Study On The Theory And Methods For Flood Management In A Watershed

Based on the review and summarization of papers in the field of flood control and disaster reduction, the study on flood management is conducted. Aim at the flood management in a watershed; the guidelines, basic theory, countermeasures and steps are studied in the macro-sense. Then, some concrete methods are studied for the need of flood management of the Wei River Basin.It is pointed out by analysis that the idea of flood management is the demand of modern social-economical from flood control, which means that not only to control the flood and to mitigate the disaster caused by flood, but also to protect the ecological environment. The essential spirit is to realize "human being get along with the nature harmoniously". On the basis of watershed functions and the relationship between economic exploitation and the sustainable development in a watershed, directed by previously researches, a theoretical system of decision-making support for watershed management is put forward, in comparison with the old ones the system is expanded in some sense and has certain innovative property. On the summary of practical experience in flood disaster reduction, the existed problems are pointed out, and the countermeasures are put forward.The existed optimal models for flood management are summarized; especially the real time optimal operation models for reservoir and their solution methods are discussed. The simulation model for flood routing along the river channel is studied, and a simulation system is established on computer base. The model is applied to flood peak operation on the upper section of Wei River in Shaanxi, and the visualization is realized. The system has some advanced features and is suitable to use in practice. On the basis of analysis of existed floodcontrol and disaster mitigation system, flood management decision-making support system is put forward.The control area of the Wei River Basin is rather large with diverse climate feature; the suitable hydrological forecasting models for Feng-Jia-Shan and Hei-He Reservoirs are studiedand applied in practice. The GIS and the graphics interchange technique are researched in detail, which promote the forecasting method ahead. Because of serious sedimentation for the downstream section of the Wei River, the conventional forecasting method cannot get satisfactory results. The artificial neural network (ANN) method is studied for use in river channel flood forecasting, the result show that the method can be applied in practice.Water quality is an important issue for flood management study, in the thesis the estimation of non-point source pollution load and simulation are researched in consideration of water quality monitoring situation. The water quantity and quality relation method is put forward, which is a kind of new method and applicable in practice.On the basis of above studies, the strategy for flood management development is discussed. The studies are summarized and some suggestions for the future research are put forward.