Wshop Int. Riv. Bas. (Dec 2004), Jour. Engg. Geol. (ISEG), Vol. XXXI, No. 1-4, Dec 2004

River linking projects-national perspectives

Jaydip Mukherjee

Introduction 110 million ham against the utilisable water resources of about 116 million ham. Thus it Water is the most essential resource in can be seen that the growth process and every country. is fast moving towards expansion of economic activities inevitably as the average per capita lead to increasing demands for water for water availability will continue to decrease. different purposes. The source of water that Water scarcity increases with population is available in the country is mostly rainfall explosion, expansion of economic activities and snowfall. Combined input is 4000 BCM and rapid urbanisation. The population of from this source, 1869 BCM is available as India is around 1000 million and is hopefully surface and . Considering the expected to stabilise around 1500-1800 water demand scenario of 2050 AD, a million by 2050, that would require about significant deficit is likely. The problem is 400-450 million tonnes of food grains at the rendered more acute by the fact that the present levels of consumption. Therefore, precipitation and consequently the water a production of no less than 500 million availability suffers from nonequitable tonnes is to be achieved by 2050 which distribution. Rainfall varies from less than warrants stepping up of 50 cm in parts of , and development with multiple cropping for areas to more than 200cm increased production. The Central Electrical in eastern part (Ganga-Brahmaputra Basin) Authority has assessed the country’s and West Coast areas. Moreover availability potential as about 84000MW at of water resources in Ganga- Brahmaputra 60% load factor. About 14% of this is Basin is 60% whereas it is only 0.2% in developed so far and the potential that can Sabarmati Basin. Normally water availability be developed from ongoing and planned less than 10OOCM per capita in a river basin projects is about 7%. Thus about 79% of is considered as water scarcity condition. country’s hydropower potential remains still Based on this fact, some basins have untapped. The projected demand of power already become scarce in water, and other by 2050 AD would be 8. 3 million MW and basins are likely to become scarce by 2025. energy of about 44000 billion units. Keeping This situation calls for an efficient water in view the increasing demand for power on management strategy for utmost efficiency domestic and industrial fronts, there is every in and optimum need for tapping of this vast potential. utilisation like control of conveyance and Annual demand of water by 2025 for all evaporation losses, adoption of drip purposes including domestic, irrigation, irrigation methods, interbasin transfers, etc. energy and industrial use would be about Implementation of river linking scheme will

