The Application Of Staged Limited Level Of Reservoir During Flood Season And Seasonal Flood Periods Classification In The Dongfeng Reservoir

China is one of the countries in most water resources shortage. In the north of China, the situation is especially serious. With the increase of China population and the development of society and economy, the amount of water resources utilization and polluted water have been rising while the environment quality is deteriorating. This situation has become a main constraining factor of national social-economical continuable development. Therefore, flood water factor of great significance for relieving the crisis of water resources shortage and improving the environment quality which can be realized through fully excavation the potentiality of reservoirs storage based on scientific-technical advance while the flood control risk doesn't increase.During the real-time operation of reservoirs ,the limit water level is such an important and sensitive index that it directly affects how to reasonably mitigate the contradiction between flood control and benefits of reservoirs. If the limited water levels for flood control during flood control during flood season are set to be high, it is advantageous for water storage and disadvantageous for flood control and vise versa. In order to resolve this paradox, flood limited level adjusting is selected as the object.The Dongfeng reservoir is selected as study odject.Based on it,some key problems focusing on adjustment of staged limited level of reservoir during flood season,such as season flood period partition,staged design flood computation and staged flood limited level adjusting are investigated.Based on analysis of average monthly rainfall of many years, Meanwhile, complemented by many quantitative analytical methods, fuzzy set analytical means, system assembling method, fractal method. Then,a scheme of flood season partition of Dongfeng reservoir is proposed.By the guide line of ABS, using the P-III distribution curve. Based on the former synthesis consideration ,some experience factors carry on the suitable revision. According to the flood season partition scheme, new achievements of design flood of Dongfeng reservoir are put forward by tran-periodical sampling. Using the interval of different period of time and the same frequency control enlargement means to obtain different stage design flood. Listing many limited level of reservoir during flood season plans. Using a-hundred-year return period of the design flood and a-thousand-year return period of the design flood to do simulation attemper. Under the premise of not increasing the reservoir flood prevention risk, choosing the highest water to be the best limited level of reservoir during flood season plan. Thus, flood resources can be used more effective.