A REPORT ON VISIT AT SARDAR SROVAR DAM. Faculty : Asst. Prof. Bhargav V. Vadalia MECHANICAL ENGINEERING DEPARTMENT OM ENGINEERING COLLEGE, JUNAGADH.

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1 A REPORT ON VISIT AT SARDAR SROVAR DAM Date of Visit : 11th Sept., 2015 Branch : MECHANICAL Time : 08:00 am 03:30 pm Semester : 5th Faculty : Asst. Prof. Bhargav V. Vadalia MECHANICAL ENGINEERING DEPARTMENT OM ENGINEERING COLLEGE, JUNAGADH.

2 1. HISTORY The plan for harnessing the river for irrigation and power generation in the Narmada basin was initiated in Seven projects including the Bharuch project were identified during the initial Survey and 4 projects Bharuch (Gujarat), Bargi, Tawa and Punasa in Madhya Pradesh were given top priority for investigation. After the completion of investigation, the proposed dam at Gora in Gujarat with the full reservoir level (FRL) 161 ft (49.08m) was selected and the foundation stone was laid by late Prime Minister, Pandit Jawaharlal Nehru on 5th April, However as more detailed, modernised contour sheets from the Survey of India were available thereafter, possibility of raising the height of the dam for optimum utilisation of water was considered. In 1964, to resolve the dispute about sharing of the Narmada Waters between the Governments of Gujarat and Madhya Pradesh, the Government of India appointed an expert committee under the Chairmanship of late Dr. Khosla which recommended a higher dam with FRL 500 ft (152.44m) in However, Govt. of M.P. was not agreeable to development of Narmada water as per Khosla Committee report and hence the Narmada Water Dispute Tribunal (NWDT) was constituted by the Government of India in October 1969, under the Inter State River Water Disputes Act, NWDT gave its final award in December 1979.

3 2. BENEFITS OF PROJECT a) Irrigation The Sardar Sarovar Project will provide irrigation facilities to lac ha. of land, covering 3112 villages of 73 talukas in 15 districts of Gujarat. It will also irrigate 2,46,000 ha. of land in the strategic desert districts of Barmer and Jallore in Rajasthan and 37,500 ha. in the tribal hilly tract of Maharashtra through lift. About 75% of the command area in Gujarat is drought prone while entire command in Rajasthan is drought prone. Assured water supply will soon make this area drought proof. b) Drinking water supply A special allocation of 0.86 MAF of water has been made to provide drinking water to 131 urban centres and 9633 villages (53% of total villages of Gujarat) within and out-side command in Gujarat for present population of 28 million and prospective population of over 40 million by the year All the villages and urban centres of arid region of Saurashtra and Kachchh and all "no source" villages and the villages affected by salinity and fluoride in North Gujarat will be benefited. Water supply requirement of several industries will also be met from the project giving a boost to all-round production c) Power There are two power houses viz. River Bed Power House and Canal Head Power House with an installed capacity of 1200 MW and 250 MW respectively. The power would be shared by three states - Madhya Pradesh - 57%, Maharashtra - 27% and Gujarat 16%. This will provide a useful peaking power to western grid of the country which has very limited hydel power production at present. A series of micro hydel power stations are also planned on the branch canals where convenient falls are available.

