The construction of large reservoir project has changed the temperature of discharge water, and has negative influence on the ecological environment of lower reaches. This study takes the Jiayan water conservancy project in Guizhou Province as an example, and uses the numerical simulation method to analyze the vertical characteristics of water temperature, and the influence on the discharge of low temperature water after the Jiayan reservoir is built. The research results show that in vertical direction, the temperature of Jiayan reservoir stratify stably. The temperature difference between surface layer and bottom layer changes significantly in different seasons, the surface water temperature mainly depends on sunshine, and the bottom water temperature is relatively stable. Compared with single-level water intake, multi-level water intake can effectually rise the temperature of discharge water in summer, decrease the temperature difference of discharge water and natural water, shorten the recovery distance of low-temperature discharge water, and reduce the negative influence on fish habitat in the lower reaches.
low temperature water