Salient features of the Project

The Project components are located in the North Sikkim district of the state of Sikkim with Dam at the Chugthang Village and the Power House site at Singhik. The project utilizes the fall of head in the River course, of about 800 meters between these two villages.

 

The main components of the project are:

• 60 M high Concrete Faced Rockfill Dam (CFRD) with a Plastic Concrete Cut off Wall, 400 M downstream of the confluence of rivers Lachen Chu and Lachung Chu near village Chungthang.
• 2 Tunnel Spillways (with one acting as a Diversion Tunnel also) and one high level surface spillway on Left bank
• 1 Reservoir Flushing Tunnel, which acts as an Auxiliary Spillway also on the Right Bank.
• 2 Nos. Desilting Chambers to separate silt particles of more than 0.2 mm size.
• 13.86 KM long Head Race Tunnel of 7.5 M diameter (horse-shoe shape) with design discharge of 175 cumecs.
• 150 M high Surge Shaft of 15 M diameter.
• 2 Nos. 1160 M long Pressure Shafts of 4.0 M diameter each of which 633m Vertical and 533 m inclined.
• Underground Power House of 21.5 M x 48 M x 215.5 M for housing 6 units of 200 MW each vertical shaft Pelton turbines.
• 1080 M long D-shaped Tail Race Tunnel of 8.0 M x 8.0 M size.

 

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.

The First unit of the Project is scheduled to be commissioned in August 2011 and the sixth unit in Jan 2012, with one unit each in the intervening months.