Sustaining Agriculture through Modernization of Irrigation Tanks: An Opportunity and Challenge for Tamilnadu, India

The importance of controlled water supply is indispensable for the sustainability in low land paddy production, which varies enormously from region to region and country to country. What essential is the degree of importance given to the three elements of water management namely (i) resource management within the watershed (ii) conveyance to the crop fields and (iii) management within farm fields. While water losses in the paddy fields are to be discouraged, they need not necessarily amount to the losses to the watershed as a whole, if they are converted into groundwater and pumped back to the surface. In India, the second largest rice producing country of the world, 80% of water is used for irrigation.. There are around 40,000 irrigation tanks in Tamilnadu, India, irrigating about 0.63 million ha of paddy fields. Whatever, the shortcoming at their creation, existing irrigation tanks remain as an asset to the sustainability of paddy agriculture in Tamilnadu, provided their live storage is not reduced and the related irrigation facilities are not deteriorated to serve the purpose. Past experiences show that availability of surface water resources are not always reliable, which has turned the paddy farmer’s attention to the exploitation of ground water on a very much larger but manageable scale. The objective of this paper is to bring out the challenges and opportunities of the development strategies for the sustainability of paddy agriculture in the developing countries, (based on the experiences in Tamilnadu, India), where natural resources are plenty but financial resources are scarce. The performance of various types of small scale irrigation tanks in Tamilnadu are evaluated for their role in lowland paddy rice production, which lead to the invention of development strategies. These development strategies have both short term and long-term technical solutions. The short-term opportunities include on farm development works through modernization of existing irrigation facilities/structures and conjunctive use of surface and ground water resources. The long term challenge consist of establishing water grids connecting these modernized tanks in a chain to mitigate drought and flood at local level as well as encouraging the farmer’s participation in planning and management of these irrigation facilities for sustaining the paddy agriculture. It was found that evolving a comprehensive but integrated modernization strategies for the tanks is a complex task, due to the dynamic interactions of water which is routed through catchment, tank and field levels as well as because of other pertaining land based issues. Initial evaluations of such integrated modernization approaches adopted through Pilot studies indicate better environmental and economic benefits, contributing for sustainable development of paddy agriculture.