Performance of irrigation canal before and after rehabilitation - A case study

摘要

Tamil Nadu in India has 7% of country's population but 3% of surface water resource. About 40% of population live below poverty line live in rural areas depending directly on agricultural activities. The state receives most of the rainfall during Octoberto December. Hence it is vital to conserve water when available. In the present scenarios tremendous changes have taken place in rainfall pattern, irrigation requirements and utilization of water. In future competing uses are likely to limit the water available for irrigation and these increasing demands could also force fundamental changes in irrigation system, cropping pattern and water use efficiency. Hence a study of performance of canal of an irrigation system which was constructed in the year 1978 was taken up. In this study the hydraulic carrying capacity of Left main canal of length 30 km which is the main component of the system that carries water for new command area of 3500 ha was assessed by the numerical model HEC-RAS. The details of thedata collected, analyses and methodology adopted are presented in this paper.