Planned Project

 

(I)    Kanhar Pumped – Storage Hydroelectric Project

 

1.1              Introduction

 

Kanhar Hydroelectric Project would be a part of Kanhar River development Scheme of which irrigation portion is being implemented by water Resources Department, Government of  Bihar. The Kanhar Reservoir at Baradih is primarily and essentially meant for providing irrigation to drought-prone area of Palamau district. The district is chronically drought affected and irrigation provided in the region is quite inadequate this results in frequent failure of crops. By storing water of the river Kanhar, there would be considerable relief in overcoming aforesaid problems. The power development will be secondary utilization.

 

Salient Features

 

Location         

 

            1.         State                                                    -           Bihar

            2.         District                                                 -           Palamau

            3.         River                                                    -           Kanhar

            4.         Situation (Dam)                                    -           Near Barahdih Village

            5.         Forebay Dam                                       -           Near Chinea Village

            6.         Power House                                       -           Near Lowadoni Village

            7.         Police Station                                       -           Ranka

            8.         Sub-Division                                         -           Garhwa

 

Reservoir at Baradih

 

            1.         Maximum water level (top of gate)        -           EL 414.33 M

            2.         Full reservoir level                                 -           EL 413.41 M

            3.         Dead storage level                                -           EL 396.34 M

            4.         Gross storage at M.W.L.                      -           60.108 hect-metre

            5.         Storage at F.R.L.                                  -           57897 hect-metre

            6.         Dead storage capacity                          -           5250 hect-metre

            7.         Live storage capacity                            -           52,647 hect metre

            8.         Reservoir area at F.R.L.                       -           6342 hect

            9.         Reservoir area at M.W.L.                     -           7012 hect

 

Dam Baradih

 

            1.         Type of Dam                            -           Rolled earth filled dam of non     

                                                                                    homogenous material Combined with

                                                                                    masonary spillway.

            2.         Elevation of top of dam                         -           417.99 M                                                                                                                                                                    

            3.         Maximum height of dam from foundation-          42.99 M

            4.         Lowest bed level of river                       -           374.69 M

 

Spillway (Baradih)

 

            1.         Type of spillway                                   -           Ogee type

            2.         Length of spillway                                 -           377.74 M

            3.         Spans                                                   -           16 nos.

            4.         Crest level                                            -           404.42 M

            5.         Design head                                          -           9.90 M

            6.         Design discharge                                   -           15922 cumecs

            7.         Type of gate                                         -           Radial

            8.         Size of gate                                           -           15.85 M X 9.91 M

 

Canal (Main Trunk canal and others)

 

            1.         Gross command area                            -           1.58 lacs. hect.

 

            2.         Culturable command area                     -           0.67 lacs hect.

 

            3.         Design discharge at head          

           

                        a)         Main trunk canal                       -           63.92 cumecs

                        b)         Right high level canal                 -           7.54 cumecs

                        c)         Left high level canal                   -           5.86 cumecs

                        d)         Left low level canal                   -           39.38 cumecs

                        e)         Right low level canal                 -           8.10 cumecs

 

            4.         Bed width of canal at head                   

 

                        a)         Main trunk canal                       -           4.27 M

                        b)         Right high level canal                 -           10.67 M

                        c)         left high level canal                    -           8.23 M

                        d)         Left low level canal                   -           2.59 M

                        e)         Right low level canal                 -           10.98 M

 

            5.         Full supply depth of canal at head                     

           

                        a)         Main trunk canal                       -           3.81 M

                        b)         Right high level canal                 -           1.22 M

                        c)         Left high level canal                   -           1.22 M

                        d)         Left low level canal                   -           3.35 M

                        e)         Right low level canal                 -           1.22 M

 

            6.         Lengths of canal           

           

                        a)         Main trunk canal                       -           28  K.M

                        b)         Right high level canal                 -           75.83 K.M.

                        c)         Left high level canal                   -           58.84 K.M.

                        d)         Left low level canal                   -           78.35 K.M.

                        e)         Right low level canal                 -           42.35 K.M.

 

            7.         Length initiated section 

 

                        a)         Main trunk canal                       -           28 K.M.

                        b)         Right high level canal                 -          

                        c)         Left high level canal                   -          

                        d)         Left low level canal                   -           65.14 K.M.

                        e)         Right low level canal                 -          

           

            8.         Length in unlined section

 

                        a)         Main Trunk Canal                     -          

                        b)         Right high level canal                 -           75.83 K.M.

                        c)         Left high level canal                   -           58.84 K.M.

                        d)         Left low level canal                   -           13.21 K.M.

                        e)         Right low level canal                 -           42.35 K.M.

 

            9.         Intensity of Irrigation                             -           85%

 

                        a)         Maximum water level                -           390.24 M.