EG DIvn., Geological Survey of India, Samar Vila, Arbuthnot Road, Laitumkhrah, Shillong 793 011 provide some respite from the distressful transfer of water. National water Resources and inequitous situation and remove the Council adopted National water Policy in regional imbalance and water availability in 1987 - which has subsequently been different parts of the country. updated. This National Water Policy rises to the challenges and an issue related to water resources demand in the country and Bakground history enunciates scientifically evolved concept of sustainable water resources management, Interlinking of rivers is not a new concept at and will create balance between drought all. The proposal to link the rivers of North prone deficits and flood ravaging surpluses. India to those of South India is around 150 years old. In 19th century, Sir Arthur Cotton pleaded for interlinking of rivers for National Project components Navigation Plan. The Diversion Project across the Western Ghats to National Water Development Agency Tamilnadu is century’s old examples of (NWDA) has been entrusted to study the interbasin transfer. Moreover, Kurnool - feasibility of the national perspective of the Cuddapah canal in Krishna Basin, Telegu river linking projects. The organisation has Ganga Project for augmenting already identified the links, which could be to Metropolitan areas and Indira implemented based on the numerous water Gandhi Nahar Pariyojana benefiting balance studies for different basins, Rajasthan with the help of , Beas and reservoir sites and link alignments. Field Ravi waters of Indus Basin are few more surveys and investigations for preparation examples. In Sardar Sarovar Project, the of feasibility reports for such identified diversion of Narmada water is being links are currently under progress and proposed to different parts of Gujarat and planned to be completed by 2 0 0 6 . The Rajasthan. Dr. K. L. Rao (1972) envisaged National Perspective Plan has divided the the construction in stages of Ganga- river systems into two broad components: Cauvery Canal, drawing 60000 cumecs of flood flow of Ganga near Patna for about A. Himalayan component 150 days in a year and link up with Cauvery Envisages construction of storage River. Captain Dastur suggested reservoirs on the principal of the construction of garland canal - one for the Ganga and the Brahmaputra in India and Himalayan Watershed and the other for Nepal, along with interlinking of Canal Sayadri (Western Ghat) watershed. These systems to transfer surplus flows to the concepts were not materialised due to eastern tributaries of the Ganga and the certain technical deficiencies. A National Ganga to . It would also provide Perspective Plan (NPP) for water resources the necessary augmentation of flows at development was formulated by the Union Farakka to interalia flush the Kolkata Port Ministry of Water Resources envisaging and the inland navigation facilities across interlinking of rivers by water transfer from the country. The subcomponents are. surplus basins to deficit basins with a view to minimise the regional imbalances and 1. Manas - Sankosh - Tista - Ganga Link. optimally utilise the available water 2. Kosi - Ghagra Link resources in country. Subsequently, 3. Gandak - Ghagra Link National Water Development Agency was 4. Ghagra - Link set up in 1982, which with a view to carryout 5. Sarda - Yamuna Link this plan held studies in respect of interbasin 6. Yamuna - Rajasthan Link 7. Rajasthan • Sabarmati Link 9. Cauvery (Kattalai) Vaigai- GundarLink. 8. Chunar • Sone Barrage Link 10. Ken - Betwa Link. 9. Sone Dam - Southern tributaries of 11. Parbati - Kalisindh - Chambal Link. Ganga 12. Par - Tapi - Narmada Link. 10. Ganga - Damodar-Subarnarekha Link 13. Damanganga - Pinjal Link. 11. Subarnarekha - Mahanadi Link 14. Bedti-VaradaLink. 12. Kosi -Mechi Link 15. Netravati - Hemavati Link. 13. Farakka - Sundarban Link 16. Pamba - Achankovil- Vaippar Link. 14. Brahmaputra - Ganga (Jogighopa - Tista-Farakka Link) Merits and demerits of the scheme

