This
1200 MW (6 x 200MW) project is one of the largest hydro-electric projects
in India with 800m head. The project on completion will generate 5183
Gwh in 90% dependable year.
The main components
of the project are:
60 M high Concrete
Faced Rockfill Dam (CFRD) 400 M downstream of the confluence of rivers
Lachen Chu and Lachung Chu near village Chungthang.
2 Nos. Intake
Tunnels of 6 M diameter.
2 Nos. Desilting
Chambers of size 16 M x 21.2 M x 287 M to separate silt particles
of more than 0.2 mm size.
13.325 KM long
Head Race Tunnel of 7.5 M diameter (horse-shoe shape) with design
discharge of 175 cumecs.
121 M high Surge
Shaft of 20 M diameter.
2 Nos. 1135 M
long Pressure Shafts of 4.0 M diameter each plus bifurcations.
Underground Power
House of 21.5 M x 46 M x 220.5 M for housing 6 units of 200MW each
vertical shaft pelton wheel turbines.
980 M long D-shaped
Tail Race Tunnel of 8.0 M x 8.0 M size.
The pre-construction stage investigation works viz. sub-surface drilling, drifting, topographical surveys and geological mapping for the Project have been completed and the results from these are being utilized in the detailed engineering for the Project. The project has obtained all the statutory clearances and works have been started at the site. The project is scheduled to be commissioned within the XIth Five Year Plan.
Unique Features of the Project
Teesta Stage III is the largest HE Project under construction in Joint Sector in the country.
Best and most unique HE Project with high head of 800 m against short HRT length of 13.3 km.
Best studied and investigated project in the country by agencies like CWC/CEA, GSI, NHPC and TUL.
Most dependable hydrology with data of over 30 years period for arriving at the dependable flow.
Environment friendly project – Major project components underground, minimum impact on environment.
Despite the size of the project no Resettlement and Rehabilitation issues leading to no local/ R & R issues
Sikkim is politically most stable, peaceful and investor friendly state
Govt. of Sikkim has 26% Equity resulting in pro-active attitude of the Government and smooth implementation of the Project
Local people are pro-development leading to smooth implementation of the project
Less implementation time as most of the infrastructure works are in place.
