Information on some major DAM projects

Bhakra Nangal Project

Bhakra DamBhakra Dam Bhakra Dam is a majestic monument across river Sutlej. Its construction was taken up first after independence, for the uplift and welfare of the people of Northern Region. The construction of this project was started in the year 1948 and was completed in 1963 . It is 740 ft. high above the deepest foundation as straight concrete dam being more than three times the height of Qutab Minar. Bhakra Dam is the highest Concrete Gravity dam in Asia and Second Highest in the world. The water stored at Bhakra has a tremendous potential of generating hydroelectric power. There are two power houses namely Left Bank Power Plant and Right Bank Power Plant. The power houses are connected on either side by underground cable galleries with the switch yard from where transmission lined take off. The Salient features of Bhakra Dam and Power houses are as below.

Bhakra Dam

Total cost of the Project	Rs. 245.28 crore
Type of Dam	Concrete straight gravity
Height above the deepest foundation	225.55 metres (740 feet)
Height above river bed	167.64 metres (550 feet)
Length at top	518.16 metres (1700 feet)
Width at top	9.14 metres (30 feet)
Length at bottom	99 metres (325 feet)
Width at base	190.5 metres (625 feet)
Elevation at top of dam above mean sea level	518.16 metres (1700 feet)
Steel used	101600 tonnes (100000 tons)

Reservoir

Catchment area	56980 Sq. kilometres.
Normal reservoir level	EL. 512.06 meters (EL.1680 feet)
Dead storage level	EL.445.62 meters.
New area irrigated	60 lakh acres.
Area of reservoir.	162.48 sq. kilometres (62.78 sq.miles)
Length of reservoir.	96.56 kilometres.
Live storage capacity at EL.1680 ft.	6911 million cum (5.60 MAF)
Gross storage capacity at EL.1680 ft.	9340 million cum (7.57 MAF)
Dead storage capacity	2430 million cum (1.97 MAF)

Bhakra Power Plant

Number of power houses	2
Installed capacity of left bank power plant	450 MW - 5 units of 90 MW each
Increased capacity of left bank power plant by uprating the machines.	540 MW - 5 units of 108 MW each
Installed capacity of right bank power plant.	600 MW - 5 units of 120 MW each
Increased capacity of right bank power plant	Uprated to 660 MW - 5 units of 132 MW each
Present capacity by further uprating the machines.	735 MW - 3 units of 157 MW each & 2 units of 132 MW each
Planned uprated capacity.	785 MW - 5 units of 157 MW.

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Nangal Dam

Nangal Dam situated about 13 Kms. Downstream of Bhakra Dam, is 29m (95 ft.) high & comprises 26 bays of 9.14m (30 ft.) each. It is designed to pass a flood 9910 cumecs (350000 cusecs) water. Dam diverts the water of river Sutlej into Nangal Hydel Channel & Anandpur Sahib Hydel Channel for power generation and irrigation purpose. Nangal Pond acts as a balancing reservoir to smoothen out the diurnal variation in releases from the Bhakra Power Plants. Nangal Hydel Channel is a lined channel taking off from the left bank of river Sutlej just above the Nangal Dam. The natural fall available along the channel is utilised at Ganguwal and Kotla for generating power. Anandpur Saheb Hydel Channel takes off from nangal Barrage and along the left bank of river Sutlej almost parallel to and on the left side of the Nangal Hydel Channel. It is 33 Kms. Long with a discharging capacity of 10150 Cs. It has two power houses at Ganguwal and at Kotla.

Salient Features

Height	29 meters (95 ft.)
Length	304.8 meters (1000 ft.)
Length of Nangal Hydel Channel	64.5 kilometers (40 miles)
Discharge	354 cumecs (12500 cusecs)
Number of power houses	2
Total installed capacity of each power house.	77 MW (2units of 24 MW each & one unit of 29 MW)
Head of water	28.35 meters (93 ft.)

