ENERGY GENERATION:<<<The 1200 MW Punatsangchhu-I Hydroelectric Project is envisaged to generate 5700 million units in an average year>>>

Confluence of Phochhu and Mochhu river near Punakha Dzong

Punatsangchhu-I Hydroelectric Project Authority (PHPA-I) is an autonomous body set up for the implementation of the 1,200MW Punatsangchhu-I Hydroelectric Project (PHEP-I), the mutually beneficial Indo-Bhutan Friendship Project. The project’s implementation started on November 11, 2008. Originating at an altitude of ±7,000 masl in Gasa Dzongkhag (District) of Bhutan and fed by snow/glacial lakes from the Great Himalayan Range, the rivers Phochhu and Mochhu join at an altitude of ± 1212.2m masl at the iconic Punakha Dzong (Fortress) to form the Punatsangchhu river which then flows southerly to enter the Indian plains as Sankosh. This run-of-the-river Project located by the 7-21 km stretch of Wangdue-Tsirang National Highway in Wangduephodrang Dzongkhag in Western Bhutan is the first project under the 10,000MW Hydropower Development Initiative undertaken by the Royal Government of Bhutan (RGoB) and the Government of India (GoI). Designed to generate 5,670 million units of electricity in an average year, the Project utilizes 357 m of head available in about 11 km length of Punatsangchhu river. The Dam site is about 7 km downstream of Wangdue Bridge and all other project components are located on the left bank of the river between 7 km and 21 km downstream of the Wangdue Bridge.


The Main Civil Works of the project has been divided into three packages: MC-1, MC-2, and MC-3.


Construction of Diversion Tunnel, Dam, Intakes, and Desilting Chambers; including associated Hydro-Mechanical (HM) works was awarded to M/S Larsen & Tourbo

Construction of Headrace Tunnel (HRT) from Adit-I & Adit-II. This was awarded to M/S Gammon India Ltd and stands Completed.

Construction of Headrace Tunnel (from Surge Shaft End) , Surge Shaft, Butterfly Valve Chamber, Pressure Shafts, Power House, and Tailrace Tunnel works was awarded to M/S Hindustan Construction Company.

Transmission Line

Main Transmission

The 400 KV transmission system of the Project is entrusted to Bhutan Power Corporation Ltd. (BPC) (A RGoB Undertaking) on a “Deposit Work” basis. Power grid (A Government of India Undertaking) is the Consultant to BPC. BPC awarded the contract of two 400 KV Double Circuit Transmission Lines of 172 km length to M/s Jyoti Structures & Gammon (India) JV.


Latest News and Events


The Punatsangchhu-I Hydroelectric Project held its 23rd Authority meeting on November 24, 2022. The meeting was held in Thimphu, Bhutan.

Shri Alok Kumar, Secretary (Power), GoI accompanied by the HE Ambassador of India to Bhutan, the Joint Secretary (North), the Joint Secretary (Hydro) and other delegates briefly visited the Punatsangchhu-1 Project site on 30.10.2022. The delegation was received at Dochula by both MDs of PHPA-I and PHPA-II on 29.10.2022.

Besides the Powerhouse, the delegates also visited the Dam site and the proposed Barrage site while returning to Thimphu. read more>>>

The Punatsangchhu-I Hydroelectric Project held its 23rd Authority meeting on November 24, 2022. The meeting was held in Thimphu, Bhutan.

Participation of PHPA-I in the Dzongkhag’s Mass Cleaning Campaign Week:

The Dzongkhag Administration of Wangduephodrang has initiated a week-long cleaning campaign in the Dzongkhag w.e.f. 20-27 August 2022 with an aim to keep the district clean and green. As part of the initiative, the PHPA-I also participated in the cleaning campaign during which the National Highway Road stretch from Hesothangkha, Gaselo Gewog in the North to Rurichhu, Dagar Gewog in the South were combed thoroughly for any trash that were littered alongside the roads. read more>>>


Lowering of Last Rotor (315T) in the Generator Barrel.

The last assembly of Generator Rotor weighing 315,000Kg for Generating Unit-5 has been completed and lowered in the Generator barrel on December 29, 2021, and thereby assembly and lowering of all the Stators (266,000kg) and Rotors for 6 nos. of Generating Units stands completed. The 3 nos. of Generating units had been boxed up and the same is in progress for other Units.

Celebration of SFD at PHPA-I, Bjimthangkha

Social Forestry Day is observed across all institutions in Bhutan since 1985, coinciding with the Coronation Anniversary of His Majesty the Fourth Druk Gyalpo. As every year, this year too, the Social Forestry Day was observed by PHPA-I Management & Officials with the planting of tree saplings, hedges, stem cuttings, broadcasting of grass seeds to re-vegetate the Muck Disposal site of HRT Adit I in more>>>