Work on the long-delayed strategic all-weather Atal Rohtang Tunnel that will connect Manali to Lahaul and Spiti valley in Himachal Pradesh throughout the year has been completed and will be ready for inauguration in two weeks, officials aware of the development said.
The tunnel is scheduled to be inaugurated by Prime Minister Narendra Modi in September.
The strategic tunnel which is nearing completion, is a step in the direction of providing all weather connectivity to remote border areas of Himachal Pradesh and Ladakh, which otherwise remained cut off from the rest of the country for about six months during winters. The tunnel is also significant from a military logistics point of view and will provide better connectivity to the armed forces in reaching Ladakh.
On completion, it is set to become the world’s longest road tunnel at an altitude above 3,000 metres.
The Rohtang Tunnel is being constructed in the Pir Panjal ranges of Himachal Pradesh, since the Manali-Sarchu-Leh road remains closed for nearly six months in a year due to the Rohtang Pass being completely snow clad between November and April. Upon completion, the all-weather tunnel will connect Manali to Lahaul and Spiti valley throughout the year and will reduce the road length of the Manali-Rohtang Pass-Sarchu-Leh road by 46 km.
The Rohtang Tunnel was rechristened Atal Tunnel by the Union Cabinet chaired by Prime Minister Narendra Modi in December last year. The decision to construct a strategic tunnel below the Rohtang Pass was taken by former Prime Minister Atal Bihari Vajpayee in 2000.
In 2002, Prime Minister Atal Bihari Vajpayee declared the construction of Rohtang Tunnel and laid the foundation of the approach road to the tunnel. The Border Roads Organisation (BRO) engaged RITES in March 2002 to undertake feasibility studies.
The 8.8-kilometre long tunnel is the world’s longest tunnel above an altitude of 3,000 metres. It will reduce the distance between Manali and Leh by 46 kilometres and reduce travel time by 4.5 hours.
It is a 10.5-metre wide single tube bi-lane tunnel with a fire proof emergency ‘escape tunnel’ built into the main tunnel itself.
On September 24, 2009, a contract was awarded to Strabag-Afcons Joint Venture (SAJV) for the tunnel’s construction. Construction for the project finally began in 2010, in the presence of then UPA chairperson Sonia Gandhi.
The long-delayed tunnel has, however, gone through tough challenges for construction owing to the geographical location and difficult topographic profile of the region. The delays to due tough weather conditions also escalated the cost of the project from Rs 1,458 crore to around Rs 2,500 crore.
“The Atal Rohtang Tunnel will be ready for inauguration purpose in the next two weeks…It has been the most challenging project in terms of construction due to geographic conditions, weather and multiple hazards faced during the construction. We have faced multiple avalanches. In 2013, the tunnel collapsed at the north portal. In 2014, we had to evacuate the site in a hurry due to sudden harsh weather conditions… Army helicopters have had to be used to rescue nearly 100-150 workers. Full credit goes to Strabag-Afcons and the Border Road Organisation for their strict safety regulations and hawk-like vigil in the tunnel construction that was able to ensure the tunnel was constructed without any fatality in the project,” Satish Paretkar, Director, Hydro and Underground division, Afcons said.
Since there were multiple avalanche zones at both the portals the workforce were also given GPS trackers that could track their location and send a signal to the control room in case anyone was stuck or hit by any avalanche.
The Border Roads Organisation (BRO) and the contractors had to deal with major geological, terrain and weather challenges that included the most difficult stretch of the 587-metre Seri Nalah Fault Zone. The so-called breakthrough from both ends was achieved on October 15, 2017.
“The biggest challenge we faced was due to the Seri Nalla Zone that took us almost four years to excavate 041 km of the zone. At the Seri Nalla Zone in the south portal, we dealt with constant collapse of the tunnel’s face. The zone threw up extremely fractured and pulverized rock and very poor geological conditions. We experienced huge water ingress of up to 127 litres per second. When you have so much water from a top glacier lake it becomes impossible to continue. We could not trace the glacier’s source, and had we not found the solution Rohtang would not have been possible,” he added.