Rubber Dam, an Alternate to Gravity Dam for Reservoir Submersion Issues - a Case Study
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Rubber Dam, An Alternate to Gravity Dam for Reservoir Submersion Issues - A case Study. Dr. I Satyanarayana Raju, MTech,MBA,Mphil,BL,FIE,PhD, Former Chief Engineer,CDO(WRD) & Expert, State Dam Safety Inspection Team & Member TAC-WRD,GoAP; Imm Past Chairman, IEI, Telangana State centre & Past Chairman IEI, AP State Centre,Hyderabad-500082(TS). Contact:[email protected]; +91 9676686158 WELCOME TO Dignitories,Invited Speakers,Technical Paper Presenters,Delegates&Organisors, Of International Conference On “Recent Trends in Civil Engineering and Water Resource Engineering” RTCWRE-2017 By Dept.of Civil Engineering Holy Marry Institute of Technology & Science(JNTUH Affliated) Hyderabad, Telangana State. Presntation… Contains • Preamble • Water in India • Issues of Major Dams • Case Study-Janjavathi Rubber Dam • A few existing Rubber Dams Globally • Conclusions Preamble • Water is called ‘JIVANAM” in Sanskrit which means it is a way of life. • Water is a natural and renewable resource ,can be exploited for sustenance of world and to the benefit of society at large. • Water is not only meant for sustenance of life but also for development of civilization, culture, food production, and of economy growth of the Nation and world at large. • It is a general feeling that water is abundant and freely available all the time to everybody. • Fresh water available in universe is only 2.53%. • Of which 1.53% is only locked up in Glaciers. • Ultimately 1% left for human consumption. Water In India ➢ India’s land resource is 2.45 % of that of World’s ➢ India has only 4 % of the world’s water resource but supporting 17 % of the World’s population. ➢ 76 % of the total precipitation occurs in just 4 months, some times even 50 % of the precipitation occurs in just 15 days and <100 hrs. ➢ Of the 4000 BCM annual precipitation, 3000 BCM occurs during monsoon months(4). ➢ Average annual flow is 1953 BCM but 1122 BCM is utilizable. 8 Position of India in world scenario • Land Resources ----------- 2.45% • Renewable Water Resources - 4% • Population ----------------- 17% 9 Water in India Total Precipitation 4000 BCM Total water availability 1869 BCM Total utilizable water resources 1123 BCM Surface water Ground Water 690 BCM 433 BCM Current utilization Current utilization 450 BCM ( 65% ) 243 BCM (58%) 10 Annual Average Rainfall Rainfall in mm Average 1,170 Mawsynram, Max. 11,000 Meghalaya Min. 100 Western Rajasthan 11 Water Resources in India 12 Water Availability Per Capita in Cum. 13 WATER STRESS ❑ As per existing water resources per capita availability of water varies from 300 to 13754 (Cum) ❑ National annual average per capita availability in 2001 is 1829 Cum ❑ By 2021 this national average is expected to reach 1557 Cum ( Water Stress) ❑ By 2050 it may further reduce to 1168 Cum 14 Ground Water Status ❖Ground Water Resources - 431.9 Km3 ❖Natural recharge from rainfall - 342.4 Km 3 ❖Recharge from canal irrigation system -89.5 Km3 ❖Ground water accounts for 45 % of the total Irrigation 15 Storage Capacity in Dams of India (BCM) Large Dams in India – 4857 Nos. 16 17 Water use priority 1.Drinking water 2.Irrigation water 3.Hydro power 4.Ecology 5. Agro-industries and non-agricultural industries. 6. Navigation and other uses . Projected Water Demand In India by 2050 19 Future demands of water 20 ) 3 Water Demand in BCM (km Year Scenario of Irrigation development in India • Geographical Area 328.73 Mha • Total Cultivable Land: 181.98 Mha • Ultimate Irrigation Potential: 139.89 Mha • Potential Created (as available Statistics): 113.53 Mha • Major & Medium: 47.97 Mha • Minor: 65.56 Mha • Gross Sown Area: 195.25 Mha • Gross Irrigated Area: 91.53 Mha • Net Sown Area: 140.80 Mha • Net Irrigated Area: 65.26 Mha • Rainfed cultivated Area 86.42 Mha 21 Actions to be Initiated for Water Conservation • Water Availability • Per Capita Availability – 1545 Cum against stress condition being 1700 Cum • Irrigation Development • 113 Mha. potential created against ultimate potential of 140 Mha • 88 Mha potential utilised against 113 Mha created potential • Storage Creation • Creation of 253 BCM Storage against desired potential of 450 BCM • Efficiency in Irrigation • Surface Water – presently at about 40% against possibility of 60% • Ground Water – presently at about 70% against possibility of 75% 22 Issues Related to Conceiving Major Dams • The states could construct Gigantic dams like Bhakra-Nangal, Hirakhud,Srisailam,Nagarjuna-Sagar etc. as Land Acquisition (LA) is very much within regulatory control of respective Governments • Only financial compensation used to be paid to land and habitation losers. • But in present scenario, Land Acquisition and R&R are major constraints in taking up any new Dam. • The Rehabilitation and Resettlement (R&R) has become a major issue for conceiving and completing new Dams under prevailing LA & RR Acts in India. • The Land Acquisition (LA) for the submergible lands of larger extents under dams including land required for Dam construction. • LA Process is very critical