Analysis On The Adjustment Of The Benefit Of Limited Water Level Of Dong’e Reservoir Based On Risk

China is one of13severe water shortage countries in the world. But when in rainy season, to ensure river and dam safety, they have to discharge flood, resulting in a lot of waste of water resources. More than across the country, more than400cities of600medium-sized cities over country are in a serious water shortage. With the urbanization process and quality of people life increase, the per capita water consumption will increase in the future. The spatial and temporal uneven distributions have become a strategy problem on restricting the development of China. It’s urged to solve the problem that How to make full use of water resources and reduce the loss of floods, which is an important measure to achieve sustainable usage of basin water resources.Relying on measure that fully releases the potential of the regulation and storage, to convert the part of the flood into available water resources, have important significance to alleviate the shortage of basin water resources. Currently, reservoir is one of the most important engineering measures of regulating surface runoff. In the flood season, the part of the flood are reservoir up to control discharged flow, reducing the threat of flooding downstream and increasing the effectiveness of flood control and disaster mitigation; in non-flood season, reservoir water storage, can contain water, improve the ecology, develop the irrigation and aquaculture etc.. Therefore, the studies that, using the reservoir to regulate the flood resources on certain risk, appropriately adjust the reservoir flood limit level and develop a reasonable and feasible plan to regulate the floods, are necessary to optimize the operation system of reservoir and improve the utilization of water resources.Dong’e reservoir is the largest county small (1) reservoir, in2010by the provincial grants part, county-a part of the reservoir reinforcement, is mainly to the dam reinforcement, construction of spillway gate, spillway reconstruction, reconstruction of water hole, since Dong’e reservoir become the only county a reservoir gate control. After the reinforcement, the Dong’e reservoir has reached50years of design flood control standard, once in20years. In order to ensure maximum safety of reservoir design flood level, identified as49.00m, since after strengthening, reservoir has been running on the limited water level control. In recent years due to the abnormal climate, drought weather occurs, resulting in agricultural irrigation water volume increase, coupled with a base is located in the east of Langxi River middle reaches, seasonal spring recharge, the upstream water rich, perennial water, the reservoir conditions are good, so consider adjusting the East water reservoir flood limit water level, on the premise of safety of reservoir flood limit water level elevation, the Dong’e reservoir, reservoir storage capacity increases, can bring higher irrigation benefit, economic benefit, ecological benefit.Under the background of using flood as resource, Donge reservoir for example, the risks of the dam itself, downstream and upstream backwater flooded, were systematically investigated after elevation reservoir flood limit water level of0.5m,1.0m,1.5m. And determined that the dam was safe after elevation reservoir flood limit water level of0.5m,1.0m, but when flood limit water level elevated1.5m, the dam top elevation couldn’t meet the requirements for flood control. The benefits of0.5m,1.0m flood limited level elevation, such as flood control, disaster mitigation, economic social and ecology were analyzed. And1.0m flood limited level elevation was determined as the best plan, finally risk aversion are discussed through the Hood control regulation on reservoir. And proposed in the real work.