4 d) Flood Protection It will also provide flood protection to riverine reaches measuring 30,000 ha. covering 210 villages and Bharuch city and a population of 4.0 lac in Gujarat. e) Wild Life Wild life sanctuaries viz. "Shoolpaneshewar wild life sanctuary" on left Bank, Wild Ass Sanctuary in little Rann of Kachchh, Black Buck National Park at Velavadar, Great Indian Bustard Sanctuary in Kachchh, Nal Sarovar Bird Sanctuary and Alia Bet at the mouth of River will be benefited. f) Additional Production SSP would generate electricity. On completion, annual additional agricultural production would be Rs crores, power generation and water supply Rs. 175 crores, aggregating about Rs crores every year equivalent to about Rs. 6.0 crores a day. g) Against one tribal displaced, 7 tribals would get benefits In addition, there will be benefits of fisheries development, recreational facilities, water supply for industries, agro industrial development, protection of conserved forest from grazers and secondary benefits viz employment generation, increase in vegetal cover in 3.4 M. Ham. of GCA, gains due to compensatory forest, tree plantation 100 times and Carbon Dioxide (CO2) fixation to large extent by 70 times. h) Other Benefits Marginal farmers (< 1 ha.) 28.0 Small farmers (1 to 2 ha.) 24.4% Scheduled Tribe 8.7% Scheduled Caste 9.1% 3. COMPONENTS OF PROJECT a) Sardar Sarovar Reservoir The Full Reservoir Level (FRL) of the Sardar Sarovar Dam is fixed at RL metres (455 feet). The Maximum Water Level is metres (460 feet.) while minimum draw down level is metres (363 feet.). The normal tail water level is metres (85 feet.). The gross storage capacity of the reservoir is 0.95 M. ha.m. (7.7 MAF) while live storage capacity is 0.58 M.ha.m. (4.75 MAF). The dead storage capacity below minimum draw down level is 0.37 M. ha. m. (2.97 MAF). The reservoir would occupy an area of 37,000 ha. and would have a linear stretch of 214 kilometer of water and an average width of 1.77 kilometer.

5 The submergence at Full Reservoir LCanal Head Power Houseevel (FRL) is 37,690 ha. (86,088 acres), which comprises 11,279 ha. agricultural land, 13,542 ha. forests and 12,869 ha. river bed and waste land. In all 245 villages of the three states viz. 193 Villages of Madhya Pradesh, 33 villages of Maharashtra and 19 villages of Gujarat are affected. Only 3 villages of Gujarat are fully affected, while the remaining 16 villages are partly affected. In Madhya Pradesh, out of 193 villages, more than 10% agricultural land will be submerged only in 79 villages, in 89 villages less than 10% agricultural land or only houses will be submerged under FRL, due to back water of 1 in 100 years flood. In 25 villages, only Government waste land will be submerged. b) Sardar Sarovar Dam 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. The first is Grand Coule Dam in USA with a total volume of 8.0 million cu.m. This dam with its spillway discharging capacity of 85,000 cumecs (30.00 lac), will be the third in the world, Gazenba (1.13 lac cumecs) in China and Tucurri (1.0 lac cumecs) in Brazil being the first two. For chute spillway Radial gates, 7 in number and size 60' x 60' and for service spillway, 23 Radial gates of size 60' x 55' are to be provided to negotiate the design flood. 10 number of temporary construction sluices, each of size 2.15 m x 2.75 m. are provided in the boby of the spillway at RL 18 m. Another set of 4 permanent river sluices are provided at RL 53.0 m. The lower sluices were closed in February, The design of the dam allows for a horizontal seismic coefficient of 0.125g and it also covers an additional risk due to reservoir induced seism city. Most sophisticated seismological instruments for monitoring and evaluation of the stresses in the body of the dam as well as the effect on the periphery of the reservoir are under installation. c) Hydro Power I. River Bed Power House 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. The T.G. Sets are supplied by M/S Sumitomo Corporation, Japan and M/S BHEL. These units can operate at minimum reservoir water level of meters. These six units have been commissioned in a phase manner during Feb-05 to June-06. The generation of energy depends upon inflow of water from upstream projects and need of water for irrigation in Gujarat.

6 II. Canal Head Power House 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 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. The energy generated from both the power houses is to be evacuated through 400 KV level through interconnecting transformers at GIS, situated in RBPH switch yard. The 400 KV Switchyard is indoor type having Gas Insulated Switch Gear and Bus bars. The energy is transmitted to party states i.e. Gujarat, Maharashtra and Madhya Pradesh in the proportion of 16:27:57 respectively through 400 KV double circuit transmission lines, namely SSP-Kasor, SSP-Asoj, SSP-Dhule and SSP-Nagda respectively. All the transmission lines are commissioned and charged. The operation and maintenance of SSP power complex and transmission lines is being done by Gujarat State Electricity Company Limited (GSECL), for which O&M agreement between SSNNL and GSECL has been signed. III.Small/Mini/Micro Hydro Power Project The Development of Small/Mini/Micro Hydro Power Projects on Sabarmati escape NMC chainage 229 km & Narmada Dam Godbole Gate at Kevadia Colony is not feasible due to following reasons: At the ultimate stage of project development, there will not be surplus water to the released through such Escapes and data of past can not be considered for future projection in such cases. A guaranteed/assured discharge through Escapes, power generation can not be predicted and therefore its economic viability is questionable. Godbole Gate essentially is a device to discharge surplus water back to the River and not to the Head Regulator of the canal. This arrangement under ideal normal conditions will not be functional and any investment made on such contingent would not guarantee the investor any dependable return.