and a delayed process to take up any Dam in Indian democratic Scenario. • The implementation of provisions of latest R&R and LA Acts have become cumbersome and time consuming. • The Interstate River Basin issues for implementing Dams by respective states in India either as joint project or in individual states stands unresolved for decades together. A Case Study-Janjavati Irrigation Project, Andhra Pradesh (AP) • Jhanjavati Reservoir ,a Medium Irrigation Project was taken up by Andhra Pradesh way back in 1976 at an estimated cost of Rs.15.15 crores to benefit 10,000,Ha in most backward region of Vizianagaram dist of North Coast. • Classification of Projects:Major Project(>10000,Ha.); Medium Project (2000Ha-10000Ha);Minor(<2000Ha) • The Janjhavathi Reservoir Project situated across Janjhavatjhi River, a tributary of Nagavali River near Rajyalaxmipuram (V) Komarada Mandal of Vizianagaram District of AP to benefit 75 villages, bordering to Odisha State. • Janjavati Scheme was an Interstate Project since River originates in Odisha State and Project was conceived in State of AP. • An Inter State Agreement was entered into between State of Andhra Pradesh and Odisha Government for Utilizing 50% of yield i.e., 4TMC of water in the Year during 1976-78 after series of meetings between two States. • It was further agreed to carry out the project works except in river gap portion ( River Gorge) until amicable settlement of land acquisition to the extent of submersion lying in Odisha territory in the fore shore of Dam. LOCATION MAP OF JANJHAVATHI RUBBER DAM ANDHRA PRADESH JANJHAVATHI RIVER RUBBER DAM Dam Salient Features • Catchment area…………………………….325 Sq.Miles. • Max. Flood Discharge……………………..2,18,953 Cusecs. • Gross storage Capacity……………………3.40TMC. • Live Storage………………………………….2.774TMC. • F.R.L……………………………………………+146.20M. • MWL…………………………………………….+146.20M. • Free Board……………………………………..3.00M. • Spill Way Length……………………………..89.50M. • Spillway Gates……………………………6Nos.-12MX11M(Radial). • Dam Length……………………………………4.07Km. • NOF…………………………………………….154M. • Rubber Dam crest………………………… +122.50M. • Height of Rubber Dam………………………03.2M. • Lift Height for Canal Pump with Rubber Dam-17M; • Pumps-3Nosof 650HP. A Case Study-Janjavati Irrigation Project, Andhra Pradesh • The submergible issue in Odisha state territory stands unresolved as on the date even after lapse of 4 decades • The project came to standstill for want of closure of River Gap,and left over balance work since 40 years. • The Odisha state is not agreeing for the financial compensation extended by State of A.P and also not accepting in toto cost towards the R&R package to be decided by Odisha state. • The reasons are political, which Odisha ruling party feels to have an impact on Vote bank, issues likely to raised by Opposition Parties of that State. • As a result the Project investment made as of date has become in-fructuous and about 10000 ha. ayacut getting starved for non-completion of Dam even after 40 years of its commencement. • The balance cost of project works now inflated to an order of Rs.150 crores at current schedule of rates. • No solution is emerging for completion of Dam in near future due to delay of R&R issue in the state of Odisha. The Way Forward • The Irrigation experts of Water Resources Department of Andhra Pradesh interacted with Global technocrats. • A Technical solution by proposing a Rubber Dam of 3.2 M height in the River Gap was evolved for immediate benefit of 10000 Ha of Irrigation. • When once,Inter state Issue with Odisha settles, the original proposed can be permanently raised in the River Gorge portion to its Full Reservoir Level (FRL) originally contemplated with storage facility of 2TMC. • This Rubber Dam is a diversion arrangement in River Gap and avoid submersion in Odisha territory with facility of deflation at the time of floods and can be inflated to a height of 3.2M in normal lean flows of Janjavathi River. • By this arrangement, partial gravity Irrigation and lift irrigation (Head of -17M) benefit 10000 Ha. • After original dam completion in river Gorge,the rubber Dam can redeployed elsewhere for similar purpose. Rubber Dam • Inflated Rubber dams are cylindrical rubber fabrics placed across channels, streams and weir or Dam crests to raise the upstream water level when inflated. • The membrane is a multi-layer fabric made of synthetic fiber (Usually Nylon) and rubberized on one or both sides. • The fabric is quite flexible and yet exhibits good wear resistance characteristics. • A layer of stainless steel mesh or ceramic chips can be embedded in the surface layer to reduce or prevent vandal damage. • The Technology was developed in early 1950s. • They are installed in stream and river beds, generally being bolted into a concrete foundation and used to divert water for irrigation, temporarily raising existing dams, flood control, water retention for aquifer recharge. • They also used for reducing or preventing salt water intrusion in to fresh water areas, protecting low lying coastal areas from tidal flooding, enabling fish passage over diversion works, by deflation, and for sewage retention/separation during flood events.