost, connectivity & more

Gohpur Numaligarh Tunnel Project: Union Cabinet has approved the construction of a four-lane, access-controlled greenfield corridor from Gohpur (NH-15) to Numaligarh (NH-715). This includes a 15.79-km-long road-cum-rail underwater tunnel under the Brahmaputra. The total capital cost is Rs 18,662 crore. The project will have a total length of approximately 33.7 km and will be implemented under the Engineering, Procurement, and Construction (EPC) mode. The project is expected to be India's first underwater road-cum-rail tunnel and the world's second, and aims to strengthen connectivity in Assam and the wider Northeast region.

Currently, the journey between Numaligarh and Gohpur via the existing Kaliabhomora Bridge route is approximately 240 km and takes approximately six hours, passing through areas such as Kaziranga National Park and Biswanath Town.

The new greenfield corridor with tunnels aims to significantly improve connectivity in Assam, Arunachal Pradesh, Nagaland, and other northeastern states, reducing logistics costs and improving freight efficiency.

Seamless connectivity through integrated transport networks

This corridor will integrate with two major national highways—NH-15 and NH-715—and two railway sections:

Rangia–Mukongselek railway section (Gohpur side)

Furkating–Mariani loop line (Numaligarh side)

This project addresses chronic connectivity challenges in the Brahmaputra valley, where seasonal flooding and limited crossings disrupt movement. It integrates with major highways (NH-15 and NH-715) and railway lines (Rangia-Mukongselek and Furkating-Mariani sections), enabling seamless multimodal transport.

The project will also enhance multimodal connectivity by linking:

It will also improve access to four major railway stations, two airports and two inland waterway terminals, enabling faster movement of goods and passengers.

The government stated that the project will play a key role in enhancing strategic connectivity, regional economic growth, and trade, as well as strengthening links between major economic centers. The project is expected to generate approximately 8 million person-days of direct and indirect employment, supporting economic activity and development in the surrounding areas.

The tunnel section will include a twin-tube TBM tunnel with rail in one tube—15.79 km long, a road cut-and-cover section (1.26 km), and a rail cut-and-cover section (4 km). The project will connect special economic zones, industrial areas, social districts, tourist hubs including Kaziranga National Park, and major urban centers including Numaligarh, Tezpur, Gohpur, Dibrugarh, and Itanagar.