Arun – III Hydropower Project

The Arun-III hydropower plant will be developed on the Arun River in Sankhuwasabha District of Province 1, East Nepal. It is an export-oriented project with a power generation capacity of 900MW.

Estimated to cost $1.04bn, the hydropower plant will produce 4,018.87 million units of electricity a year. It is being developed on a build-own-operate and transfer (BOOT) basis by Satluj Jal Vidyut Nigam (SJVN) Arun 3 Power Development Company (SAPDC), a joint venture of the Government of India and the Government of Himachal Pradesh.

SJVN was established in 2013 with an aim to plan, promote, organise and execute the Arun-III power plant. SJVN signed a memorandum of understanding (MoU) for the execution of the project with the Government of Nepal (GoN) in March 2008.

SJVN will operate the power plant for a concession period of 30 years, following which the ownership will be transferred to the GoN. It will provide 21.9% of free power to Nepal during the concession period.

The Ministry of Science, Technology & Environment, GoN, approved the environmental assessment report for the project in August 2015. Construction of the hydropower plant commenced in May 2018 and completion is scheduled for 2022.

The project is expected to generate 3,000 jobs during construction in India and Nepal together.

Arun-III hydropower plant make-up

The Arun-III hydropower project will include the construction of a 70m-tall and 466m-long concrete gravity dam on the Arun River. The dam will have a crest level of 808m and six sluice gates. The storage capacity of the dam will be approximately 13.94 million cubic metres (Mm³).

The dam will include an 11.74km-long circular headrace tunnel with a diameter of 9.5m, two steel-lined pressure shafts, and four penstocks. The tailrace tunnel will have a length of 192m and a diameter of 10m.

“It will provide 21.9% of free power to Nepal during the concession period.”

The dam will also comprise four underground desilting chambers with a length of 420m, width of 16m and a height of 24m.

The powerhouse of the project will be underground and will be equipped with four vertical Francis turbine units each. The rated capacity of each turbine generator is 225MW. The powerhouse will have a gross head of 308m and a design head of 286.21m.

Power transmission

The output from the power plant will be transferred to the Nepal-India border through a 300km-long, 400kV DC transmission line, which will be routed along Diding (Nepal) to Dhalkebar (Nepal) towards Muzzafarpur (India).

Contractors involved

The contract for the main works of the project was awarded to Patel Engineering, while the hydro-mechanical works contract was awarded to Om Metals.

The electro-mechanical equipment works involving design, engineering, manufacturing and supply of the Francis turbines, as well as commissioning of the project will be carried out by BHEL under a contract worth Rs536bn ($83.7m).

Total Management Services provided supporting services, including air and water quality tests, field data collection and socio-economic survey of Project Affected Families (PAFs) for the environmental assessment report of the project.

Benefits of the hydropower project

The Arun-III project aims to assist the people surrounding the hydropower project by uplifting their socio-economic levels through the generation of employment for the locals, boosting the local trade and industries, and fostering entrepreneurship.

The hydropower project is also expected to strengthen the bilateral ties between Nepal and India.

A total of 269 families that are affected by the project will be provided with 30 units of electricity each free of cost every month. The project also aims to develop the area by constructing new roads, bridges and amenities such as schools, hospitals and community centres.