The making of Atal Tunnel under the Rohtang Pass

Atal Tunnel, Rohtang has been constructed below the formidable Rohtang Pass, on the Manali Leh Highway, that remained closed for six months every year due to the pass being covered by heavy snow. The Tunnel connects Manali to Lahaul Valley throughout the year and reduces the road length of Manali - Leh road by 46 Kms. With a length of 9.02 Km, this is the longest tunnel in the world to have been constructed above an altitude of 10,000 feet. The construction has involved the excavation of 12 lac cum, use of over 12000 tons of steel, over 1,00,000 tons of concrete, and 1.7 lac tons of cement.

Many unique technical challenges, such as high overburden, unpredictable and varying geology, excessive snowfall were faced during construction. However, the biggest one among them was the most treacherous shear zone ever seen in tunneling, where over 8,000 liters of water per minute gushed into the tunnel creating major construction hurdles. These and many other unique features and challenges of this engineering marvel will be presented.

About the Speaker:
Lt Gen Harpal Singh is an alumnus of the National Defence Academy, Khadakwasla. He was commissioned into the Corps of Engineers of the Indian Army in December 1982. He is a graduate of Defence Services Staff College, Higher Defence Management Course, and National Defence College. His academic achievements include a double M. Tech from Virginia Tech (USA), Masters in Management Studies (Osmania University), and M. Phil (Madras University). He held many critical command appointments including command of Border Roads Task Force in the J&K valley, Chief Engineer of Project Dantak (BRO) in Bhutan, Chief Engineer (Navy), Mumbai, and Chief Engineer Eastern Command, Kolkata. He also held many prestigious staff appointments including Deputy Military Secretary at Central Command, Directing Staff at the College of Defence Management, Secunderabad, Additional Military Secretary, and Director General of Military Training at Army HQ. He is credited with the resurgence of the Border Roads Organisation as its Director-General during 2018 – 2020.