Incorporating typhoon tracks for improved dynamic control of water level

Typhoons present both water resources and flood risks to coastal reservoirs. Forecasts of typhoon tracks are generally more accurate than precipitation over long lead times. However, existing dynamic control strategies consider precipitation forecasts without incorporating typhoon tracks. To address the issue, a dynamic control method is proposed by integrating both precipitation and typhoon forecasts. Typhoons are classified into categories based on their track characteristics and associated precipitation in the reservoir watershed. Dynamic water level control boundaries are established for each category. The Jiaokou Reservoir in Zhejiang, China, is selected for a case study. Results indicate that (1) the minimal distance of a typhoon from the reservoir and the corresponding precipitation are identified as control parameters, based on classification, (2) incorporating typhoon forecasts enables finer water level control with longer lead times compared to using precipitation forecasts alone, and (3) dynamic control integrating typhoon tracks and precipitation increases average water storage by 3.5 million m³ (5.6%) while maintaining the same flood control standards compared to dynamic control based solely on precipitation. The proposed method optimizes dynamic control strategies for reservoir water levels through typhoon and precipitation forecasts across varying lead times, effectively balancing flood risks and benefits.