Journal of Korean Society of Agricultural Engineers ISSN:1738-3692(Print) 2093-7709(Online) 한국농공학회논문집

Water balance analysis in heightened reservoirs, which have been raised to ensure a stable supply of irrigation water and secure water against floods and heavy rainfall, is essential for evaluating water supply capacity and reservoir maintenance. The consecutively linked reservoir system, which involves preserving the existing embankment while constructing a new one, affects the water balance between the existing and new reservoirs. This study aims to analyze the linked water balance between reservoirs in a consecutively linked reservoir system using the DIROM (Daily Irrigation Reservoir Operation Model) model. Surveys were conducted to investigate actual water use, and multiple water supply quantities were estimated based on these findings. Methods to supplement missing data and improve the limitations of simulated inflow were proposed and applied, and the performance of the daily storage simulation was evaluated. By supplementing the missing water use data, the NSE (Nash-Sutcliffe Efficiency) of the Sonhang reservoir storage rate simulation improved by approximately 30%. Additionally, result of using inflow coefficients significantly enhanced the simulation performance for the Sonhang2 and Sonhang reservoirs. This study confirms the necessity of incorporating appropriate inflow coefficients in reservoir design to overcome the model’s tendency to overestimate inflow, highlighting the critical importance of quality control in observational data. The findings are expected to be useful for the design and analysis of future reservoir systems through embankment heightening.