Assam’s First Underwater Tunnel DPR Completed; ₹6,000 Crore Project Awaits Cabinet Approval.

The detailed project report (DPR) for Assam’s pioneering underwater tunnel, set to connect Numaligarh and Gohpur at an estimated cost of ₹6,000 crore, has been finalized. This greenfield infrastructure project aims to build India’s first-ever road tunnel beneath a major river, the Brahmaputra, and is expected to be presented soon for approval by the Union Cabinet.

The tunnel holds significant strategic importance, given its proximity to Arunachal Pradesh, which shares a sensitive border with China. Officials anticipate the project will take around five years to complete once construction begins.

A senior Assam government official told the Economic Times, “The DPR is ready, and shortly the project will be placed before the Union Cabinet for approval.” Due to the scale and strategic significance, final clearance will come from the Cabinet Committee on Infrastructure, headed by the Prime Minister.

The project has already secured clearance from the Standing Committee of the National Board for Wildlife (NBWL). However, the committee has requested further scientific studies on the potential impact of the tunnel on soil stability, groundwater flow, sediment dynamics, and seismic vulnerability.

The National Highways and Infrastructure Development Corporation Limited (NHIDCL) is tasked with implementing the project. The Ministry of Road Transport and Highways (MoRTH) prepared the DPR, which was technically appraised by NHIDCL’s Project Appraisal and Technical Scrutiny Committee (PATSC).

The tunnel corridor spans approximately 33.7 kilometers, including both the tunnel and connecting roads between Gohpur and Numaligarh. Notably, the tunnel crown will be situated around 32 meters below the lowest bed level of the Brahmaputra, which is known for its considerable depth in this region.

Officials highlighted that the decision to construct a tunnel beneath the Brahmaputra was driven by strategic and defense considerations, ensuring better connectivity in a border-sensitive area.

Assam Chief Minister Himanta Biswa Sarma previously shared his vision for the project, saying, “I wondered why there are several bridges over the river but no tunnel. Inspired by the Atal Tunnel in Jammu and Kashmir, I envisioned a tunnel under the Brahmaputra where trains and vehicles could move. Initially, I thought it was a dream, but discussions confirmed it’s feasible between Numaligarh and Gohpur. This project will bring the two banks of the Brahmaputra closer than ever.”

If approved, this ambitious infrastructure project will mark a transformative leap in Assam’s connectivity and defense readiness, setting a precedent for future underwater tunnels in India.