• Jhelum Tamak Hydroelectric Project is located on river Dhauliganga, a tributary of Alaknanda in Chamoli district of Uttarakhand. The dam site is approachable from Rishikesh by road via Rishikesh- Joshimath highway (National highway No.58) at a distance of 257 km and further 57 km from Joshimath upto the diversion site. The nearest rail head is Rishikesh and nearest airport is Jolly Grant, Dehradun.
    The Project is a run-of-river scheme, harnessing a head of about 207.54 m. As per the draft DPR, the proposed project involves construction of 28m high Barrage. The water conductor system consists of 2 nos. gated Power intake of size 3.8 m x 3.8 m each, 2 nos De-silting Chamber of size 220 m x 12 m x 13.6 m. The de-silting chambers converges, after a smooth transition to a 5.2m dia., 4.405 km long, horse shoe shaped, head race tunnel. The head race tunnel ends in a 12m dia. and 60m high u/s surge shaft. Further, one no. Pressure Shaft, 4.0m dia. is bifurcated into 3 nos. 2.30 m dia penstocks before entering into the machines in the underground machine hall of size 101.00 m x 19.5 m x 39.7 m. A Tail race tunnel of 7.0 m X 9.0 m D shape dia. and 308 m length, discharges the water back into the river.
    The project would afford an annual energy generation of 505.12 GWh in a 90% dependable year. The project is estimated to cost ` 1290.25 crores including IDC at Oct 2012 price level. The first year and levellised tariff from the project would be ` 6.05/ KWh and ` 5.22/ KWh respectively.

    Environmental Impact Assessment of Jelam Tamak H.E. Project
    Environment Management Plan For Jelam Tamak H.E. Project
    Environmental Impact Assessement And Management Plan For Jelam Tamak H.E. Project
  • 1.        Project Location  
    State Uttarakhand
    District Chamoli
    River    Dhauliganga
    Site Near Jelam Village
    2.        Hydrology  
    Catchment area 1666 km2
    Area under snow 879.00 km2
    Rain fed area 787.00 km2
    Elevation of Snow Line 4900 m a.s.l.
    Standard Project Flood 1906 m3/s
    3.        Reservoir  
    Full Reservoir Level (F.R.L.) 2648.5  m
    Minimum Draw-down Level (M.D.D.L.) 2638.8  m
    Length of Reservoir at FRL 3.3 km
    Area of Reservoir at FRL 37.92 Ha
    Gross storage 5.50 million m3
    Live storage 3.218 million m3
    4.        Barrage  
    Latitude 30º 37’ 35.4” N
    Longitude 79 º 49’ 39.5” E
    No. & size (W x H) of bays 6 bays, 8.0 m x 6.0 m each
    Height of the barrage 28.0 m
    Spillway Crest Level EL 2624.50 m
    Under Sluice Sill level EL 2623.50 m
    River Bed Level EL 2623.50 m
    Top of barrage EL 2651.50 m
    5.        Barrage Gates  
    Gate Type Radial
    No & size (W x H) 5 Nos., 8.0 m x 6.0 m
    Hoist Type Twin Hydraulic Cylinders
    6.        Under sluice Gate  
    Gate Type Radial
    No & size (W x H) 1 No., 8.0 m x 6.0 m
    Hoist Type Twin Hydraulic Cylinders
    Stoplogs Type (common for barrage & under sluice gates Vertical Lift Slide type
    No & size 1 No., 8.0 m x 8.30 m
    Hoist Type Gantry Crane using a lifting beam
    7.        Intake (On Right  bank)  
    Nos. Two
    Intake invert level EL 2630.40 m
    Gate Type Vertical lift fixed wheel type
    Gate Size (W x H) 2 Nos., 3.8 m x 3.8 m
    Hoist Type Electrically operated Rope Drum Hoist
    Type of Bulk Head Gates Vertical lift slide type
    Gate Size (W x H) 2 Nos., 3.8 m x 3.8 m
    Hoist Type Electrically operated Rope Drum Hoist
    8.        Trash racks  
    Type Fabricated steel panels
    Nos. 8 Nos.
