Major Milestone Achieved: Tanahun Hydropower Project’s main tunnel breakthrough

KATHMANDU: In a significant development for Nepal’s energy landscape, the Tanahun hydropower project has achieved a major breakthrough with the completion of its main tunnel.

This tunnel, integral to the project’s infrastructure, boasts a reservoir with a capacity of 140 megawatts, harnessing the waters of the Seti River flowing through the border of Tanahun’s Rishing Rural Municipality-1 and Byas Municipality-5.

The breakthrough moment was marked by a ceremony where Energy, Water Resources, and Irrigation Secretary Gopal Prasad Sigdel and Executive Director of Nepal Electricity Authority and Tanahun Hydropower Board Chairman Kulman Ghising jointly initiated the final phase. Under the project’s package-2, a 1,493-meter-long tunnel, from the reservoir mouth to the penstock pipe, has successfully been completed.

With a diameter of 7.4 meters, the main tunnel will soon undergo concrete lining. Once operational, it will channel water to generate electricity through a 213-meter-long penstock pipe in an underground power plant.

During the ceremony, Secretary Sigdel expressed satisfaction with the project’s progress, urging all stakeholders to adhere to timelines for completing the main dam construction. Ghising emphasized collective responsibility, stating that the Tanahun project’s reservoir nature would help alleviate electricity demand-supply imbalances, particularly during dry seasons.

The completion of the main tunnel marks a significant milestone, following the diversion of the river for main dam construction. Ghising urged project management, consultants, and construction professionals to expedite dam construction to meet project deadlines.

Looking ahead, Ghising highlighted plans for the Lower Seti Hydropower Project, aiming to address electricity demand in coastal areas during the dry season.

Kiran Kumar Shrestha, Managing Director of Tanahun Hydropower Limited, and Shyamji Bhandari, Acting Head of the project, provided insights into construction progress and challenges faced.

With an overall physical progress of 54%, the project aims for completion by 2083 (May 2026). Key components include foundation digging for the main dam under package-1 and tunnel construction and power house installation under package-2.

Package-3 involves the construction of a transmission line, with 72% progress already achieved. Additionally, the Tanahun rural electrification project aims to enhance local electricity supply, ensuring reliability and quality for residents.

The Tanahun hydropower project stands as a beacon of progress in Nepal’s energy sector, poised to meet the nation’s growing energy needs while fostering economic development and sustainability.

The project, with a total cost of $505 million, receives financial support from the Asian Development Bank ($150 million), Japan International Cooperation Agency ($184 million), European Investment Bank ($80.5 million), and the government and Nepal Electricity Authority ($80.6 million).