Modeling for Tank Cascade System Planning and Management: Case Study of Mamunugama Tank Cascade System, Kurunegala District

: The dynamics of tank cascade systems have been studied using simple water balance models. This paper presents the development of a system simulation model for a tank cascade system based on the principles of System Dynamics (SD), a mathematical modeling approach that could be used to study the behavior of dynamic systems. The model was developed for the Mamunugama tank cascade system comprising 06 tanks and 02 anicuts and located in the Kurunegala District, Sri Lanka. Modeling of all the water balance components of the tank cascade system is presented in detail. The model was calibrated using observed water levels at four tanks during the period from October 2020 to September 2021 covering a Maha Season and a Yala Season by comparing them with the model computed tank water levels. The model results provided valuable insights into the water balance components at each tank. The model has the potential to be used as a tool for optimizing the usage of the limited water resources in tank cascade systems for improved agricultural production. It can be used in planning tank rehabilitation, studying the impact of restoring abandoned tanks in addition to planning cultivation seasons in a scientific manner.