Analysis of the effects of the Xiaolangdi Reservoir on the lower Yellow River channel

摘要

The Xiaolangdi Reservoir, which began storing water in October 1999, is a multipurpose project that functions as a flood, ice and silt reduction measure. It also serves as a water supply, irrigation source and electricity generator for the surround area and the province. Given the severity of the sediment problem and the complexity of the Xiaolangdi Project, the Yellow River Conservancy Commission (YRCC) conducted a study of the operations of the Xiaolangdi Reservoir. This study included an operations schematic of water and sediment silt reduction for the Xiaolangdi Reservoir for the years 1999 and 2000. According to the schematic, during a flood event, the reservoir discharge polarizes with a lower discharge limit of 800 m~3/s and an upper limit set to 2600 m~3/s. It can be seen from the reservoir operations over the past two years that silt reduction has had an impact on the lower Yellow River. Water and sediment conditions in the lower Yellow River have changed while the scouring and silting of the channel have altered the channel configuration accordingly. This paper analyzes operations of the Xiaolangdi Reservoir, changes in water and sediment in the lower Yellow River, and changes in scouring and silting of sections of the river near hydrological stations.