The construction of the diversion tunnel of the 216 MW Upper Trishuli-1 (UT-1) run-of-the-river hydroelectric project in Rasuwa District has been completed. The UT-1 is the largest hydroelectric project under construction with foreign direct investment in Nepal. The project in a press statement informed that a full concrete lining diversion tunnel with a length of 420 meters and diameter of five meters diameter has been successfully constructed. "The Trishuli river has been diverted via a diversion tunnel on Feb 28 to commence the construction activities of the head works," reads the statement. According to Tae Hak Yoon, CEO of Nepal Water and Energy Development Company (NWEDC), river diversion is a significant achievement in the development of UT-1. The project has completed a 4.5 km excavation of the 13.5 km tunnel, which includes the headrace, adit, and tailrace tunnel. The excavation work of the underground powerhouse has advanced by 21 percent, and the overall progress rate of the Project is 14 percent. The developer of the project plans to complete the construction within December 2026.

The project's main construction started in January 2022 and is estimated to complete in December 2026. According to the statement, approximately 700 workers work at the construction site, including 300 local residents from Project affected Rasuwa district. The Korean firm Doosan Eneribility is the engineering, procurement, and construction (EPC) contractor for the project.

UT-1 is expected to generate up to 1,533 GWh of electricity annually. Out of the total annual energy generated by the project, 38.75 percent will be generated during the dry season, which is higher than most of the other run-of-the-river hydropower projects in Nepal, thus contributing vastly to managing the dry season electricity shortfall. The project is considered attractive for the country's power system as it is close to the Kathmandu Load Center and will get 104 MW of electricity even in the dry season with high electricity demand. The generated energy will flow to the national grid by connecting it to the Trishuli-3B hub substation that the Nepal Electricity Authority is constructing currently. The USD 647.34 million project is financed through 70 percent debt and 30 percent equity. The project partners will provide an equity investment of USD 194.20 million. The credit oF USD 453.12 million is being provided by a group of international lenders, including the International Finance Corporation (IFC), Asian Development Bank (ADB), Korean Exim Bank (K-EXIM), Korean Development Bank (KDB), Asian Infrastructure Investment Bank (AIIB), FMO (The Netherlands), the British International Investment (BII), Proparco (France), and the OPEC fund for International Development (OFID). The shareholders of NWEDC include Korea South-East Power Company Limited, Korea Overseas Infrastructure and Urban Development Corporation, International Finance Corporation, and a local Nepali partner.