Breakthrough in Tunnel No. 4 of Dmr–Khm BG line project

The North East Frontier Railway celebrated its achievement of another milestone with the breakthrough of Tunnel no. 4 between Molvom-Pherima station that measures 1319 meters in length including 151 meters cut and cover on January 24. (Photo Courtesy: CPRO-NFR)

The North East Frontier Railway celebrated its achievement of another milestone with the breakthrough of Tunnel no. 4 between Molvom-Pherima station that measures 1319 meters in length including 151 meters cut and cover on January 24. (Photo Courtesy: CPRO-NFR)

DIMAPUR, JANUARY 25 (MExN): In another major step towards completion of Dimapur- Kohima new Broad Gauge Line connectivity project, North East Frontier Railway (NFR) recently achieveda major milestone in the second phase of the project.

Breakthrough of Tunnel no-4 between Molvom-Pherima station that measures 1319 meters in length including 151 meters cut and cover was completed on January 24.

This is the 2nd longest tunnel in phase-II of the project. This achievement is considered a major step ahead for connecting Kohima with rest of the nation through Indian Railways network, a press release issued by Chief Public Relations Officer NF Railways, Sabyasachi De informed today. 

The construction of the tunnel was started from portal – 1 side on March 10, 2021. Work from Portal – 2 started on January 23, 2023. The rock strata encountered is mainly shale and extremely weathered in nature with seepage of water present at few locations, inside the tunnel. 

To construct the tunnel, railways facednumerous problems as continuous rains since April, 2022 and extremely poor quality of soil in Tunnel no. 4 led to squeezing and sliding at portal – 2 affecting the progress, the CPRO revealed. Guidance from Geological Survey of India and independent consultant were sought to solve the problems.

The average rate of underground excavation is 41.25 meters per month. The underground excavation work is executed by using New Austrian Tunneling Method (NATM), and by deploying 210 no’s of manpower round the clock since the starting of the tunnel. With the final breakthrough of tunnel, underground excavation of 1168 meters has been completed. Final lining of the tunnel is targeted for completion in May, 2024. 

The total length of ongoing project is 82.5 km (2.75 Km in Assam and 79.75 Km in Nagaland) having 08 new stations vizDhansiri, Dhansiripar, Shokhuvi, Molvom, Pherima, Piphema, Menguzuma and Zubza. The project includes 24 major bridges, 156 minor bridges, 6 Road Over Bridges, 15 Road Under Bridges and 21 Tunnels of 31 km length. The total anticipated cost of the project is Rs. 6,663 crores.