Reservoir release policy for large irrigation system

This paper describes the formulation of a model for optimized crop and wate r planning decisions in an irrigation system in Thailand. It facilitates co nsultation in which representatives of stakeholders, officials, farmers, an d researchers can contribute to the decision making. Linear programming and the analytical hierarchy process are the principal modeling tools to optim ize the collective system objectives: productivity, equity, and security. T he results of the model are compared with observed events of one dry season . The optimized policy generated by the model suggested a diversified cropp ing pattern, which would decrease the water requirement by 16.4% and enhanc e net benefit per cubic meter of water used by 39.9%. The erratic water ava ilability from the reservoir and the operational procedures inside the syst em are reviewed, analyzing historical data in terms of reliability, resilie ncy, and vulnerability. These include lack of proper assessment of availabl e water, effective farmer organization, and prompt data processing and comm unication. Furthermore, for the effective implementation of an optimized ir rigation policy, a water release pattern of the storage reservoir has been suggested.