Pakal Dul project achieves HRT-I tunnel breakthrough
The 1000 MW Pakal Dul Hydroelectric Project in Jammu & Kashmir achieved a major construction milestone on June 10, 2026, with Tunnel Boring Machine (TBM)-1 “Marsu” completing the first breakthrough of Head Race Tunnel-I (HRT-I). The project is being developed on the Marusudar river in Kishtwar district by Chenab Valley Power Projects Private Limited (CVPPL) at an investment of Rs 126.69 billion.
Tunnel specifications
The circular HRT-I has a diameter of 7.2 metres and extends approximately 7.35 kilometres underground. The completed section passes beneath an overburden of around 2,000 metres.
The Double Shield Hard Rock TBM used for excavation is equipped with an 8.33-metre-diameter cutter head weighing 180 metric tonnes. Its shield system and probe drill unit weigh around 760 metric tonnes and extend over 17 metres. Including bridges and backup gantries, the machine has a total length of 147 metres and weighs more than 1,500 metric tonnes.
Excavation progress
TBM-1 commenced excavation on January 23, 2024, after completion of a 534-metre-long adit tunnel constructed between July 29, 2023, and January 23, 2024. The breakthrough was achieved in 29 months.
During excavation, the TBM recorded a maximum daily advance of 37.1 metres on March 10, 2025. The highest monthly progress achieved was 491 metres in July 2025.
Major sections of the two head race tunnels between Dool and Drangdhuran are being excavated using TBMs deployed by Larsen & Toubro Limited (L&T). A smaller section has been executed using the drill-and-blast method by M/s JP Associates.
Ownership structure
CVPPL is a joint venture between NHPC Limited, which holds 51% equity, and Jammu & Kashmir State Power Development Corporation (JKSPDC), which holds 49% equity. NHPC is a Navratna enterprise of the Government of India, while JKSPDC is a public sector enterprise of the Government of Jammu & Kashmir.
