Abstract: Primary water environmental problems in the Yangtze River Three Gorges' Reservoir were discussed. Some important results from recent research projects were reviewed in detail and some important scientific problems which need to be further studied more carefully in the near future were suggested. They are the water environmental modelling of the Yangtze River Three Gorges' Reservoir, the systematic engineering of pollution resources control, the eutrophication of the reservoir water, and the sediment of soil and sand in the reservoir, the pollution of heavy metals in the reservoir. Based on the River Water Quality Model (RWQM) suggested by the International Water Association (IWA), some points of view and methods for further research on the water environmental modelling in the Yangtze River Three Gorges' Reservoir were put forward. Based on a new lake eutrophication model，after forecasting the content of phosphorus，through the nonlinearity among the water eutrophication and its effecting factors, such as the nutrients, water depth, water flow rate, climate temperature, etc, the artificial neural network model was made, and the potential of the eutrophication of the reservoir water was primarily studied. Some primary results were presented and discussed. The process of soil and sand sediment and interaction of the sediment of soil and sand with heavy metals in the reservoir was discussed, some important water environmental problems in the Yangtze River Three Gorges′ Reservoir needed to be focussed in near future.

Key words: the Yangtze River Three Gorges′ Reservoir, water environmental capacity, eutrophication, water environmental modeling, water pollution control, soil and sand sediment