Koteshwar HEP, about 22 km downstream of Tehri Dam, is an integral part of Tehri Hydro Power Complex (2400 MW). It consists of a 97.5m high concrete gravity dam across river Bhagirathi at Koteshwar and a surface power house accommodating four conventional type (Francis) generating units of 100MW each on the right-bank. The dam is provided with spillway having 4 bays to pass the probable maximum flood (PMF) discharge of 13243 Cumecs. The overflow spillway and energy dissipation arrangement has been located centrally in the river course itself. The Koteshwar reservoir has live storage capacity of 35.0 MCM and functions as lower (balancing) reservoir for Tehri PSP.

Water released from Tehri Reservoir is regulated at Koteshwar HEP for maintaining continuous flow of water in the river downstream of Koteshwar for irrigation purpose and maintaining aquatic life as well as safety of population and pilgrims at places such as Deoprayag, Rishikesh and Haridwar. At least, one machine of KHEP runs continuously to help maintain continuous flow. KHEP is also facilitating the functioning of Tehri Hydro Power Complex as a major peaking station in the Northern Grid.

All four units (Unit-I to IV) were synchronized with the Northern Grid in Mar’ 2011, Mar’ 2011, Jan’ 2012 & Mar’ 2012 and are in commercial operation w.e.f. 1st Apr’ 2011, 26th Oct’ 2011, 13th Feb’ 2012 & 1st Apr’ 2012 respectively.

SALIENT FEATURES

Location
State  Uttarakhand
District  Tehri Garhwal
Vicinity  Koteshwar Dam on river Bhagirathi is located near  Pendaras Village about 22 Km. downstream of Tehri Dam site.
Hydrology
Catchments Area  7,691 sq. km. at dam site
Snow catchments  2,328 sq. km.
Design flood  13,240 cumecs
Annual Run off  8.14 Km3 
Annual normal water flow  258.0 cumecs
Storage Reservoir
Full Reservoir Level(FRL)  EL. 612.5 m.
Maximum Flood Level(MFL)  EL. 615.0 m.
Minimum Draw Down Level(MDDL)  EL. 598.5 m.
Gross Storage upto FRL  88.9 MCM.
Live Storage Capacity  35.0 MCM
 

TECHNICAL FEATURES

Diversion Tunnel
Size & Type 8.0 m. dia. Horse shoe type
Length 593.0 m.
Discharge 1180 cumecs
Dam  
Type Concrete Gravity
Maximum height above Deepest Foundation Level 97.5 m.
 
Elevation of Top of dam  EL 618.5 m.
Crest Length  300.50
Length of non-over-flow section 196.50 m
Spillway
Discharge Capacity  
at FRL(612.5 m.)  9,140 cumecs
at MFL(615.0 m.)  13,240 cumecs
Number of bays  4
Bay width  18 m.
Crest Elevation  594.50 m.
Type of Service gates  Radial
Size of Gates 18 m. x 16 m.
Power Intake
Location Right Bank integrated into water  retaining structure.
Intake Sill Level 582.5 m.
Number and size of Penstocks 4 nos. 6.2 m. dia.
Type of service gate Fixed wheel
Power House
Type Surface at toe of dam
Location Right Bank
Number of Units 4
Rated Unit Capacity 100 MW
Installed capacity 400 MW
Type of Turbine Vertical shaft Francis type
Max. head 75.0 m.
Minimum head 58.0 m.
Rated head 69.0 m
Max. Flow through each Unit at rated head 161 cumecs
Switch Yard
Type Outdoor on surface 400 KV
Size 215.5 m x 136 m.
Power Generation
   
Design Energy in 90% dependable year 1155 MU
  1. Peaking Power- 400 MW
  2. Design Energy-1155MU ( 90% dependable year)
  3. Regulation of water releases from Tehri Reservoir for irrigation Purposes
  4. Koteshwar Reservoir will function as the pre requisite lower reservoir for Tehri PSP