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Pandoh Dam

Pandoh Dam is a diversion dam of the River Beas at Pandoh situated about 21 Kms. Upstream of town of Mandi in Himachal Pradesh on Mandi Kullu Road. It is a zoned earth-cum-rockfill dam 76.20m(250 ft.)high above the deepest foundation. A chute spillway with flip bucket for maximum design outflow of 350000 cs. has been provided on left abutment. There are five bays in which high pressure top seal type radial gates have been installed for regulating flow of water. Each gate is independently operated by 200 tonnes capacity cylindrical hydraulic hoists.

Salient Features

Type of dam	Earth-cum-rockfill
Height above river bed	61 meters (200 ft.)
Height above deepest foundation	76.2 meters (250 ft.)
Elevation at top of dam	EL.899.16 meters (EL.2950 ft.)
Length at top	255 meters (835 ft.)
Width at base.	268.22 meters (880 ft.)
Width at top	12.19 meters (40 ft.)
Maximum reservoir level	EL.896.42 meters (EL.2941 ft.)
Normal reservoir level	EL.883.92 meters (EL.2900 ft.)
Minimum reservoir level	EL.883.92 meters (EL.2900 ft.)
Gross storage capacity	4100 hectare meters (33240 acre ft.)
Live storage capacity at EL.2941 ft.	1855.98 hectare meters (15.039 acre ft.)
Spillway Type	Orifice type gates chute
Radial gates	5 No. 12m x 13m (39.375 ft. x 42.65 ft.) each
Maximum outflow	9939 cumecs (351000 cusecs)
Crest elevation	EL. 874.78 meters (EL.2870 ft.)

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Pong Dam

Pong Dam was primarily envisaged for meeting the irrigation water requirements of Rajasthan, Punjab and Haryana. But presently, it is being used for power generation too. The Dam is located at Pong across river Beas in Kangra district of Himachal Pradesh. It is the highest earth fill Dam so far constructed in the country. The number of instruments of different types have been embedded in the body of dam to observe its behaviours. Rajasthan draws its maximum share of water from Pong Dam. Five concrete lined tunnels, were constructed for river diversion during construction satge. After serving their function as diversion tunnels two of these tunnels have been converted into outlets for controlled irrigation releases and the other three are used as penstocks. Each penstock tunnel has been provided with an emergency gate, operated from the hoist structures, located at top of the dam. A chute spillway has been provided for passing the flood which is located on the left abutment of the dam. The spillway caters with maximum discharge of 437000 cs. Water is led to ogee shaped crest through an approach channel and controlled by six number radial gates which are operated by electrically driven mechanical hoists with provision for operation by diesel engines in case of power failure. Pong Power Plant is a reinforced concrete framed structure, located in the stilling basin downstream of penstock tunnels . The power plant has an installed capacity of 360 MW having six units of 60 MW each. Uprating of each unit from 60 MW to 66 MW has been planned.

Salient Features

Type of dam	Earth core gravel shell
Elevation at top of dam	EL. 435. 86 metres (EL. 1430 feet)
Free board (above max. RWL)	2.74 metres (9 feet)
Maximum height of dam above deepest foundation level	132.59 metres (435 feet)
Crest length	1950.7 metres (6400 feet)
Width at crest	13.72 metres (45)
Maximum width at base (excluding toe weights)	610 metres (2000 feet)
Catchment area	12560 sq. kilometres (4850 sq. miles)
Normal reservoir level	EL 426.72 meters (EL 1400 feet)
Dead storage level	EL. 384.05 meters (EL.1260 feet)
Gross storage capacity	8570 million cum. (6.95 MAF)
Live storage capacity	7290 million cum (5.91 MAF)
Maximum reservoir depth	97.84 metres (321 feet)
Maximum reservoir level	EL 433.12 metres (EL 1421 feet)
Reservoir length	41.8 kilometres
Type of spillway	Overflow gated chute
Spillway gates	Six radial gates 14.48 m x 12.344m ( 47.5 ft. x 40.5 ft.) each
Crest elevation	416.05 meters (1365 feet)
Penstock heads	3 Nos, each of 7.28 m dia branched into six penstocks of dia 5.025m each
ype of turbine	Vertical shaft, Francis type
Head variation	47.85 meters to 95.1 meters (157 feet to 312 feet)
Installed capacity	60 MW x6 = 360 MW

