22 July 2026

Teesta VI Hydroelectric Project tunnel gas leak tragedy

This incident serves as a notable case study for industrial and tunneling disasters under GS3 Disaster Management, highlighting safety protocols in underground infrastructure projects.

• At least 20 workers were killed and five trapped inside an under-construction head race tunnel at Samardung in Namchi district, Sikkim, following a toxic gas leak.
• The incident occurred at the Teesta State-VI Hydroelectric Project, which is under the National Hydroelectric Power Corporation (NHPC).
• The cause of the tragedy was identified as a sudden explosive release of suspected methane gas trapped/embedded inside rock formations, generating dense smoke and toxic fumes.
• Rescue operations were conducted by site engineering teams from NHPC, local administration, and a special rescue team from the Director-General of Mines Safety (DGMS), with efforts partially hindered by rainfall.
• The Sikkim State Government announced the constitution of a high-level inquiry committee to investigate the cause of the incident along with ex-gratia assistance for affected families.

1. Underground tunneling and hydroelectric infrastructure development in the geologically fragile Himalayan region present unique industrial hazards and disaster risks. Examine the safety challenges associated with such projects and discuss the policy and technological measures required to strengthen disaster response and worker safety standards. 250 words

1. The Teesta VI Hydroelectric Project, where a major tunnel gas leak tragedy occurred, is situated in which state?
   1. Uttarakhand
   2. Sikkim
   3. Arunachal Pradesh
   4. Himachal Pradesh
   Answer B
2. Which specialized body deployed a rescue team to coordinate rescue operations during the Teesta VI hydroelectric project tunnel accident?
   1. Director-General of Mines Safety
   2. Central Mine Planning and Design Institute
   3. National Disaster Response Force
   4. Geological Survey of India
   Answer A

• Disaster and disaster management GS3

• Disaster Management
• Industry & Infrastructure

• Toxic gas kills 20 in Sikkim tunnel, efforts on to save 5 workers
• Toxic gas leak: 20 dead, efforts on to rescue 5