With the completion of Nepal’s largest 220 kV Basantpur-Dhungasanghu Transmission line, the projects under constructions in the region have sigh of relief.

The Basantpur-Dhungesanghu 220 kV double transmission line was constructed to integrate electricity from hydroelectric projects on the Tamor River and its tributaries into the national transmission system. The line is 35 km long and passes through elevations ranging from sea level to 3000 meters. It consists of 127 towers.

The Basantpur substation is expanding with 6 bays under the Basantpur-Dhungesanghu transmission line. As part of this expansion, 3 Beka devices are being installed and tested. The work is scheduled to be completed by the first week of March.

Kulman Ghising, the Managing Director of Nepal Electricity Authority, stated that there would be no issues with the electricity flow of the 73 MW Middle Tamor Hydropower Project, which is being constructed by Sanima Middle Tamor Hydropower Ltd. in Taplejung, after the completion of the Basantpur-Dhungesanghu transmission line.

The Basantpur-Dhungesanghu transmission line will connect to Central Tamor in a few weeks. We have received information that the final phase of the project is currently undergoing testing. Equipment installation and testing are being carried out at the Basantpur substation to connect the project's power. By the time Central Tamor starts generating electricity, the expansion of the Basantpur substation will be completed and it will be ready for electricity. Executive Director Ghising confirmed.

The construction of the first circuit of the Basantpur-Dhungesanghu 220 kV transmission line has been completed under the Koshi Corridor 220 kV transmission line project. The transmission line runs from Basantpur substation in Dharmadevi municipality of Sankhuwasabha to Dhungesanghu substation in Maivakhola rural municipality of Taplejung.

The transmission line and substation are ready. However, due to the inability to construct the hydroelectric projects, the 220 kV line must operate at a reduced capacity. The electricity generated by the hydroelectric projects, including Central Tamor, will be connected to the line and supplied to the Morang and Sunsari districts through the Inruwa substation. This will improve the voltage and ensure a reliable and high-quality power supply.

KIC International, India was contracted in January 2018 for $24 million under the Koshi Corridor Transmission Line Project Package-3.

The contract was for the construction of the Basantpur-Dhungesanghu 220 kV transmission line and the 132-33 kV substation at Dhungesanghu. Construction of the transmission line is complete, and the Dhungesanghu substation is in its final stage. The Nepal government and authorities, along with the concessional loan from the Export Import (Exim) Bank of the Government of India, funded the construction of the Basantpur-Dhungesanghu transmission line.

Currently, the second circuit of the transmission line and bay extension work are being constructed at Basantpur substation as part of the Koshi Corridor Transmission Line Project Package-4. The transmission line spans 35 km, with 15 km of wire already laid.

In October 2023, Nepal Hydro and Electric Ltd. signed a contract to work on this project. The expansion of the bay is currently underway. The entire package, which is being funded by the Nepal government and NEA, is expected to be completed within the next month and a half.

The Koshi Corridor Transmission Line Package-1 has constructed a 220 kV double circuit tower from Tumlingtar in Sankhuwasabha to Inruwa Substation in Bhokraha Narsingh Rural Municipality of Sunsari. The wire was pulled only on one side of the tower.

Package-2 has completed and put into operation 220 KV substations at Inaruwa in Sunsari and Tumlingtar, Baneshwar, and Vasantpur in Sankhuwasabha. Electricity from Tumlingtar and Dhungesanghu substations will be delivered to Basantpur substation. From there, it will be transmitted through a 220 kV line to Inruva substation and integrated into the national transmission system.

The Government of Nepal, along with authorities and the concessional loan of the Export Import (Exim) Bank of the Government of India, invested in the construction of substations and transmission lines at Tumlingtar, Vasantpur, and Baneshwar for the Koshi Corridor 220 KV transmission line project.

The hydropower projects under construction on the Arun and Tamor rivers, along with their tributaries, will connect to the Inruva substation via the Koshi Corridor 220 kV transmission line.

This corridor has been built to link the electricity generated by the hydropower projects in Bhojpur, Sankhuwasabha, Tehrathum, and Taplejung in the Koshi province to the national transmission line.

The Koshi Corridor transmission line project enables the transmission of up to 1,000 MW of electricity from Tumlingtar to Basantpur, another 1,000 MW from Dhungesanghu to Basantpur, and up to 2,000 MW from Basantpur to Inaruwa. This transmission line is currently the longest 220 kV line in Nepal.