Simulation models for water resources management in Chikugo River basin

Tank model, one of simple water quantity models, is developed based on the concept of prototype model in order to simulate water quantity and water quality in Chikugo River basin. Chikugo River basin, the biggest one in Kyushu Island, is very famous in Japan for complicate water problems especially between irrigation water and drinking water etc. Though tank model for water quality analysis is rarely used in whole watershed, the developed tank model in this study can effectively simulate COD concentration of Chikugo River as well as its flow rate. And at the same time, unit COD loading of the existing pollutant sources is estimated. After calibrating the parameters of the water quantity and water quality, simulation results reveal that the developed tank model can be a tool for water resources management in Chikugo River basin.