The Dugar Hydroelectric Project will be located in Himachal Pradesh. (Credit: Ankur P, from Pune, India at commons.wikimedia.org)
Agreement signed for the construction of the project. (Credit: Department of Information & Public Relations, Himachal Pradesh)
The project will be located in Chamba District. (Credit: chambalover at commons.wikimedia.org)

The 500MW Dugar Hydro Electric Project is a proposed run-of-river scheme to be developed near Luj Village on Chenab River in the Chamba District of Himachal Pradesh, India.

The project, a concrete gravity dam, was first allotted to Dugar Hydro Power Ltd. (DHPL), a joint venture of Tata Power and Statkraft, by the Government of Himachal Pradesh.

Dugar Hydro Power prepared the Draft Detailed Project Report (DPR) of the project and submitted it to the Central Electricity Authority (CEA) for technical and economic clearance.

In September 2017, the allotment was cancelled, and the project was transferred to the National Hydroelectric Power Corporation (NHPC), a Government of India Schedule ‘A’ enterprise incorporated on 7 November 1975. The project was allotted to NHPC in August 2018.

The Himachal Pradesh Government signed a Memorandum of Understanding (MoU) with NHPC on 26 September 2019 to implement the project on Build Own Operate and transfer (BOOT) basis for 70 years, including DPR and pre-construction periods.

The Expert Appraisal Committee (EAC) recommended scoping clearance for the project in June 2020. A draft Environmental Impact Assessment (EIA) was prepared for NHPC in October 2021.

In April 2022, the Government of India technically approved the detailed project report of the project.

In August 2022, the Government of Himachal Pradesh and NHPC signed an agreement for the construction of the hydro electric project.

Location of the Dugar Hydro Electric Project

The Dugar Hydro Electric Project will be located in Tehsil Pangi of Himachal Pradesh.

The project will be situated about 10km from the Killar town and will have Udhampur Railway Station, Udhampur, Jammu and Kashmir and Pathankot Railway Station, Pathankot, Punjab as the nearest railway stations. The project site will be about 270km from Udhampur.

Bhuntar and Jammu in Jammu and Kashmir will be the nearest airports. Bhuntar will be about 279km from the project site and Jammu will be about 332km from the site.

Dugar Hydro Electric Project Details

According to the River Diversion Scheme, the Dugar Hydro Electric Project will include the construction of coffer dams, a 128m high concrete gravity dam from the deepest foundation level, a plunge pool, and diversion tunnels to divert the water of the Chenab River.

Two coffer dams upstream and downstream of the axis of the dam will be constructed with the top level fixed at El. 2,043.7m and El. 2,029.5m.

The dam will be located on the right bank of the Chenab River near the Luj Village. The elevation of the riverbed at the dam axis will be approximately 2,017m.

From the top, the length of the dam will be 210.65m with a design flood (PMF) of 9,425m3/s. It will have a full reservoir level of 2,114masl, a maximum reservoir level of 2,114masl, and a minimum draw-down level of 2,102.35masl.

Two horseshoe-shaped and gated tunnels of 11.5m diameter are proposed at the right bank of the Chenab River with upstream and downstream cofferdams. The tunnels of 463m and 577m in length can accommodate 2,700m3/s of design flood equivalent to a 25-year occurrence period during monsoon season.

There will be a gated ogee spillway consisting of an overflow gated ogee spillway (upper-level spillway) and a gated sluice spillway bays with a breast wall (lower-level spillway). The spillway will be kept at the highest possible level considering the Indus Water Treaty stipulations and the amount and nature of solid materials brought by the river.

For the upper-level spillway on the right bank of the Chenab River, one bay is proposed to remove logs and debris. It will have an inflow design flood at a height of 2,102.3m with a discharging capacity of 512.5m3/s at full reservoir level. The spillway will also have a trash boom to prevent logs and debris from entering the dam intake structure.

The power intake structures of the project will be located on the left bank of the Chenab River about 15m upstream of the dam axis with the invert level fixed at an elevation of 2,083m.

An outdoor pothead yard of 70m*50m is proposed upstream of the dam and just above the power intake structure’s top.

To transfer water from the intake structures to the powerhouse, two 7.25m diameter underground circular pressure tunnels have been proposed for the project. The 36m long upper-pressure tunnel will be followed by a 65.91m and a 96.32m long tunnel underground up to the bend to transfer water to their vertical shafts respectively.

The two vertical shafts of 118.09m in length will be divided into two lower horizontal pressure tunnels of 53.66m and 62.98m in length via a vertical bend.

The main access tunnel of the project will have two dimensions: a D-shaped 8m diameter of 397m initial length reducing to 7m diameter and another D-shaped tunnel for the final length of 164m which will open into the service bay area of the powerhouse.

A single 400m long tail race tunnel of 12.1m finished diameter will be housed within over a 200m high cliff.  It will be located on the left bank of the Chenab River. The tunnel will consist of two 8.5m diameter tail race tunnels.

Power Complex and Auxiliary Powerhouse Arrangement

An underground powerhouse complex has been proposed downstream of the dam and on the left bank of the Chenab River.

It will include four 103MW units for the main plant and two 44MW units for the auxiliary plant. The powerhouse can be accessed by a 560m long main access tunnel.

A transformer cavern will be located 40m upstream of the powerhouse cavern and the surge cavern will be located approximately 40m downstream of the powerhouse cavern.

The power intake structure of the auxiliary plant will have an invert relation of El. 2,089m.

Contractor Involved

The draft EIA report and an Environmental Management Plan (EMP) of the hydro electric project have been prepared by R.S. Envirolink Technologies.

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