Estimation Model of Lake Level in Lake Ikeda

Hydrologic budget of a lake as a water resources

Abstract

The accurate evaluation of lake level is essential in managing a lake as a fresh water resource. In this study, a model to estimate lake level was developed and tested for Lake Ikeda by hydrologic budget analysis during 31 years from 1967 to 1997. Discharge from the lake catchment area and leakage from the lake bottom were estimated based on the Tank Model and Darcy's law, respectively. The model parameters for hydrogeologic properties around the lake catchment area and the lake bottom were calibrated by the SCE-UA (Shuffled Complex Evolution) method. From 1967 to 1980, the estimated lake level roughly agreed with the measured one. By re-calibrating the parameters for changes in the conditions of the hydrologic setting, the estimated lake level agreed well with the measured one from 1983 to 1997. The model developed in this study can be useful in the water management of Lake Ikeda.