About Us

LDHC Profile

Loktak Downstream Hydroelectric Corporation Limited is a joint venture company of NHPC Limited ( stake 74%) and State Government of Manipur (stake 26%) for implementation of Loktak Downstream Hydroelectric Project (66 MW) in Tamenglong district of Manipur to exploit the hydroelectric potential of tailrace discharge of Loktak Hydroelectric Project supplemented by Leimatak River. It is a subsidiary company of NHPC Limited.

PROJECT LOCATION:

Loktak Downstream Hydroelectric Project (66MW) is located on the river Leimatak in district Tamenglong of State of Manipur. Project areas come under the jurisdiction of Nungba sub-division.

SALIENT FEATURES

LOCATION:
State Manipur
District Tamenglong
River Liematak
Dam Site Near Tousang village
  • Nearest BG Rail Head
Dimapur
Nearest Airport Imphal
Latitude 24 ° 43′ 52.61″ N
Longitude 93 ° 35′ 7.62″ E

 

HYDROLOGY:
Catchment Area 546 Sq. Km
Average Annual Rainfall 1644 mm
  • Maximum 10 daily discharge
167 Cumec
  • Minimum 10 daily discharge
21 Cumec

 

RESERVOIR:
  • Full reservoir level (FRL)
EL 307.0 m
  • Minimum draw down level (MDDL)
EL 305.0 m
  • Gross Storage at FRL
300.6 Ham
  • Live Storage
67 Ham
SPILLWAY:
Type Gated Ogee Type
Design flood (SPF) 3070 Cumec.
Number of bays Four Nos.(including one emergency)
Crest of spillway EL 292.0 m
  • Size of each bay
10.5 m wide
Energy dissipation Stilling Basin with end sill
INTAKE:
Number and size Two,   5.0m(W)x3.0m(H)
  • Invert level at inlet
EL 298.0 m
Trash Rack Inclined Type

 

STAGE DIVERSION:
Diversion Discharge 1265 Cumec.
Number of Stages Two
  DAM
Type Concrete Gravity Dam
Dam Top elevation EL 309.0 m
  • Height of Dam above River Bed level
20.0 m

Height of Dam above Deepest

Foundation Level 30.0 m
  • Length of Dam at top
162.9 m

 

SPILLWAY:

Type Gated Ogee Type
Design flood (SPF) 3070 Cumec
Number of bays Four Nos.(including one emergency)
Crest of spillway EL 292.0 m
  • Size of each bay
10.5 m wide
Energy dissipation Stilling Basin with end sill

INTAKE:

       Number and size Two,   5.0m(W)x3.0m(H)
    Invert level at inlet EL 298.0 m
       Trash Rack Inclined Type

 

HEAD RACE TUNNEL:
  • Number
One
  • Size (finished diameter)
5.0 m
  • Shape
Horseshoe shaped
  • Length
5849 m
  • Design Discharge
55.46 Cumec
  • No. & Size of Construction Adits
Two No. & 5.6 m, D-shaped with
. one Gated plug (3mx3m)
SURGE SHAFT:
Number and Type One, Restricted Orifice Type
Size (finished diameter) 12.5 m
Shape Circular
  • Height of surge shaft
61.0
Top elevation EL 335.0 m
PENSTOCK:
Number One bifurcating to two
Type Steel lined
Shape Circular
Diameter (Steel Lined) 4.8 m bifurcating to 2.6 m
Length (4.8 m dia.) 722.0 m
Length (2.6 m dia.) 44.0 & 40.0 m
  • Adit to Penstock Bottom
6.0 m D – Shaped

 

  SWITCH YARD:
Size 125 m (L) x 64 m (W)
  POWER GENERATION:
Installed capacity 66 MW
Annual Energy generation in 90% 334.22 MU
dependable year at 95% M/c availability

CRITICAL EVENTS/ STATUTARY CLEARANCES:

  • Signing of Memorandum of Understanding

 

14.09.2007
  • Signing Memorandum and of Article of Association

 

  • Transfer of TEC from NHPC to JV
10.9.2009

 

06.08.2012

  • Defence Clearance
26.08.2013
  • In-principle (stage-I) Forest Clearance
03.03.2011
  • Environmental Clearance
16.01.2013
  • Techno Economic Clearance by CEA
05.05.2017