Incident Details
An unfortunate incident occurred at 1:04 P.M. on July 20, 2026, inside the under-construction Head Race Tunnel (HRT) of the NHPC Teesta Stage VI Hydroelectric Project (500 MW), located in Samardung, South Sikkim. The incident was caused by a sudden burst of suspected methane gas that was trapped or embedded inside the rocks, which led to an explosion. The explosion generated dense fumes and toxic gases.
Response and Rescue Operations
The project team immediately activated its emergency response protocols. Operations are being conducted in close coordination with the district administration, National Disaster Response Force (NDRF), State Disaster Response Force (SDRF), and other local authorities and emergency agencies. A special rescue team from DG Mines Safety has also reached the site. NHPC's site engineering teams are working round-the-clock alongside the authorities to assist in stabilizing the tunnel environment and ensuring rescue. NHPC's Top Management has reached the site and is closely coordinating with all teams.
Human Impact
As per the latest information from the site, 25 personnel were trapped inside the tunnel following the incident. Out of these, 10 casualties have been reported so far. All possible efforts are being made for the evacuation of the remaining trapped personnel.
Investigation and Forward Actions
A detailed investigation will be undertaken to ascertain the exact cause of the incident. NHPC states it remains committed and is extending full support to the rescue agencies and the affected families.