Train to Sikkim: Railways completes mining in 10 out of 14 tunnels, sets August 2025 deadline

New Delhi: With the completion of mining work in 10 out of 14 tunnels, the Railways has set a new deadline of August 2025 to finish the Sivok-Rangpo Rail Project (SRRP) which will connect Sikkim with the rest of the country through a rail network for the first time, a senior official said on Friday.

The project, covering a total length of 44.96 km between Sivok (West Bengal) to Ranpo (Sikkim), has 14 tunnels, 22 bridges (13 major and 9 minor) and five railway stations viz Sivok, Riyang, Teesta Bazar, Melli and Rangpo.

At present, trains going towards Guwahati from other parts of the country pass through Sivok railway station which now pave the way for a new rail route to Rangpo in Sikkim via Riyang, Teesta and Melli (all in West Bengal).

"Out of the 14 tunnels, mining work has been completed in 10. Out of the 10, we have completed the lining work in four tunnels with work going on in the rest six. The longest tunnel is 5.3 km and the shortest one 538 metres," the official said.

He added, "Out of 13 major bridges, 12 are ready with the substructure. The maximum height of the pier (of Bridge-17) is 85 metre, constructing which was itself an uphill task. The most demanding aspect of the project is that 86 per cent of the total rail line passes through tunnels and five percent over bridges. Only nine percent is under the open sky."

Talking about the challenge in meeting the August 2025 deadline, he said, "We experienced significant squeezing/deformation in T-8 and T-10 due to the very poor strata of rocks. We took remedial measures to control it by cement consolidation, grouting and increased primary support as per the design," an official from Ircon International, which is constructing the whole project, said.

He added, '"To address this issue, several other corrective measures had been taken. However, progress has been slow, due to challenging rock conditions. To address this challenge, project engineers have adopted specialized support methods."

Project officials say that Teesta Bazar station, which is the country's first underground railway station, is also nearing completion with the last leg of work going on.

"We will start laying rail tracks from the end of May from Tunnel 14 which falls in Rangpo," the Ircon official said.

He added, "Despite encountering challenging geological conditions and steep terrain, the SRRP team continues to make steady progress. The disruption in communication along NH-10 from Sivok to Rangpo over the past four months due to the flash flood on River Teesta on October 4, 2023 has significantly impacted tunnel, bridge, and yard works."

Although this project was sanctioned in 2009-10, the land acquisition and forest clearances issued delayed its progress as the rail line crosses through Mahananda Wildlife Sanctuary, Kurseong forest division, Darjeeling forest division, Kalimpong forest division and the East Sikkim forest division.

The work progress of the project also suffered due to the COVID pandemic from March 2020 to September 2020 and December 2020 to Feb 2021.

Railway officials say that at present all the tenders for the tunnels, bridges and yards have been awarded and execution of the works is in progress.

"The initial cost of the project was Rs 4,085 crores (estimate 2015) but the revised cost is Rs 12,132.95 crores approximately," the Ircon official said.