After enduring nine days trapped underground due to severe flooding in Nepal, two workers have been successfully rescued from the Upper Trishuli 3A Hydropower Station. Sanjay Sah and Kabir Maharjan were located approximately 170 meters within the hydropower tunnel, marking a significant achievement in the ongoing rescue efforts.
Sanjay Sah, a 30-year-old mechanical foreman employed by the Nepal Electricity Authority, had chosen to remain behind in order to assist his colleagues during the flood that hit the Trishuli valley on August 26. While confined in the tunnel, Sah spent nearly a week waiting for rescue, sharing with rescuers that he had recited mantras to maintain his spirits during the ordeal.
The successful extraction of Sah and Maharjan has sparked renewed optimism for the families of other workers who are feared to be trapped within Nepal’s hydropower facilities. Authorities estimate that approximately 900 workers are currently unaccounted for across various hydropower sites, with around 500 believed to be stuck underground.
During his time underground, Sah informed Nepali Army officials that the control room typically housed only four to six personnel, yet there were about 40 to 45 individuals present when the disaster struck. He had warned his colleagues to evacuate upon realizing the flood was imminent, but he chose to stay behind. “When such a significant accident occurred, I felt it was not appropriate for me to flee,” Sah stated in a video released by Nepali authorities, as reported by Reuters.
Throughout the nine days spent in darkness, Sah maintained communication with three or four individuals in the tunnel and speculated that there may be others trapped deeper inside.
The rescue operation began amidst the challenge of a missing tunnel entrance, which had been obscured by mud, rocks, and debris due to the floods that altered the landscape surrounding the hydropower station. Arnold Dix, president of the International Tunnelling and Underground Space Association and an advisor to the rescue efforts, noted that the teams faced an unprecedented situation where they first needed to determine the location of the tunnel entrance.
Rescue teams utilized various resources, including old topographic maps, post-disaster satellite images, helicopter footage, and surface indicators like power poles, to triangulate the tunnel’s entrance and commence digging.
Locating the entrance was merely the first challenge; the tunnel had become obstructed by massive amounts of mud and rocks, with some boulders larger than vehicles. Rescue crews employed excavators to clear the debris and, in particularly difficult areas, resorted to controlled explosions to break through, a risky move given the possibility of survivors being trapped beyond the blockages.
Dix acknowledged the careful management of these blasts by the Nepal Army to ensure the stability of the tunnel and the safety of any individuals still inside.
Water accumulation posed an additional problem as rescuers advanced deeper into the tunnel, necessitating the use of pumps and the excavation of trenches to drain the flooding.
Ultimately, the rescuers managed to create a narrow passage through the debris close to the top of the original tunnel, leading to a breakthrough moment. In the early hours of Friday, they heard voices emanating from within the tunnel. Local reports indicate that they called out and received a faint reply.
Shortly thereafter, they reached Sah and Maharjan. Images released by the Nepal Army depicted one worker being carried out on a rescuer’s back, while the other was transported on a stretcher. Both individuals were airlifted to Kathmandu for medical attention, with reports indicating their vital signs were stable; however, Maharjan was unable to move his limbs, while Sah’s injuries were assessed as not life-threatening.
Despite this significant rescue, the search continues, with about 900 workers reported missing from hydropower projects in the affected area and roughly 500 believed to be trapped in tunnels, according to officials. At the Trishuli 3A site alone, the Independent Power Producers Association of Nepal estimates that around 115 workers remain trapped.
Rescue teams are also scouring other hydropower sites throughout the Trishuli valley. At Rasuwagadhi, they have managed to penetrate about 250 meters into a tunnel before encountering another blockage, with officials suggesting that numerous individuals could be trapped in a chamber where they might have access to food and water.
The rescue operation has garnered support from specialists from India, China, and South Korea, alongside local Nepali Army and police units.
Additionally, the operation has embraced modern technology. An engineers’ WhatsApp group, established prior to the disaster, has evolved into a real-time technical support network, now boasting over 500 members, including engineers and individuals familiar with the hydropower plants and their underground configurations.
When rescuers at the buried Chilime hydropower plant required specific information, a government official reached out to the group for layout diagrams. Within minutes, engineers provided detailed drawings of the powerhouse and access tunnels.
Members of the group have also shared the names and contact numbers of missing workers, hoping that telecom data could assist in pinpointing their last known locations. News agency Reuters has obtained information from the group and spoken to several individuals involved in the rescue.
Nepal Army spokesperson Raja Ram Basnet remarked that this situation is unlike any typical tunnel closure, as the terrain and structural integrity of the tunnels have been significantly altered by the flooding.
The survival of Sah and Maharjan has given the rescue teams a much-needed morale boost and proof that individuals can endure in underground conditions for extended periods after such disasters. Dix mentioned that the teams are now focusing on what he refers to as a “Goldilocks zone” to locate further survivors.
