Construction Begins on Access Tunnel for Lower Seti Hydropower Project

April 13, Damauli (Tanahun) – The construction of the access tunnel for the 126-megawatt Lower Seti Hydropower Project has officially commenced in Devghat Rural Municipality-4, Tanahun. Tanahun Hydropower Limited, a subsidiary of the Nepal Electricity Authority, has entered into a contract with R.K. Hydro Engineering and Associates Pvt. Ltd. of Kathmandu to undertake the tunnel construction.

Project Chief Harikumar Shrestha informed that while the contract agreement was finalized on February 19, 2024 (7th Falgun 2080 BS), delays occurred due to the pending approval process for the use of explosives, causing temporary interruption in construction. Once the necessary approvals were secured, tunnel excavation work resumed.

According to Chief Shrestha, the access tunnel is a critical component of the hydropower project’s main infrastructure, serving a vital role in geological studies, exploration, and as a key access route. The Lower Seti Hydropower Project is a run-of-river scheme with a semi-reservoir, projected to generate an annual electricity output of approximately 5.2078 billion units.

The dam will be constructed on the Seti River near Sarangkot within Bandipur Rural Municipality, Tanahun, with a height of 32 meters and an estimated reservoir length of roughly 12.7 kilometers. Stored water will be conveyed through a 6.75-kilometer-long tunnel to the semi-underground powerhouse located at Gai Ghat in Devghat Rural Municipality-4.

The Detailed Project Report was prepared with grant assistance from the Asian Development Bank. The project’s estimated total cost stands at $227 million USD, with funding structured through 30% equity and 70% debt, as per Nepal Electricity Authority’s decisions.

Additionally, land acquisition procedures for approximately 146 ropani (7.46 hectares) of land designated for the powerhouse and employee housing have been initiated following budget allocation by the Nepal Electricity Authority. After becoming operational, the project is expected to produce 126 megawatts of electricity for at least six hours daily during the dry season.

Chief Shrestha emphasized the project’s importance as a cascade facility that will fully utilize the water released from the upstream Tanahun Hydropower Project reservoir. He highlighted the need for government prioritization in securing budget provisions to support this critical linkage.

Utilization of the Tanahun project’s transmission lines will eliminate the necessity for additional transmission infrastructure. Moreover, the project’s strategic location near major load centers such as Kathmandu and Bharatpur enhances cost-effectiveness and commercial viability. Grid connection agreements are already in place, and power purchase agreement negotiations are ongoing.

Shrestha also mentioned the requirement for a concrete bridge over the Trishuli River to ensure reliable access to the powerhouse and employee housing in Devghat Rural Municipality-4. The estimated cost for this bridge is around NPR 37 crore, necessitating multi-year budget arrangements.

The environmental impact assessment has been submitted to the Ministry of Forests for final approval. Financial support efforts are underway with the Japan International Cooperation Agency, while the Asian Development Bank has included the project in its 2027 implementation pipeline, according to the project chief.