Overview:
The Shongtong Karcham HEP is a 450 MW run-of-the-river project being developed by Himachal Pradesh Power Corporation Limited (HPPCL) on the Sutlej River in Kinnaur district. Designed with minimal surface disruption and high-efficiency underground systems, it is expected to generate approximately 1,594 million units (MU) of electricity annually. Once operational, it will strengthen Himachal’s position as a hydropower leader in India.
📍 Location & Key Details
| Attribute | Details |
|---|---|
| Coordinates | Near Powari village, Kinnaur |
| Elevation | ~1,800 meters above sea level |
| River | Sutlej |
| Installed Capacity | 450 MW (3 × 150 MW Francis turbines) |
| Project Type | Run-of-the-river |
| Operator | HPPCL |
| Status | Under construction (target completion: Nov 2026) |
🏗️ Engineering Highlights
- Diversion Barrage:
A 102.5-meter-long barrage near Powari diverts up to 406 cumecs of Sutlej water into the system. - Sedimentation Chambers:
Four underground chambers, each 300 meters long, remove silt before water enters the headrace tunnel. - Headrace Tunnel (HRT):
A 8.02 km-long, 10-meter diameter circular tunnel carries water to the surge shaft. - Surge Shaft & Pressure Shafts:
- Surge Shaft: 39.5 meters in diameter
- Pressure Shafts: Three steel-lined shafts (5.1 m diameter, 211 m long) feed the turbines.
- Powerhouse:
Underground facility near Ralli village, housing three vertical-axis Francis turbines.
🌄 Environmental & Strategic Context
- Minimal Surface Impact:
Most components are underground, preserving the fragile Himalayan landscape and minimizing displacement. - Clean Energy Contribution:
Will supply power to over 800,000 households, reducing carbon emissions and fossil fuel dependency. - Geological Challenges:
The project faced delays due to fragile rock strata, monsoon disruptions, and proximity to NH-5 and local settlements.
🧭 Accessibility
- Nearest Towns:
- Reckong Peo (~10 km)
- Powari and Ralli (project villages)
- By Road:
Located along NH-5, about 220 km from Shimla via Rampur and Tapri. - By Train:
Nearest major station: Shimla (broad gauge access via Kalka) - By Air:
Shimla Airport (~230 km) or Chandigarh Airport (~350 km)
