Modeling and Pilot-Scale Experiment of Hydrodynamic Regulation to Improve the Water Quality of a Plain Urban River Network: A Case Study of Changzhou, China

Abstract

One-dimensional modeling of the hydrodynamic river networks of plain urban rivers has been employed to optimize operating regulations in these river networks. However, pilot-scale experiments are still lacking for the validation of hydrodynamics obtained by modeling to improve water quality. In this study, a pilot-scale experiment combined with theoretical calculation was conducted to determine both the hydrodynamics and water quality in the Hutang area of Changzhou, China. The simulation results showed that using high-performance pumps on the border to drain the river beyond it could increase the frequency of water replenishment. The results of the pilot-scale experiment are consistent with the simulation. Moreover, only in condition (c) does the water of the Wuyi canal flow into the Wunan river. With the exception of turbidity, the highest number of rivers with improved water quality tables occurred in this condition. Based on the response mechanism between the flow rate and the water quality, a flow rate within the range of 0.12 m/s to 0.28 m/s can help reduce comprehensive pollution. This study successfully enhanced the hydrodynamic regulation and water quality of the rivers in the Hutang region using technologies combined with simulation and pilot-scale experiments.