    Size of opening (W x H) 3.0 m x 6.8 m
    Size of trash rack panels (W x H) 3.0 m x 1.828 m
    Sill level  2632.30 m
    Inclination of trash rack 10º (with vertical)
    Clear opening between the bars 100 mm
    9.        Intake Ducts  
    Nos. 2
    Size of each duct (W x H) 3.8 m x 3.8 m
    Length of each duct 24.9 m
    10.      Feeder Tunnels  
    Nos. 2
    Size of each tunnel 3.8 m, D-shape
    Length 146.0 m & 125.0 m
    11.      De-sanding Chambers  
    No. & Size (L x W x H) 2 Nos., 200.0 m x 12.0 m x 13.6 m
    Size of particles to be removed >0.2 mm
    Discharge for each chamber 38 m3/s
    Flushing discharge for each chambers 5.80 m3/s
    12.      Headrace Tunnel  
    Design Discharge 57.58 m3/s
    Shape Horseshoe
    Finished Size 5.2 m
    Length 4404.58 m
    Thickness of lining 300 mm
    13.      Surge Shaft  
    Type Restricted-orifice; Underground
    Diameter 12.0 m
    Orifice Diameter 2.3 m
    HRT invert at surge shaft  2603.80 m
    Surge shaft bottom (Top of orifice slab) 2611.0 m
    Surge Shaft Top 2671.0 m
    Total Height 60.0 m
    Upsurge level 2668.4 m
    Down surge level 2614 m
    14.      Pressure Shaft  
    Number and Diameter 1 Nos., 4.0 m 
    Grade of Steel ASTM A537, Class II
    Length of main Pressure Shaft 245.1  m
    15.      Penstock Valve  
    Type Lattice type Butterfly Valve
    Number One (1)
    Elevation of Valve Centre Line 2605.80 m
    Diameter 4.00 m
    16.      Intermediate Branch Penstock  
    Number and Diameter 1 Nos., 3.25 m
    Grade of Steel ASTM A537, Class II
    Length of penstock 11.0 m
    17.      Branch Penstocks (Unit penstocks)  
    Number and Diameter 3 Nos., 2.30 m
    Grade of Steel ASTM A537, Class II
    Length of penstocks 41 m, 28.30 m and 33.0 m respectively
    18.      Powerhouse  
    Location Underground, about 1 km  upstream of Tamak village
    Latitude 30º 36’ 45” N
    Longitude 79 º 47’ 15” E
    Dimensions (L x W x H) 101m x 19.5m x 39.7m
    19.      Transformer Hall cavern  
    Dimensions (L x W x H)  79 m x 13.5m x 22m
    20.      Main Inlet Valve  
    Type Spherical
    Number 3
    Elevation of Valve Centre Line 2420.50 m
    Diameter 1.65 m
    21.      Turbine  
    Installed Capacity 108 MW (3 X 36 MW)
    Turbine Type Vertical Axis Francis
    Number of Units 3 Nos.
    Turbine Centre Line El. 2420.50 m
    Rated Discharge per Unit 19.19  m3/s
    Turbine Speed 428.57 rpm
    Rated net head 207.54 m
    Maximum tail water level 2432.77 m (HFL)
    Minimum tail water level 2426.57 m
    Normal Tail Water level 2427.73 m
    22.      Generator  
    Type    Suspended Type
    Number 3 Nos.
    Generator Output 40.00 MVA
    Generator Voltage 11 kV ± 10%
    Generator Frequency 50 ± 5% Hz
    Power factor 0.9
    23.      EOT Cranes  
    P.H. crane:  Nos. and capacity 1 No.- 100 T / 20 T / 10T
    GIS crane:  Nos. and capacity    1 No. – 10 T
    Penstock valve crane:  Nos. and capacity     1 No. – 60 T / 16 T
    24.      Draft Tube Tunnel  
    Nos. and Sizes (W x H) 3 Nos., 5.5 m x 2.5 m
    Length of each tunnel 89 m
    25.      Collection Gallery  
    Length 58.45 m
    Width 12.0 m
    Invert Elevation. 2422.0 m
    Crown Elevation 2444.50 m
    26.      Tailrace Tunnel  
    Length 308.0 m
    Shape (W x H) 7m X 9m
    Tailrace Outlet Gate Type Vertical lift fixed wheel type
    Tailrace Gate Size (W x H) 7m X 6m
    Hoist Type Rope Drum Hoist
    Outfall weir sill elevation 2426.8 m
    27.      Switchyard  
    Location On the right bank of the river
    Area bounded by river, SH-45, MAT portal  and construction adit portal
    28.      Power Benefits  
    90% dependable energy 505.12 MU
    50% dependable energy 519.13 MU

Updated on : 27/06/2018