A major accident at the under-construction Teesta Stage-VI Hydroelectric Project in Sikkim’s Namchi district has claimed multiple lives after a suspected methane gas explosion and tunnel collapse trapped workers undergroundAt least 20 casualties have been reported so far after a section of the under-construction Head Race Tunnel (HRT) of the National Hydroelectric Power Corporation Limited Teesta Stage-VI Hydroelectric Project collapsed yesterday at Samardung in Namchi district in Sikkim.
According to officials, the incident occurred on Monday at the tunnel construction site in Samardung village. Initial reports indicate that a buildup of methane gas triggered an explosion, leading to the collapse of a section of the tunnel. Rescue teams from the National Disaster Response Force (NDRF), state agencies, and project personnel were immediately deployed.
Rescue efforts have been severely hampered by the presence of toxic gases, including methane, carbon monoxide, and hydrogen sulphide, forcing responders to work in short, oxygen-assisted shifts. Authorities have confirmed fatalities, while several workers remain trapped as search operations continue.
NHPC, which is executing the 500-MW Teesta Stage-VI Hydroelectric Project, said its senior management is at the site overseeing rescue and relief operations. The company stated that every effort is being made to safely evacuate those still inside the tunnel.
Sikkim Chief Minister Prem Singh Tamang visited the site and reviewed the rescue operations. Officials said the exact cause of the explosion will be established after a detailed investigation, though preliminary assessments point to a sudden methane gas accumulation inside the tunnel.
The tragedy has once again highlighted the engineering and geological challenges associated with infrastructure projects in the fragile Himalayan region, where unstable rock formations, landslides, and underground gas pockets pose significant risks to construction activities.
West Bengal Governor RN Ravi expressed anguish over the loss of lives in the Namchi tunnel collapse, extending his deepest condolences to the bereaved families and wishing a speedy recovery to the injured. “Deeply saddened by the tragic loss of precious lives in the tunnel collapse in Namchi, Sikkim. My heartfelt condolences to the bereaved families. I pray for the speedy rescue and safe evacuation of those still trapped and the swift recovery of the injured.”
Rescue operations are ongoing, and authorities have said the casualty figures may change as more information becomes available.NHPC has said that a detailed investigation will be undertaken to ascertain the cause of the incident.
(Image courtesy: AIR)

