• Project Date:03 September 2018
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  • Categories:Detailed Engineering Study


Located in the upper reaches of the Arun valley, Kimathanka Arun HEP (KAHEP) is northern most project proposed along the Arun river. The headworks of the project is located roughly 3.7 km South of the Nepal China border. The project aims to divert the snow-melt dominated perennial flow of the Arun and generate more than 2500 GWh of annual energy by utilizing a gross head of 380 m. KAHEP is proposed as a peaking run-of-the-river scheme with a design discharge of 149 m3/s, minimum daily peaking of 4 hours and an installed capacity of 143 MW.  

The main features of the project consist of a gravity dam, underground settling basin, a 4.4km long headrace tunnel, penstock shaft and underground powerhouse with tailrace tunnel. A 15 km long transmission line is anticipated for power evacuation from the powerhouse site to the proposed Haitar substation proposed by Rashtriya Prasaran Grid Company.

At present, the major challenge for project implementation is site accessibility, but this will change once the Biratnagar-Kimathanka road, which is currently under construction, is completed.

The salient features of the project, according to the Desk Study Report are as follows:

The Employer

Vidhyut Utpadan Company Limited

Project Location



Sankhuwasabha District, Province no. 1


27°45’ 25” to 27°50’ 00”


87°24’ 12” to 87°27’ 25”

Proposed intake site

Approximately 46 km upstream of the headworks area of Arun-3 HEP at right bank

Proposed powerhouse site

Approximately 1.2 km downstream of the Arun River and Chhujun Khola confluence.

Project Site Accessibility

Nearest all-weather road is at Chiuribas along Koshi highway, approximately 54 km north of Khandbari, headquarter of Sankhuwasabha District.



River basin

Arun river is a major tributary of the Sapta-Koshi River

Stream flow gauging station

Uwa Gaun gauging station

Catchment area

24835.58 km2

Design discharge

143 m3/s

Power and Energy



450 MW

Gross Annual Energy

2475.7 GWh