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Ranjitsagar Dam

Ranjit Sagar Dam (Thein dam) is a gigantic Multipurpose River valley Project constructed on river Ravi, 24 kms. Upstream of Madhopur Headworks. The construction of Ranjit Sagar Dam is a part of the total plan for the utilization of the water of three eastern rivers namely Sutlej, Beas and Ravi for irrigation and Power generation. Ranjit Sagar Dam is located in a gorge section of river Ravi near village. Thein in J&K state, in seismically active zone of Himalayas constituting the Shivalik range. The Project is an embodiment of inter state relationship and co-operation amongst the States of Punjab, J&K and Himachal Pradesh. An inter state agreement between these States was signed in 1979 thereby giving the go-ahead for the execution of the Project.

Unique Features

• The Ranjit Sagar Dam is the highest earth core-cum-gravel shell dam in India.
  * The Power Plant has the second biggest Hydro-Turbine in India.
  * The Project has the largest dia. Penstock in India.
  * The foundation gallary under the Rockfill Dam has been provided for the first time in India.

Salient Features Of The Project

Catchment area	6086 sq. km
Reservoir area	87.00 sq. km.
Gross Storage capacity	3280 million cum
Live storage capacity	2344 million cum

Dam Type	Earth core-cum-gravel shell dam
Top level of the Dam	EL 540.00 m
Maximum height of dam	160.00 m.
Length at Top of the dam	617.00 m.
Width at top of the dam	14.00 m
Maximum width at base of the dam	669.2 m
Normal reservoir level	527.91 m.

Clear water-way of spillway	109 m.
Crest level of spillway	EL 511 .7 m.
Maximum outflow	24637 cumecs
Spillway design flood	20678 cumecs

No. of Penstock Headers	2
N0. of Penstock Branches	4
Dia of each Penstock Header	8.5 m.
Dia of each Penstock Branches	5.17 m.

Type of turbines	Vertical Shaft Francis
Maximum net head	121.9 m.
Minimum net head	76.0 m.

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Upper Indravati HE Project (Orissa)

Upper Indravati Hydro Electric Project has gone fully operational during 2001 with the commissioning of Unit No.IV of the 600 MW (150 x 4) Hydro Power Project. Started with World Bank assistance, Upper Indravati Project is considered one of the largest multi-purpose projects in India. Situated in drought prone districts of Kalahandi and Nawarangpur in Orissa, the project also envisages trans-basin diversion of water of river Indravati (Godavari basin) to river Hati (Mahanadi basin).

The project provides irrigation to more than one lakh hectres of land. The Upper Indravati Project envisages diversion of water , of the indravati river in its upper reaches into the Mahanadi valley for power generation and irrigation. The project involves construction of 4 dams across the Indravati and its tributaries 8 dykes and two inter-linking channels to from a single reservoir with a live capacity of 1435.5 Mcum, 4.32 km. tunnel, a power house with installation of 4 units of 150 MW each , 9 km. tail race channel and an irrigation barrage across Hati river with the associated irrigation canals. It is not only one of the largest power stations in the entire region and will play a crucial role in bridging the projected deficit during peak hours.

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Nathpa Jhakri HE Project

Nathpa Jhakri Hydro-electric Project – NJHEP, is located in the state of Himachal Pradesh, on the downstream of Wangtoo Bridge and derives its name from the names of two villages in the Project vicinity - Nathpa in district Kinnaur and Jhakri in district Shimla - in the interiors of Himachal Pradesh. The Project was conceived as a run-of-river type hydro power development, harnessing hydro-electric potential of the middle reaches of the river Sutlej, one of the principal tributaries of the river Indus, in the south west Himalayas. The Project's Dam has been constructed near village Nathpa and its Power House has been constructed on the left bank of the river Satluj at village Jhakri. The power house site is about 150 km from Shimla. The Project stretches over a length of about 50 kms. from the Dam site to the Power House site, on the Hindustan-Tibet Road (NH-22), which also connects the rail head to the Project. Salient Features The project with an installed capacity of 1500 MW ( 6 X 250 MW ), envisaged construction of the following major components :

