The Upper Tamakoshi Hydropower Project achieved a major milestone on Sunday with the completion of digging of 8.4km headrace tunnel, which channels water diverted from the river to the power house where electricity is generated.

Energy Secretary Anup Kumar Upadhyaya and Nepal Electricity Authority Managing Director Kul Man Ghising were also present at the project site when the major breakthrough occurred.

The Dolakha-based 456-megawatt project had started tunnel excavation works before the 2015 earthquakes. However, the disaster, which was followed by Indian trade blockade, delayed tunnel construction works.

With Sunday’s achievement, 92 percent of the project’s work has been completed, according to project chief Bigyan Shrestha.

The national pride project is planning to bring the first unit of the plant into operation in mid-July following which 76MW of electricity would be added to the national grid. The project has a total of six units. The other five units will start generating electricity within five months of the first unit being switched on.

The energy produced by the project will be transmitted to a substation at Khimti via the 220 kV Gongar-Khimti transmission line which is currently under construction. The power evacuated to the Khimti substation will be transmitted to Kathmandu Valley and other energy-hungry neighbouring cities.

After the Upper Tamakoshi roars into life, Nepal Electricity Authority (NEA) will be in a position to export electricity to neighbouring India. The state-owned power utility is one of the promoters of the project.

During the wet season, surplus energy can be transmitted over the Khimti-Dhalkebar transmission line to the Dhalkebar substation and on to the Dhalkebar-Muzaffarpur cross-border transmission line for export to India.

The Upper Tamakoshi Hydropower Project has been expediting the construction of the 47-km Gongar-Khimti transmission line which will be used to evacuate the electricity generated by the plant.

The project needs to install 127 transmission line towers. “Around 90 percent of this work has also been completed,” Shrestha said.

The national pride project was originally scheduled to be completed in mid-July 2016, but the earthquake, Indian trade blockade and various technical and social issues pushed back the completion date. Before the earthquake hit the country, the project had completed 79 percent of the civil works. It faced cost overruns due to the delays. The project is now expected to cost Rs42 billion, up from the previous estimate of Rs35.3 billion. The project is the first major hydropower project being developed with domestic financial resources and significant participation of project-affected locals and the general public. The government, financial institutions and public enterprises, including Nepal Telecom, Employees Provident Fund, Rastriya Beema Sansthan, and Citizen Investment Trust, have invested in the project. The project is preparing to float shares to the public, including locals in the project-affected areas, in December. It plans to issue 25 percent of the shares worth Rs2.64 billion at an initial public offering (IPO) and wrap up the share distribution process by March 2018.