Impact analysis of cross-river bridge construction on hydrological elements at Datong Hydrological Station

To investigate the impact of the construction of Chizhou Yangtze River Highway-Railway Bridge in Anhui Province on the hydrological elements (such as water level, discharge, and sediment concentration) at the Datong Hydrological Station, this study systematically simulated and evaluated the changes in key elements at the station during both the construction and operation periods. A two-dimensional flow and sediment mathematical model was employed, integrated with an analysis of the engineering background and hydrogeological conditions, to quantify the influence of the proposed bridge on the hydrological elements at Datong Hydrological Station. Targeted mitigation measures were also proposed to ensure the accuracy, reliability and consistency of hydrological monitoring data. The results indicated that during the construction period, the bridge significantly affected the hydrological elements at Datong Hydrological Station, primarily manifested as increased water level fluctuations, exacerbated deviations in velocity distribution, and a shift in the relationship of single sample and cross section sediment, leading to reduced data consistency. In contrast, the impact during the operation period was relatively minor. Recommended countermeasures include increasing the frequency of topographic and discharge measurements, enhancing the analysis of flow-sediment relationships, and redefining parameters for flow and sediment measurements.