Tunnel Vision!

Chenani Nashri is slated to be India’s first tunnel with a world-class integrated tunnel control system (ITCS), where ventilation, fire control, signals, communication and electrical systems are automatically activated.

Safety has been the paramount consideration for India’s longest tunnel. Now at 9 km – reducing the journey by 31 km – the recently completed Chenani-Nashri Tunnel serves as an all-weather connection between the Kashmir Valley and Jammu. The road to completion had its share of rough patches, though. For starters, working in immature rocks and geological uncertainty in the Himalayan terrain posed a huge challenge in itself. For SC Mittal, Chief Executive, IL&FS Transportation Networks, another significant challenge was to secure forest approval from the Forestry Advisory Committee in J&K. Adding to this was the constraint of disposing off the debris generated during the excavation process. Nevertheless, after five years and nine months, the project was completed successfully.

The specs 

The finished diameter of the horseshoe-shaped main tunnel is 11.75 m, which includes a carriageway width of 9.35 m + 1.2 m width of cable trench on either side of the main tunnel. The main tunnel comprises a bi-directional two lane. The escape tunnel is D-shaped with a clear carriageway width of 5 m; it is a pressurised tunnel with a super atmospheric pressure of 50 pa to avoid ingress of smoke during a fire emergency in the main tunnel, thus making it a safe passage for users.