Study On Catastrophic Floods Scenario Design And Countermeasures Of Yongding River

Located on the northwestern edge of the North China Plain,Beijing is one of the regions that are frequently hit by rainstorms.The rainstorm-runoff relations of this city have changed a lot in recent years due to its special location,low-lying elevation,as well as increasing impermeable areas.The peak discharge caused by rains is growing significantly,challenging the city's ability to handle devastating floods.The scene construction of catastrophic event plays a leading role in handling cases,which is actually to analyze the risks and then give specific solutions to reduce the dangers or even get rid of them.Though the dangers may be different in time and space,basically they are natural disasters.Therefore,scene construction can represent cases of the same sort,looking for regulations and commonalities of the same kind of disasters,so as to offer scientific support.To handle the loopholes of Beijing's reaction to such disaster,this article shows the scene construction of extreme flood disasters,focusing on basin floods.Based on the literature of predecessors,this article investigates the Yongding River watershed,constructs an extreme flood scene,outlines emergency response and makes capability estimation,providing technical support for its emergency response management and safeguarding a sound flood control.Based on “bottom line thinking”,this article designs the technical segments for constructing a scene of extreme flood,presents the three points of constructing a scene-“event-solution-capability”,shows the key techniques of constructing such a scene,and reveals current flood control problems.It also carries out capability evaluation in six aspects,namely commanding and decision-making,social mobilization,forecasting and warning,information acquisition,emergency logistic support as well as engineer support.The article also quantifies the gaps of countering floods in Yongding River watershed,pointing out the countermeasures for leading policy makers,professional technicians and the public in this region.In accordance with the safety loopholes,it also sets up lists for loopholes and infrastructure projects.At the same time,this article believes the ecological projects along the river not only significantly shortens the flood width,but also restrains the natural enlargement of riverbed's cross section in flood season,leading to a high flood water level.Based on digital building of Yongding River,the article also provides digital support for its flood control.According to the results of extreme basin floods scene simulation,the author makes relative countermeasures,so as to improve the capability of extreme flood disaster response and provide strategy support for a safe flood control in the city.