Dynamics of morphometric and hydraulic parameters of the Amudarya River channel downstream the Tuyamuyun hydroscheme

Abstract

The construction of large water reservoirs on level rivers has dramatically changed the nature and dynamics of channel processes in the upstream and downstream rivers. The purpose of the research is to study the relationship between the morphometry of the riverbed and the parameters of the waterworks rigged by the reservoir. To analyze the dynamics of the flow's channel morphometry and hydraulic elements, the lower course of the Amu Darya River, which is characterized by intense channel processes, was chosen. The study was carried out using field data on the Tuyamuyun gauge, located 1.8 km below the hydroelectric complex. The period for the last 25 years is covered, and 6 multi-year periods are selected from these. As a result of data analysis from long-term field studies and hydrometric measurements on the Tuyamuyun hydraulic section of the Amu Darya River, functional relationships have been established between the morphometric parameters of the channel and the hydraulic parameters of the flow. The relationship between the roughness of the channel and water flow is ambiguous. This is explained by the fact that the target is in the zone of the general spreading of the channel, and the bottom of the channel was observed to sink. When establishing the hydraulic resistance of the downstream, i.e., the relationship between the morphometric parameters of the channel and the hydraulic parameters of the flow, it is possible to predict changes in the water level and the state of water intake facilities. According to forecasts, it is possible to determine the type of event that allows for the supply of estimated flow rates through water intake facilities located in general erosion of the Tuyamuyun water reservoir.