The upper reaches of the Yangtze River feature numerous rapids and hazardous rapids,where navigable safety poses significant challenges.There is an urgent demand for monitoring hydraulic parameters and providing services to vessels navigating these channels,but there is a lack of practical application of suitable monitoring technologies.We analyze multiple flow monitoring technologies and their adaptability,conducting field comparison tests between unmanned aerial vehicle(UAV) radar-based flow measurement and UAV surface imaging velocimetry.Then we propose a framework for intelligent application.The results demonstrate that the UAV radar-based method can simultaneously measure flow velocity and water level with high accuracy,velocity measurements achieve over 96% precision,and water level errors are within 0.1 m,making it suitable for monitoring hydraulic parameters in rapids.The UAV imaging velocimetry method effectively captures planar flow fields,proving more applicable for monitoring complex flow patterns in hazardous rapids.By developing an intelligent service system and applying the integrated use of on-site water flow monitoring data and mathematical model calculations,timely,accurate,and more comprehensive water flow information support can be provided for shipping.