『Abstract
　India is a vast country and is highly diversfied in terms of natural resources and socio-economic setup. Moreover, its water resources are unevenly distributed in space and time. With increasing population and increasing aspiration for improved standard of living, there is an acute pressure on the demand and availability of water. Though the idea of interlinking of rivers is not a new concept in India, it had rather persisted long back as much as in other countries of ancient civilization. National Water Development Agency (NWDA) has given the real shape to the proposal of the interlinking of rivers of the country. In India the river-linking project in a sensible and scientific manner will not only allow the prevention of the colossal wastage of a vitally important natural resource, mitigate the flood and inundation by detaining flowing surface water of rainy seasons, but also ensure availability of water to drier areas; combating both flood and drought simultaneously. Moreover, this project will generate 34,000 MW of hydropower and irrigation of an additional 35 million hectares (135,135 square miles) of land. Though linking of rivers may initially appear to be a costly proposition in ecological, geological, hydrological and economical terms, in the long run the net benefits coming from it will far outweigh these costs or losses. However, in the absence of any definite international legal framework, Bangladesh has raised objections against the project. This paper aims at looking at this long-term plan, the project proposal, its involvement and impact not only on the states of India, India as a whole, but also on its neighbouring nations which are linked with India through the waterways, and share the common climatic conditions and economic status.

Keywords: River linking; Peninsular rivers; Himalayan rivers; Ganga Plain; Rainwater harvesting; India』

Introduction
Origin of the proposal
　Peninsular rivers link
　Himalayan river link
Water resources and hydrological issues
　Hydrological aspects
　　Water supply
　　Salinity
　Geological aspects
　　Lithological constrains
　　Sedimentation
　　River regime
　　Geogenic problems
　Hydrogeological aspects
　Miscellaneous aspects
　　Impact on climate
　　Impact on environment and ecology
　　Impact on Nepal and Bangladesh
Need and alternate solutions
　Rainwater harvesting
　Prevent water wastage
　Controlling the excessive withdrawal of ground water
　Recycling and reuse of wastewater
　Use of natural geomorphology for recharging ground water reservoirs
　Efficient management of floods
　Encourage and educate the common man
　River linking versus rainwater harvesting
Advantages and disadvantages
　Agriculture sector
　Power sector
　Drought and flood mitigation
　Inland navigation
　Operational and maintenance cost
　Rehabilitation
　Employment
Conclusion
Acknowledgments
References

Fig. 1 Large variation in the availability of water in rivers of India (after, Patel 2004) 〔Misra,A.K., Saxena,A., Yaduvanshi,M., Mishra,A., Bhadauriya,Y. and Thakur,A.(2007): Proposed river-linking project of India: a boon or bane to nature. Environ. Geol., 51, 1361-1376.から〕

• Patel,C.C.(2004): Inter-linking of river systems. In: Water security and management of water resources. Department of Science and Technology, Government of India, Calcutta, pp 6-20.
• National Water Development Agency (NWDA)　　http://www.nwda.gov.in/
  　『National Water Development Agency (NWDA) was set up in July, 1982 as Autonomous Society under the Societies Registration Act, 1860, to carry out the water balance and other studies on a scientific and realistic basis for optimum utilisation of Water Resources of the Peninsular rivers system for preparation of feasibility reports and thus to give concrete shape to Peninsular Rivers Development Component of National Perspective Plan for Water Resources Development. In 1990, NWDA was also entrusted with the task of Himalayan Rivers Development Component of National Perspectives.
  FUNCTIONS OF NWDA:
  a) To promote scientific development for optimum utilization of Water Resources in the Country.
  b) To carry out detailed surveys and investigations of possible storage reservoir sites and interconnecting links in order to establish feasibility of the proposal of Peninsular Rivers Development and Himalayan Rivers Development Components forming part of National Perspective for Water Resources Development prepared by the then Ministry of Irrigation (now Ministry of Water Resources) and Central Water Commission.
  c) To carry out detailed studies about quantum of water in various Peninsular River Systems and Himalayan River Systems and which can be transferred to other basins/States after meeting reasonable needs of basin States in the foreseeable future.
  d) To prepare feasibility reports of various components of the scheme relating to Peninsular Rivers Development and Himalayan Rivers Development.
  e) To take such other actions the Society may consider necessary, incidental, supplementary or conducive to the attainment of above objectives.』

〔National Water Development Agency (NWDA)の『National Perspective Plan (NPP)』から〕