7 The Godbole Gate will not be operated all time, but the quantum will also be determined by levels in the ponds and would continue to fluctuate with water level in Pond no. 3 & 4. this would also seriously affect power generation as quantum and velocity of water vary greatly. Hydro Power requires a definite discharge and velocity. Hence investment made on such contingent arrangement would not guarantee the investor and dependable return. d) Main Canal Narmada Main Canal is a contour canal. It is the biggest lined irrigation canal in the world. It is about km. long up to Gujarat -Rajasthan border. The canal extends further in the state of Rajasthan to irrigate areas in Barmer and Jhalore districts of Rajasthan. The Main Canal is lined with plain cement concrete to minimise seepage losses to attain higher velocity and to control the water logging in future. The lining work is carried out with the mechanized pavers. Such a large scale paving of concrete lining is done for the first time in India. The Main Canal in its journey has to negotiate several water streams, rivers, roads, railways etc. This is possible by constructing appropriate structure on the canal. In all, there are 634 structures on the Narmada Main Canal. Narmada Main Canal as on today is completed up to 458 Km. and water has been flowing throught it right upto the state of Rajasthan. 4. FEATURES OF NARMADA MAIN CANAL Full supply level (F.S.L.) at H.R m (300 ft) Length up to Gujarat - Rajasthan border Km Base width in head reach m Full supply depth (F.S.D.) in head reach 7.60 m Design discharge capacity In head reach 1133 cusec (40,000 cusecs) At Gujarat Rajasthan border cusecs (2,600 cusecs) 5. CANAL DISTRIBUTION SYSTEMS AND THEIR OPERATIONS Number of Branches 38 Nos. Length of Distribution System Network Km. Culturable Command Area Lakh Ha. Water for irrigation will be conveyed to 8 ha. Blocks through a km. network of conveyance and distribution system consisting of branch canals, distributaries, minors and sub-minors. There will be 38 branch canals off-taking from main canal, out of whichmiyagam, Vadodara, Saurashtra and Kachchh branch canals will be the major branches having a capacity of more than 75 cumecs (2650 cusecs). The distribution system would cover culturable command area of lakh ha. (45.57 lakh acres) spread over in 3112 villages in 73 talukas of 15 districts of Gujarat. The branch canals and the distribution system network up to 8 ha. Block will be lined. The Canal Systems up to the village levels (called village Service Area) will be operated by

