Optimization method for real-time river network control rules based on AGNES and K-Medoids algorithms

Abstract

[Objective] To address the delayed response of urban river networks to sluice and pump control rules, existing real-time control rules should be optimized to mitigate the backwater effect on drainage networks during storm events, thereby reducing flood risks. [Methods] First, a flood model was established using InfoWorks ICM to identify backwater-affected drainage outlets under different design storm events, followed by a quantitative analysis of surface inundation responses under both existing conditions and maximum drainage capacity. Then, a two-layer clustering model integrating AGNES and K-Medoids algorithms was established to determine river network control points based on the characteristics of backwater-affected drainage outlets. Finally, using these control points as control references, real-time control rules were optimized, and the performance of the proposed method was evaluated through observed storm events. A bidirectional tidal-influenced area in Cangshan District, Fuzhou City, was selected as a case study. [Results] The result showed that 23.73% of drainage outlets experienced backwater, and three river network control points were determined. Under the Super Typhoon Soudelor storm event, the optimized rules reduced the water head at river cross-sections by 3.51%, decreased the number of overflowing stormwater inlets by 1.53%, and lowered the surface inundation area and depth by 6.18% and 9.25%, respectively, compared to the original rules. [Conclusion] Identifying backwater-affected drainage outlets helps preliminarily locate flood-prone areas, and analyzing surface inundation responses provides a reliable basis for determining river network control points and optimizing real-time control rules. The comparative simulation of observed storm events verifies the effectiveness and advantages of the optimized rules in reducing river cross-section water head. Furthermore, it shows that updating sluice and pump control references is crucial for enhancing the responsiveness of urban river networks and mitigating flood risks. The proposed method provides a practical reference for optimizing river network operations and improving urban flood management.

Keywords

urban flooding / real-time river network control / backwater-affected drainage outlet / two-layer clustering model / river network control point / optimized rules