B. Peninsular component The characteristics of interbasin transfer link It envisages construction of storage schemes will be no different than any reservoirs and liversions across river basins conventional irrigation projects. Like having surplus water in peninsular part and conventional project, it will also store the planning for distribution of water surplus to flood/monsoon water of a river basin in the adjacent water deficit basins. Mahanadi and potential storage sites and transfer a part Godavari basins are assessed to have of surplus flood water after meeting all the interlinks to transfer surplus water of inbasin requirement of the area in the Mahanadi and Godavari to the deficit basins. foreseeable future, to deficit areas through Construction of storage structure at potential link canals generally by gravity and lifts not sites, linking of west flowing rivers between exceeding 120m. Basic objectives of the Bombay and Surat (Ken. Betwa, Parbati interbasin transfers are equitable and Chambal) and diversion of other west distribution of available water resources flowing rivers of and within a region or the nation, increased towards the eastern side have been economic efficiency, self sufficiency in basic envisaged. These linkages (2 5 to 2 9 ) water related outputs such as food and besides providing water to the water starved hydroenergy and providing livelihood and areas of Kutch and Saurastra of Gujarat will employment opportunities. Next 50 years in also have plans to provide drinking water to India would witness further accelerated the ever expanding City. The urbanisation. Most of the urbanised areas subcomponents are; would have to depend on surface water from distant reservoirs. On completion of this 1. Mahanadi (Manibhadra) -Godavari project, the following will be coming out; (Dowaiiswaram) Link 2. Godavari - Krishna (Nagarjunsagar Tail 1. Surface irrigation facilities to 25 M ha Pond) Link. land and lOMha by increased use of 3. Godavari (Inchampalli) - Krishna ground water.. (Nagurjan sagar) Link. 2. Generation of 34000MW hydroelectric 4. Godavari (Paiavaram) - Krishna power. (Vijayawada) 3. Delivery of 173 BCM of water. 5. Krishna (Almati)-Pennar Link. 4. Augmentation of dry weather flow in 6. Krishna (Srisailam) - Pennar Link. river channel. 7. Krishna (Nagarjun sagar) - Pennar 5. Employment facilities in agriculture, (Somasila) Link. power, transport and construction 8. Pennar (Somasila) - Cauvery (Grand sectors. Anicut) Link. 6. Regulate uneven into uniform flow condition. 6) Construction of dams in seismotec- 7. Promote inland navigation facilities. tonically active Himalayan region will 8. Promote regional and international co­ cause tectonic imbalance, which may operation. result in earthquake. Moreover, reservoir induced seismicity may Though the megaproject has several develop due to construction of big advantages, the following pitfalls are also reservoirs. noticed: 7) Change in hydrology of river flows coupled with introduction of link 1) Proposed water transfers by their channels and distribution systems will nature are Interbasin and may violate have significant impact on environment. the basic premise of basin as a This project will have significant hydrologic unit for water management. negative role on wildlife habitat and These transfers allow the diversion of result in loss of valuable biological water to the noncobasin states of India. diversity in protected areas. Interiinking Conformity of these proposals may rivers can have very serious impact on need review of existing legal system. territorial distribution system of fishes Moreover, Ganga and Brahmaputra are of India and can show serious negative both international river involving China, impact on its biological cycle due to Bhutan, Nepal and Bangladesh. If one changes in established hydrological of the countres object to the proposal- and limnological profile. Any major it will be difficult for the Indian changes in natural riverine climate are Government to implement the project, likely to affect forest vegetation. and as on today Bangladesh is against Humidity in atmosphere will be the proposal. increased. 2) Water development projects are 8) Chances of leakage and seepage loss normally undertaken by a State besides in long transfer through canal system a few interstate projects by interstate will affect geohydrological setting of the agencies. If in a State particular basin tract. is rich in water resources while an 9) Rise in Ground water level will result adjoining basin is poor the State may in concentration of salt residue over like to transfer the water of the rich surface, which will render the land unfit basin in its own basin which is not so for cultivation. Development of wateri- rich. ogging situation will also deteriorate 3) Systematic numerical data for declaring soil conditions and may convert large surplus and deficit basin are lacking. tract of fertile lands into a nonusable 4) Percapita water availability in various one. river basins is not available. Actual 10) Sedimentation in the bed of the stream flow data for major rivers and reservoir reduces the available storage their tributaries is non-existent. Rainfall capacity. data is not accurately recorded. No 11) From the economic point of view, systematic attempts have been taken valuable mineral deposits should not estimating surface run off. be allowed to be put out of use through 5) Large-scale superimposition of vast submergence or any other cause. infrastructure comprising dams, 12) Most of the link channels are likely to barrages and canals will create radical be aligned across direction of run-off changes on physiography of the which follows the general slope of country affecting the environment. country. So, serious drainage congestion is bound to happen in cautious approach is called for. In all upstream side of channel banks in spite fairness, the detailed plan should be made of construction of cross drainage worlds. public and national debate should be 13) Quality of water will be changed. initiated involving persons from all Alkaline water from northern India will disciplines including Engineers, Geologists, be joined with slightly acidic water of Geographers. Environmentalists, southern part, which may affect life Agronomists, Soil Scientists, Sociologists, habitat. Anthropologists and Financial Analysts. Moreover, it may be judicious to attempt similar smaller projects within the basin to Conclusions fulfil the needs of basin in an integrated and holistic approach before taking up the mega In view of water crisis looming large and project of Rs. 560000 crore. considering the economics of water in coming years, concept of interbasin transfer cannot be neglected. Desirability and Acknowledgements viability of the proposal should be properly clarified before implementation. An The author is grateful to Dr, M. K. extensive multidisciplinary study is essential Mukhopadhyay, Deputy Director General, before formulation of engineering design. NER, GSI for his kind permission to publish Proper environmental impact assessment the paper. Thanks are due to Dr. S. S. seems to be required. Considering the fact Ameta, Director, Engineering Geology that the dimension of impact will be Division II, NER, GSI for his kind inspiration extremely large, a well-informed and and valuable guidance.