Himachal Pradesh’s Engineering Marvel: Longest Tunnel Built Successfully

Kullu District, Himachal Pradesh, has witnessed the completion of an engineering marvel. After an ambitious project spanning 23 years, the construction of the Parvati Hydroelectric Project’s Phase 2 (PHEP) involved the successful excavation of a 32 km-long headrace tunnel using a foreign-made Tunnel Boring Machine (TBM). The tunneling process is almost complete, with the TBM set to be extracted from underground, a month-long operation.

The tunnel excavation began from the Pulga Dam in Manikaran Valley and reached Sainj Dam. The management of the project claims that this feat of creating the world’s longest tunnel using a TBM has now been achieved. The TBM, which cost Rs. 200 crores, is considered one of the most advanced machines globally. It can cut through mountainous terrain at a rate of 800 to 900 meters per month. An interesting feature of this TBM is its ability to advance from one end of the mountain to the other, emerging on the opposite side, making it impossible to retrieve the machine in between. The 32 km-long tunnel project presented many challenges, taking a considerable amount of time and involving numerous difficulties. The total cost of constructing the tunnel amounted to Rs. 2000 crores.

This engineering marvel serves as a prime example of excellence in the field of engineering in Kullu District, Himachal Pradesh. Nirmal Singh, the Director of the PHEP project, highlighted the difficulties encountered during the excavation process, especially in the steep and challenging terrains of the region. However, the successful completion of this remarkable tunnel is a significant achievement.