8 the Central Authority i.e. Sardar Sarovar Narmada Nigam Ltd. Below the village levels, the systems will be fully operated by the organizations of farmers to be explicitly formed for the purpose. With the system affixed annual water allowance pre-decided and pre declared for various parts of the command area, is easy to convert this water allowance into numbers of actual watering that the farmers would get from the system at the village levels. For example, on an average about 6 to 7 annual watering can be made available to the farmer s Associations at village levels. It is the need-based privilege of the farmers associations to plan what number of watering that they would like to avail in the Kharif (monsoon) season and what number of watering they would like to use in the non-monsoon (winter)season. They would take decisions on the basis of rainfall an its distribution. Once the farmers make their schedules, it would be easy to aggregate these at the level of distributaries and branches of the systems. Command Area Development Sardar Sarovar (Narmada) Project (SSP covers Culturable Command Area (CCA) of lac ha within Gujarat. With extensive studies on the subject, detailed elaborate and micro level plan has been evolved to deal with the development of SSP command. Entire command area is divided into 13 agro climatic zones and each zone is further subdivided in to irrigation and drainage blocks ranging from 4000 to 10,000 ha. Involvement of farmers in the construction activities and there after for irrigation management is aimed at to ensure efficient user friendly uses. The system below the VSA outlets will be managed by the Water Users' Associations (WUAs) based on Participatory Irrigation Management (PIM). One of the unique feature is that the Irrigation Water in the command area of SSP would be delivered to farmer's groups (Water Users Association (WUA) and not to individual farmers. It would be for the farmers groups to manage distribution within their block called village service Area (VSA). The corollary to this management is that the minors, subminors and field channels will be owned and looked after by these WUAs. Involvement of farmers/ngos in the construction of micro level canal network system would ensure 'owners' amongst the beneficiary farmers. A suitable system called Rotational Water Supply (RWS) - Varabandhi would be implemented to ensure timely, and assured and equitable supplies. The another important feature is the volumetric supply of water instead of conventional area approach. The micro level canal systems with appropriate structures are being designed and constructed to ensure timely and equitable distribution of water. This would guard against the most commonly observed problem of overuse of water by initial command blocks, leaving less supplies to the tail enders. To ensure efficient water uses, the evaluation would be based on delta basis. Water intense crops would be discouraged. Micro irrigation system like drip and sprinkler would be encouraged for efficient water uses. An interesting as well as innovative feature of the SSP's irrigation plan is to supplement canal water supply by conjunctive use of ground water. This would augment total water availability and stretch the irrigation benefit to more area. It will also prevent water logging by regarding excess ground water and thereby protecting command against water logging and soil salinity.

9 6. CURRENT STATUS a) BRIEF DESCRIPTION PROJECT 1. Irrigation Sardar Sarovar Project Benefits : 1.84 Mha (75% area drought prone) in Gujarat. : Mha in desert districts of Rajasthan 2. Drinking Water : 25 Milion Population (by 2011) : 30 Milion Population (by 2021) : 9490 Villages Urban centers in Gujarat : 1336 villages & 3 towns in Rajasthan to a population of approx million 3. Hydro Power : Installed capacity : 1450MW 4. Irrigation Strategy : Through RWS & PIM, maximum water use efficiency can be achieved. Water hazards due to over watering salinity and water logging can be prevented leading to sustainable agricultural benefits to small and marginal farmers in the command area. b) PROGRESS OF MAJOR COMPONENT OF THE PROJECT MAIN DAM The work of raising of dam up to mt. is completed. The Narmada Control Authority has given the permission on to raise the Dam height from m to m for Phase-1 construction i.e. to raise piers up to full height, construction of bridge and installation of gates (to be kept in open position). The work has been started on and the same will be completed within 36 months LCM [97.39%] concrete work completed up to March Construction of Irrigation Bye Pass Tunnel is completed. Garudeshwar Weir : Excavation has been started and work of Coffer Dam is in progress. The progress of Excavation is m3 up to March-2015

10 Power Generation Particular Unit Upto Mar2014 Mar-2015 During upto Mar-2015 Total RBPH (River Bed Power House) Million Units CHPH (Canal Head Power House) Million Units Total (A & B) Million Units Progress of Canal System & Irrigation Potential Created Sr. No Particular Unit Total Upto Mar2014 March2015 During Total (I) Canal System A Main Canal Km Completed B Branch Canal Km C Distributary Km D Minor Km E Sub-Minor Km Total: Km (II) Irrigation Potential (A) Up to Minor Ha (B) Up to Sub-Minor Ha c) NOTE ON SOCIAL AND ECONOMIC DEVELOPMENT Name of State Nos. of affected Total PAFs Likely to Villages be resettled Total PAFs resettled in Balance PAFs to be resettled in Gujarat Maharashtra Madhya Pradesh Total:

11 d) ENVIRONMENTAL SAFEGUARD MEASURES Catchment Area Treatment works have been completed in the entire catchment area (29157 Ha) within Gujarat. Compensatory afforestation has been carried out in 4650 hectares of non-forest area in kachahh district as well as 9300 ha degtaded forest area. Plantation in 5252 hectares has been completed in the vicinity of the dam, on canal banks nad in the colonies lacs Indian Major Carps & Macrobracium Rosenbergii fingerlings have been stocked in the reservoir and dykes. This includes 2.84 lacks Macrobrachium rosenbergii stocket in dykes. The temples of Hamfeshwar and Shoolpaneshwer relocated to higher elevations.