BRO: Overcoming Challenges of Tunnelling in the Himalayan Region
Lt Gen Raghu Srinivasan, Director General, Border Roads Organization, discusses the unique challenges of tunnelling in the fragile Himalayan terrain and showcases success stories like the Atal Tunnel and the Sela Tunnel, highlighting the government's role in promoting tunnelling advancements.
The first challenge in tunnelling in India is dealing with the fragile geology of the Himalayas. These seismically active mountains are composed of fractured rock masses. As we undertake tunnelling projects, we must address these geological challenges carefully. The second challenge is managing water ingress, as melting snow and the porous nature of the overburden can lead to significant water flow into tunnels. Thirdly, we must ensure that our tunnelling activities do not trigger avalanches or landslides in these ecologically and geologically sensitive zones.
Our tunnelling efforts have surged thanks to government policies, direction, and funding. This support has fostered transformation and attracted investment. As a result, the bridge and tunnel sector, including border roads, has seen significant progress. Over the past decade, border roads have undergone a sea change, and our organization (BRO) has become a preferred agency for challenging border areas with both climate and geographical difficulties.
One of our flagship projects is the Atal Tunnel conceived by former Prime Minister Atal Bihari Vajpayee with the foundation stone laid in 2010. We faced numerous challenges, notably the Seri Nalla Fault Zone, where a large water channel flowed into the tunnel between kilometers 2.2 and 2.8. We managed this by using drainage reinforcement and support techniques, achieving a breakthrough in 2017. The tunnel was inaugurated by Prime Minister Narendra Modi in 2020. It is now one of the highest tunnels in the world, exceeding 10,000 feet in altitude, and holds a Guinness World Record for its length.
We have also recently completed the Sela Tunnel, connecting Tawang over the Sela Pass. Inaugurated by the Prime Minister on March 9, 2024, this tunnel faced its own challenges, including a large cavity of approximately 25x12 meters. We resolved this by isolating the cavity and working from both ends, allowing normal excavation to continue. It also posed additional challenges such as limited working seasons, long communication lines, and sub-zero temperatures. Situated at 13,000 feet, it is currently the highest in India.
Given the fragile and geologically sensitive environment, thorough investigation, exploration, specialized geotechnical analysis, and robust monitoring systems are essential. We currently have six tunnel projects underway. The Shinkun La Tunnel, recently inaugurated by the Prime Minister, will connect Himachal Pradesh to the Ladakh Valley of Padam, providing all-weather connectivity to Leh and opening access to the Zanskar region. Once completed in four years, it will be the highest tunnel in the world, situated above 15,000 feet.
In addition to tunnels, we are constructing caverns for military storage. We are building approximately 50 caverns in Leh and Ladakh, each around 75 meters in length.
To enhance our work, we have invested in both training and equipment. We have procured tunnel equipment such as boom drills, jumbo machines, heavy-duty wheel loaders, and dual-use excavators. Our training programs include on-the-job training, regular courses at our headquarters in Narayana, and a two-week tunnelling-specific course at the Maharashtra Institute of Technology in Pune for new officers. The government has also authorized us to send two officers annually for an M.Tech course at Graz University in Austria, where 12 officers have been trained so far.
The opportunities for tunnelling in India are vast. We need to continually develop our skills, as tunnels offer significant advantages, including all-weather connectivity, reduced distances, and access through challenging geological and climatic conditions.
One comment
-
The BRO is on large projects. Their experience and training can further be shared at engineering colleges and equipment manufacturing units
