The construction of the Dhalkebar-Interconnection 400 kV transmission line section of the Hetauda-Dhalkebar-Interconnection transmission line has been completed to strengthen the domestic power transmission system and to expand reliable electricity trade between Nepal and India.

A 154-kilometer, 400 kV double circuit transmission line has been constructed from Dhalkebar in Dhanusha to the Bhojpur-Bhokraha Narsingh Rural Municipality-4, located in Sunsari, through Inaruwa substation. The transmission line is capable of transmitting approximately 4,000 megawatts of electricity.

Construction had begun by dividing the transmission line into two sections from the Hetauda substation located in Thana Bhanjyang, Ward 11 of Hetauda Sub-Metropolitan City, Makwanpur, to the Inaruwa substation, spanning a distance of 288 kilometers.

Two sections transmission line: Hetauda-Dhalkebar, spanning 134 kilometers, and Dhalkebar-Inaruwa, spanning 154 kilometers. Among these, the construction of the Dhalkebar-Inaruwa section has been completed, while the construction of the Hetauda-Dhalkebar section is underway.

Kulman Ghising, the Managing Director of the Nepal Electricity Authority, has emphasized the significant achievement of completing the Dhalkebar-Inaruwa section, stating that it is crucial for enhancing the overall transmission system quality and reliability of the country and for increasing the volume of electricity trade between Nepal and India.

Due to the unavailability of our own transmission infrastructure, currently, only 800 megawatts of electricity import-export is possible through the Dhalkebar-Muzaffarpur inter-country transmission line in operation. However, after the completion of the Dhalkebar-Inaruwa section, it will be possible to increase the volume of electricity trade. Additionally, if there is excess electricity coming to the Inaruwa substation via the Koshi corridor, it can be exported to India via the Dhalkebar-Inaruwa transmission line. This was stated by Managing Director Ghising.

“The capacity of the existing 132 kV transmission line was causing voltage drops, making it difficult to transmit electricity from Dhalkebar to Inaruwa, as it couldn’t handle the load. Now, with the 400 kV transmission line, sufficient electricity can be transmitted, and voltage improvement will mainly enhance the electricity supply to the Morang-Sunsari industrial corridor.”

The construction of the Inaruwa 400 kV substation has been completed and it is now operational. Currently, to improve the overall electricity supply in the region, including the Sunsari-Morang industrial corridor, the process of upgrading the capacity of the existing Inaruwa-Duhawi 132 kV transmission line by replacing its old conductors with high-capacity (HTLS) ones has begun.

This process will approximately double the capacity of the transmission line, allowing it to handle a current flow of about 200 megawatts of electricity. Additionally, construction is underway for a 132 kV transmission line from Inaruwa to Barju and a 132 kV substation in Barju.

A proposal has been made for the Inaruwa-Purnia transmission line for electricity trade between Nepal and India, as well as for trade among Nepal, India, and Bangladesh. Additionally, the Inaruwa-Anarmani 400 kV transmission line proposal has been made. The Korea Export Import (EXIM) Bank is providing favorable loans for the Inaruwa-Anarmani transmission line project.

417 towers have been constructed for the Dhalkebar-Inaruwa transmission line. To cross the Sapta Koshi River, 11 towers have been erected. The foundation piles for the towers across the Koshi River, spanning 5 kilometers, are 24-32 meters deep. One tower has 16 pile foundations. Construction of the transmission line became significantly complex after one tower, affected by floods in the Koshi River two years ago, collapsed.

Director Shyam Kumar Yadav explained that the construction has been affected due to various reasons such as the COVID-19 pandemic, floods in the Koshi River, demands for route changes of the transmission line, local obstruction to construction, interim orders from the Supreme Court, utilization of forest land, and approval processes for tree cutting.

Director Yadav mentioned that due to the interim court order in the Siraha transmission line area, work had been halted for four years, and the project had to undergo three preliminary Environmental Impact Assessments (EIAs). He stated that now that the Dhalkebar-Inaruwa section construction has been completed, all manpower will be directed towards the construction of the Dhalkebar-Hetauda section. Currently, work is underway to string wires for the transmission line from Dhalkebar towards Hetauda. So far, 45 kilometers of wires have been strung.

Some locals from Wards 15, 16, and 17 of Hetauda Sub-Metropolitan City have been demanding a change in the route of the transmission line. They have been obstructing the construction for about seven years. In the Hatiya area, 14 towers are yet to be constructed, and in Thana Bhanjyang Ward 11 of Hetauda, 2 towers out of 16 remain to be built.

The Hetauda-Dhalkebar-Inaruwa transmission line project traverses through hilly, Siwalik, and Terai regions. The transmission line covers 10 districts including Makwanpur, Bara, Rautahat, Sarlahi, Mahottari, Dhanusha, Siraha, Saptari, Udayapur, and Sunsari.

A contract was signed in Magh of 2069 (January/February 2013) to complete construction within 30 months. The Hetauda-Dhalkebar-Inaruwa 440 kV transmission line runs parallel to the existing 132 kV transmission line and is close to the East-West Highway, generally running parallel to it.

The right-of-way (ROW) area of the transmission line is 23/23 meters from the centerline of the transmission line. The project requires the clearing of trees occupying 518 hectares of forest area and the acquisition of 30 hectares of privately owned agricultural land. In the ROW, 475 hectares of private land and 171 houses and other structures will be affected. Among these, the damage compensation for the ROW in the Dhalkebar-Inaruwa section alone is estimated to be around 5 billion Nepalese Rupees.