Reservoir impoundment influence on river flow regime

Abstract

Reservoir impoundment can have significant impact on natural flow regime of rivers. This paper takes Quwa reach of Bailong River located in Zhouqu County, Gansu Province as the study area. Analysis is done on changes happened to the flow regime of Bailong River from the dam to Lingba Village in Quwa Township, after the Daronglijie hydropower plant was built in Zhouqu County. The result indicates that the natural velocity of flow in this reach is above 2.0 m/s, but it decreased to 0.5 m/s after the dam was built. The velocity of flow declined, river level went up and sediment transport capacity of river dropped significantly, which is a major cause of serious river channel sedimentation.