Abstract: As the source reservoir of the middle route of China’s South-to-North Water Diversion Project, the Danjiangkou Reservoir suffers from eutrophication threatens. Thus, it 

is necessary to develop an eutrophication model for local water resource management. In this study, a three-dimensional (3-D) eutrophication model for the Danjiangkou Reservoir was constructed. The model is different from the existing models for its embedded sediment diagenesis model with fifine grids, and it was calibrated and verifified by DO, NH4–N, TN,TP and Chl a. The calibrated model was applied to 9 scenarios regarding the variations of a number of key factors, such as water diversions, the increases in TN and the decreases in

inflflows. The spatial–temporal patterns of trophic status were analyzed and the potential areas of algae bloom were identifified. The results will be helpful for local water quality 

management and provide a valuable example for other similar research.

Keywords: Eutrophication model, Danjiangkou Reservoir, Sediment diagenesis model, South-to-North Water Diversion Project