                        b)         Full reservoir level                     -           390.24 M

                        c)         Minimum draw down level        -           379.87 M

                        d)         Gross storage at FRL               -           11.68 MM3

                        e)         Live storage at FRL                  -           9.305 MM3

                                f)          Dead storage                            -           2.375 MM3

                                g)         High of froebay dam                 -           28 M

                        h)         Length of forebay dam              -           2 KM.

                        i)          Type of dam                             -      Earthen, Masonary and concrete

 

10.              Lower Reservoir at Lowadoni

           

            a)         Full reservoir  level                    -           291.15 M

            b)         Minimum drawn-down level      -           287.19 M

            c)         Gross storage at FRL               -           11.40 MM3

                d)         Live storage at FRL                  -           6.00  MM3

                e)         Dead storage                            -           5.40  M M3

            f)          Type of dam                             -           Earth filled

 

11.              Intake Structures

 

            a)         Length                                      -           105 M

            b)         Type                                        -           54 meters-concrete, 51                                                                                                              meters-Masonary

            c)         Size of bell mouth opening         -           8.25 M

            d)         Trash Rack                               -           Provided

            e)         Gate                                         -           Full gate and stop log

 

12.              Spillway

 

            a)         Type                                        -           Surface

            b)         Length                                      -           115 M

            c)         Span                                        -           7 Nos.

            d)         Crest level                                -           388.64 M

            e)         Design head                              -           1.5 M

            f)          Design discharge                       -           345 Cumecs

 

13.              Penstocks/Pressure shafts

           

            a)         Diameter                                  -           5500 MM (internal)

            b)         Type                                        -           Steel liner Type

            c)         Plate thickness                          -           i)20mm to 28 mm-IS                                                                                                                  2002 GR. 2A

                                                                                    ii) 22 mm-IS 226 H.T.S.

            d)         Length of penstock/pressure shaft-        410 meters

 

14.              Power House              

                       

a)      Size                                                -           27 m (wide) x 80m (long) x

                                                                                    43m (high)

            b)         Type of Turbine                        -           Vertical francis (reversible                                                                                                          type)

            c)         Nos.  & size of Unit                  -           3 x 10 MW

            d)         Diameter of Turbine                  -           5000 MW

            e)         Centre Line of Units                  -           EL 267.19m

            f)          Machine hall level                     -           EL 279.00mm

            g)         S-bay floor level                       -           EL 279.00m

            h)         Top of power house                 -           EL 298.00m

 

15.              Tail Race System         

 

            a)         Minimum tail water level            -           EL 287.19m

            b)         Maximum tail water level           -           EL 291.10m

            c)         Size of tail race pool                 -           60 x 40m

            d)         Slope of tail race pool               -           1 in 2

            e)         Tail race channel bed width       -           14 m

            f)          Side slopes                               -           1 : 1.5

                                   

16.              Transmission line          

           

            220 KV Kanhar to Garhwa                  -           60 kms.

            (Feeder I & II)                                     (Circuit length)

 

17.              Power Generation                                 -

           

            a)         Cost per KW installation           -           Rs. 8427.00

            b)         Annual Energy benefits              -           373.7/Million Units

            c)         System cost of energy generation -        Rs. 0.61/kwh

            d)         Nett financial returns                 -           Rs. 3043.11 lacs/year

            e)         Annual return                            -           12.04%

 

 

(II) Sankh Hydroelectric Project

 

 

0.1              Executive Summary:

 

·           River Sankh, a major tributary of the Brahmani basin an area of 6478 km2  and in its 203 km. Long coarse drops from an elevation of +1037m to 192m.

 

·           The hydro power potential of the river can be developed in five stages.

 

·         Stage-II with an installed capacity of 186 MW can be taken up first in the development sequence, the planning and designs for stage II have been presented in the report (yield from Bihar Catchment).

 

·          Stage-II development envisages a dam at Turuma where the river drains an area of 116 km2 (Bihar catchment only) and 2046 km2  of total catchment.

 

·           The 90% dependable yield of the river (Bihar catchment only) at the Turuma has been estimated as 463.20 million m3 and the average annual yield 687 million m3 in the river portion.

 

·          The site is geologically suitable for construction of a rolled fill earth dam in the river portion with masonary gravity spillway on the right flank and masonary power dam on the left flank.

 

·          The dam extends over a length of 1236m and maximum height in earth dam portion is 47.05 m.

 

·           The portable maximum flood for which the spillway has been designed is 14600 cumecs.

 

·            The reservoir has a gross capacity of 867.62 million cumec at FRL 680m.

 

·           The Turuma, power house at the to of the dam on the left flank has an installed capacity of 2 units 3 MW each, and the tail race is let into a power channel.

 

·           The power channel from Turuma traverses 30.8 km. And empties into forebay at Budhamba. The Channel has a design discharge of 18 cumecs.