• * A 62.50 m. high concrete Dam on Satluj river at Nathpa to divert 486 cumecs of water through four Intakes.
• * An underground De-silting Complex, comprising four chambers, each 525 m. long, 16.31 m. wide and 27.5 m. deep, which is one of the largest underground complex for the generation of hydro - power in the World.
• * A 10.15 dia. and 27.394 km. long Head Race Tunnel, which is one of the longest hydro power tunnels in the World, terminating in a 21.60 m / 10.20 m dia and 301m deep Surge Shaft.
• * Three circular steel lined Pressure Shafts, each of 4.90 m dia and 571 m to 622 m length, each bifurcating into two near the Power House, to feed six generating units.
• * An underground Power House with a cavern size of 222 m x 20 m x 49 m having six Francis Turbine Units of 250 MW each, to utilize a design discharge of 405 cumecs and a design head of 428 m.
• * 6 nos. vertical axis Francis turbines Generating Units, each of 250 MW, with the total installed capacity as 1500 MW.
• * A 10.15 m dia and 982 m long Tail Race Tunnel to discharge the water back into the river Satluj.
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Sardar Sarovar

The Sardar Sarovar dam is a concrete gravity dam, 1210 meters (3970 feet) in length and with a maximum height of 163 meters above the deepest foundation level, is under construction across river Narmada. The dam will be the third highest concrete dam (163 meters) in India, the first two being Bhakra (226 metres) in Himachal Pradesh and Lakhwar (192 meters) in Uttar Pradesh. In terms of the volume of concrete involved for gravity dams, this dam will be ranking as the second largest in the world with an aggregate volume of 6.82 million cu.m. only behind Grand Coule Dam in USA with a total volume of 8.0 million cu.m. This dam with its spillway discharging capacity of 87,000 cumecs (30.70 lac), will be the third in the world after Gazenba (1.13 lac cumecs) in China and Tucurri (1.0 lac cumecs) in Brazil.

Canals:

Narmada Main Canal, which is a contour canal, is the biggest lined irrigation canal in the world. It is about 458 km. long up to Gujarat -Rajasthan border having discharging capacity 1133 cumecs (40000 cusecs) at its head tapering to 95.70 cumecs (3375 cusecs) at the Gujarat -Rajasthan border. The canal extends further in Rajasthan to irrigate areas in Barmer and Jhalore districts of Rajasthan. The cross section of the canal at its head is 73.1m x 7.6m (Bed width x Full supply depth) with 2:1 inner side slope having canal velocity at head as 1.69 m/sec. The entire length of the Main Canal is proposed to be lined with in-situ plain cement concrete to minimize seepage losses, to allow higher velocities and control water logging problems in future. In all, there are 593 Structures on the Narmada Main canal. Out of this 320 structures are cross drainage structures, comprising of 5 Aqueducts, 15 canal syphons, 177 drainage syphons, 26 canal crossing and one super passage. There are 96 Regulating structures comprising of 1 Main HR, 44 Branch HR, 38 Cross Regulators and 13 Escapes. There are total 273 nos. of Road Bridge including national Highway, State Highway, MDRB, ODRB, VRB, and UVRB etc. Narmada Main Canal as on today is almost completed up to 357 km. and water has flown through it.

Power Houses

There are two power houses for the Sardar Sarovar Project (SSP). (i) 1200 MW River Bed Power House (RBPH) and (ii) 250 MW Canal Head Power House (CHPH). Power benefits are shared among Madhya Pradesh, Maharashtra and Gujarat in the ratio of 57:27:16 respectively. The RBPH is an under ground power house stationed on the right bank of the river located about 165 meters downstream of the dam. It has six number of Francis type reversible turbine generators each of 200 MW installed capacity. These units can operate at minimum reservoir water level of 110.64 meters. The generation of power depends upon inflow of water from upstream projects and need of water for irrigation in Gujarat. The CHPH is a surface power station in a saddle dam on right bank of the reservoir having total installed capacity of 250 MW (5 x 50 MW). These five units have been commissioned in a phased manner during Aug-04 to Dec-04. These units can be operated with minimum reservoir water level of 110.18 meters. The CHPH is being operated in consultation and as per advice of NCA/WREB based on irrigation requirement of Gujarat/Rajasthan and availability of water in reservoir and release from upstream project of Madhya Pradesh.

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