Abstract: By summarizing model test achievements of the intake and drainage project for powerplants along the Yangtze river, we presented the main sediment issues which should be considered for the intake and drainage project the river regime of intake and discharge segment, the variation of riverbed elevation at the head of intake, sediment concentration at the intake, non-depositing critical flow velocity, and incipient velocity. To ensure the safe and economical operation of powerplant, we proposed corresponding engineering measures to provide reference for the design of similar projects. These measures include selecting a proper location for drainage project according to the river regime, adjusting the elevation of drainage outlet based on model test results, adopting proper measures of water diversion, optimizing operation mode, and proposing critical non-silting flow velocity and incipient velocity of sediment in the pipe.

Key words: hydraulic engineering, powerplant, water intake and drainage project, sediment problems, non-silting critical flow velocity, incipient velocity of sediment