Chamoli Tunnel Collapse: Seven workers have died while three others remain missing after water and debris entered an under-construction tunnel of the Tehri Hydro Development Corporation Limited (THDC)
at Pipalkoti in Uttarakhand’s Chamoli district.
A total of 28 people were inside the tunnel when the accident occurred. So far, 18 people have been rescued safely, while seven have been confirmed dead. Search operations for the three missing workers is still underway on Friday.
The incident has once again highlighted the risks faced by workers involved in large infrastructure projects in India’s mountainous regions.
Sikkim Tunnel Tragedy (July 2026): One of the deadliest recent tunnel disasters occurred in July this year at the under-construction Teesta Stage-VI Hydroelectric Project in Sikkim’s Namchi district.
On July 20, a pocket of methane gas trapped in the rock strata reportedly burst inside the seven-kilometre-long head race tunnel (HRT) of the project. A total of 25 people, including project officials and workers, were trapped inside the ADIT-3 tunnel when it suddenly collapsed. 22 people lost their lives in the accident.
As part of the Teesta Stage-VI Hydroelectric Project, the tunnel is being constructed to channel high-pressure water from the reservoir to the powerhouse.
Srisailam Left Bank Canal Tunnel, Telangana (February 2025): A section of the under-construction tunnel in Nagarkurnool collapsed after water seepage. Eight workers were trapped around 14 km inside the tunnel.
The collapse took place during excavation work using a tunnel boring machine (TBM), trapping the workers for three days and counting.
Silkyara-Barkot Tunnel, Uttarakhand (November 2023): A portion of the under-construction tunnel in Uttarkashi collapsed, trapping 41 workers for 17 days. All 41 were eventually rescued in one of India’s most closely watched tunnel rescue operations.
The intense rescue mission — clocking more than 400 hours, delayed by a series of snags and overshadowed by equal parts hope and despair — ended in success for everyone involved. On the last day, rescuers broke through the last stretch of the rubble around 7 pm using the rat-hole mining technique.
Khooni Nallah Tunnel, Ramban, Jammu & Kashmir (May 2022): An adit portal of a tunnel on the Ramban-Banihal section of NH-44 collapsed following a landslide, killing 10 labourers. The government subsequently constituted an expert committee, and action was taken against the contractor.
