A multipurpose reservoir real-time operation model for flood control during typhoon invasion

SummaryTo address the problem of a multipurpose reservoir flood control in Taiwan, this paper develops a reservoir real-time operation (RES-RT) model for determining the optimal real-time release during a typhoon. The RES-RT model consists of three sub-models: a quantitative precipitation forecast (QPF) model, which is developed to predict rainfall; a streamflow prediction (RTRL) model, which is developed to predict reservoir inflow; and a reservoir operation optimization (RESOP) model, which is developed to forecast the optimal reservoir release hydrograph. The RESOP model objectives are (1) maximizing the peak flow reduction at selected downstream control points; and (2) optimizing reservoir storage at the end of the flood. The constraints incorporate the three-flood-stage operation guidelines that are suitably applied in Taiwan. The developed RES-RT model has been applied to Shihmen reservoir system in Taiwan. Comparing the three scenarios of historical operations, current rules, and RES-RT model running, results show that the RES-RT model produces much better performance for all scenarios in terms of reducing the peak flow at the downstream control point as well as meeting the target reservoir storage at the flood ending. Consequently, RES-RT model demonstrates its effectiveness for estimating the optimal real-time releases.