NHPC Reports Accident at Teesta Stage VI Hydroelectric Project; Rescue Operations Continue

NHPC Limited has informed the stock exchanges about a tragic accident at its 500 MW Teesta Stage VI Hydroelectric Project in Samardung, South Sikkim, following a sudden explosion inside the project’s Head Race Tunnel (HRT) on July 20, 2026.

According to the company’s official disclosure, the incident occurred at approximately 1:04 PM and resulted in multiple casualties. Rescue operations are currently underway with the support of several government agencies.

Explosion Triggered by Suspected Methane Gas

NHPC stated that the explosion was believed to have been caused by a sudden burst of suspected methane gas trapped within the rock formations inside the tunnel.

The blast generated dense fumes and toxic gases, creating extremely hazardous conditions for personnel working inside the tunnel.

As per the company’s initial update:

• Around 25 personnel were trapped inside the Head Race Tunnel.
• 10 fatalities have been confirmed so far.
• Rescue operations are continuing to locate and evacuate the remaining trapped workers.

The company noted that these figures are based on preliminary information and may be updated as rescue efforts progress.

Rescue Operations in Full Swing

Immediately after the incident, NHPC activated its emergency response plan and began rescue operations in coordination with multiple agencies, including:

• National Disaster Response Force (NDRF)
• State Disaster Response Force (SDRF)
• District Administration
• Local authorities
• Directorate General of Mines Safety (DGMS) rescue team

NHPC’s senior management has also reached the project site to oversee rescue efforts and coordinate with government authorities.

The company stated that every possible effort is being made to safely evacuate the remaining personnel.

Investigation to Determine Cause

NHPC has announced that a detailed investigation will be conducted to determine the exact cause of the incident.

The company has also assured full cooperation with regulatory authorities and emergency response agencies while extending all possible support to the affected workers and their families.

Potential Project Impact

At this stage, NHPC has not disclosed any financial impact arising from the accident.

However, incidents of this nature could potentially lead to:

• Temporary disruption in construction activities.
• Delays in project execution timelines.
• Higher costs related to safety enhancements and investigations.
• Compensation and rehabilitation expenses.
• Additional regulatory reviews before work resumes.

The actual impact on the project’s schedule and financials will become clearer once investigations are completed.