Linear programming analysis in a tank irrigation system for near real representation and optimal allocation of area

There is a wide gap between an ideal situation and actual conditions existing in the field of irrigation management in any tank irrigation system in India. To bridge this gap, a near real time analysis through LP modeling of the existing situation and the best allocation policy is attempted for the Aralikottai tank system. The actual conditions are simulated at each sluice command level whereas the best operational policy is attempted for the entire system as a whole. The analysis is conducted separately for a drought year (1988) and a surplus year (1990) with the available five year data from 1988 to 1992. The major conclusions indicate that the late transplantations of the rice crop and the excess water application during the periods of water availability (leading to water stress during the last stages of crop maturity) are the causes of the meagre benefits in a drought year. Also, in a surplus year the excess water application over the entire cropping season resulted in under-utilization of land resources and moderate benefits. The existing status of irrigation can be improved to obtain the maximum benefits from the tank command area based on the quantification done.