 

·           The Budhamba forebay dam has maximum height of 31.30 m extending over a length of 800m occupying two dykes on the left and is designed as a rolled fill earth dam. 20m waste weir have been provided at the forebay dam.

 

·           The forebay has a pondage of 1.9 million cumec catering to a day’s requirement.

 

·          The water conductor system comprises a head race tunnel 226.3 m log and a penstock 319m long. Bifurcating at the end of feed 2 units of 90 MW each.

 

·          The Sarubera power house has installed capacity of 2 units 90 MW each and the tail race  is let into Kasnjor nala which joins Sankh finally.

 

·           The Sarubera power house with an average net head of 180m is considered ideal for operating  as a peak load station with load  factor of about 15%.

 

·           The estimated cost of the project is Rs. 526.70 crores.

 

·           The annual energy generation of both power houses is 271.30 Gwh in a 90% dependable year.

 

·           The project is scheduled to the completed in 7 years from start.

 

·             The cost of generation is estimated to Rs. 2.54 per kwh.

 

1.5  TURUMA intake and penstock intake

 

                  Type                                        -           Bell Mouth

                  Size and No. of events               -          2.92m x 10.21 m – 2 nos.

                  Crest level                                -           EL 646.26m

 

      Penstock

                  Numbers                                  -           Two nos. and one by-pass channel

                  Diameter                                  -           3.00m

                  Length                                      -           40 m

                  Discharge                                 -           18 cumecs each

 

1.6 TURUMA Power House

 

                  Type                                        -           Surface

                  Type of turbine                         -           Kaplan-vertically mounted

                  Installed capacity                      -           2 nos. x 3 MW

                  Size of Power House                -           29 m x 17 m

                  Average net head                      -           27 m

 

1.6  Power Channel

 

                  Type                                        -           Open channel –lined

                  Section                                     -           Trapezoidal

                  Bed width                                 -           3.0 m

                  Side                                         -           slopes 1.25:1

                  Longitudinal                              -           slopes 1.8,000

                  Full supply depth                      -           2.60m

                  Free board                               -           0.75 m

                  FSL inlet                                  -           EL 638.50m

                  FSL outlet                                -           EL 632.80m

                  Design discharge                       -           18 cumecs

                  No. of X-diagrams                   -           17

                  Length                                      -           3.8 km.

 

1.8  BUDHAMBA Forebay Dam

 

                  Type                                        -           Rolled fill earth dam

                  MDDL                                     -           +630.95m

                  FRL                                         -           +633.50m

                  Pondage                                   -           1.9MM3

                  Bed level                                  -           EL 606.70m

                  Top of dam                              -           EL 638.00 m

                  Height                                      -           31.30m

                  Length at top                            -           EL 800m

                  Top width                                 -           9m

 

1.9  Waste Weir

 

                  Type                                        -           Ungated board crested weir

                  Crest level                                -           EL 633.50m

                  Height                                      -           2.50m

                  Length at crest                          -           20 m

 

 

1.10 BUDHAMBA Intake

 

                  Intake   type                              -           Bell mouth

                  Size and No. of vents                -           2 Nos.

                  Crest level                                -           EL 618m

     

1.11 Water Conductor

     

                  Head race Tunnel                     -          

                  Length                                      -           226.3m

                  Discharge                                 -           165 cumecs

                  Size and shape                          -           one no. 5.25m dia.

                  Penstock

                  Size and Number                      -           One no. 5.25 m dia

                  Length                                      -           5.25m dia. 319m

 

1.12                      Sarubera Power House

     

                  Type                                        -           Surface

                  Type of turbine                         -           Vertical shaft francis

                  Size                                          -           75m x 45m

                  Installed capacity                      -           2Nos. x 90 MW

                  Service Bay level                      -           EL 461.75m

                  Average net head                      -           180m

                  Tail water level                         -           EL 452.60m

 

1.13                      Tail Race Channel        

     

                  Type                                        -           Unlined open channel

                  Section                                     -           Trapezoidal

                  Bed width                                 -           20m

                  Longitudinal slope                     -           1 in 8000

                  Length                                      -           1.90 Km

                  Full supply depth                      -           4.00m

                  Bed level at inlet                       -           EL 448.50m

 

1.14           Abstract of Cost                       -           (Based on Feb, 1996 price level)

                                                                              Amount in Rs. lakh – 52670

 

1.15           Construction period                  -           7 years

 

1.16           Power Generation                     -

     

                  Installed Capacity                     -           186 MW

                  Turuma Power House               -           2x3 MW

                  Sarubera Power House              -          2x90 MW

                  Annual Generation                    -           90% dependable year

                  Firm                                         -           271.30 Gwh

                  Secondary                                -           30.10 Gwh

                  Cost of generation at Bus-Bar. Rs. 2.54/Kwh