Kathmandu: Four excavators have been deployed to accelerate efforts to open an access route into the tunnel at the Upper Trishuli-3 ‘A’ Hydropower Project, where people are believed to be trapped inside underground structures. According to the Nepal Electricity Authority (NEA), drilling and excavation work is continuing to create a passage for rescuers to enter the tunnel.
According to the NEA’s situation update as of 3 p.m. on September 1, 2026, rescue operations are continuing without interruption. Four excavators are being used for drilling and excavation to prepare the necessary access route for rescuers.
Consultations with Experts Involved in Powerhouse Construction
The NEA said the rescue operation is being advanced based on an action plan prepared after consultations with experts who were directly involved in the construction of the powerhouse.
Earlier, experts studying the maps of the project’s underground structures had suggested exploring alternative rescue options by utilizing various access structures already available at the project.
In particular, Engineer Lilnath Bhattarai, former CEO of Chilime Hydropower and former deputy executive director of the NEA, has suggested studying the as-built drawings included in the project completion report. Such drawings show the structures as they were actually constructed and could help identify potentially shorter routes to reach those trapped inside.
Water and Debris Being Removed Through Excavation
According to the NEA, excavation work is currently underway, along with dewatering—the removal of accumulated water—and the clearance of debris, including rocks, soil and rubble.
The effort is aimed at creating conditions that will allow rescuers to safely enter the tunnel.
Earlier, rescue teams had also begun work to open an access route toward the powerhouse, remove water and clear obstructions. In the latest phase, the rescue team was reported to have reached the entrance of the cable duct tunnel.
Water and Mud Remain Major Challenges
One of the biggest challenges in the rescue operation at Trishuli-3 ‘A’ is removing the water, mud and debris accumulated inside the tunnel and creating a safe access route.
Recent details from the Nepal Army also stated that rescuers had located the tunnel head and were using compressors to send air inside while pumping out water. Efforts to open an alternative route are also continuing.
The rescue teams are also using rock breakers and heavy equipment to create an entry point into the tunnel.
Technical Expertise Being Used in Rescue Efforts
The NEA’s decision to consult experts directly involved in the powerhouse construction indicates that technical knowledge from the project’s construction period and detailed information about its underground structures are now being utilized in the rescue operation.
Because underground structures in hydropower projects are complex, the experience of engineers and technicians involved in construction can be valuable in determining where individual tunnels lead, which structures could provide alternative access, and how water and debris can be removed.
All Rescue Options Need to Be Pursued in Parallel
Alongside efforts to open the main access route at Trishuli-3 ‘A’, teams are simultaneously working on dewatering, debris removal, drilling and identifying alternative access routes.
Experts had previously recommended studying the project’s various underground structures, access tunnels and other potential routes to identify the shortest possible path to those trapped inside.
The current situation also highlights the need to accelerate rescue efforts by testing all available technical options rather than relying on a single access route.
Search and rescue operations for people trapped inside underground structures of various hydropower projects have continued following floods in the Bhotekoshi-Trishuli corridor. Teams have been mobilized at Trishuli-3 ‘A’, Chilime, Langtang, Upper Trishuli-1 and Trishuli-3 ‘B’, among other projects.
At Trishuli-3 ‘A’, the priority is clear: to create a safe route for rescuers to enter the tunnel, remove accumulated water and debris, and make maximum use of available technical expertise and equipment to reach those trapped inside as quickly as possible.
Jalasrokar
