Study On Risk Assessment And Prevention Methods Of Waterlogging Disaster

Under the background of rapid urbanization and global extreme climate,many factors such as the hardening of the underlying surface of cities and the destruction of the natural ecological pattern lead to increasingly frequent urban rainstorms,causing a series of threats to social economy,ecological environment and life and health.There is still much room for research on how to apply scientific,effective,green and systematic methods to deal with the occurrence of rain and waterlogging disasters.In this paper,quanzhou,a city with high incidence of rainstorm and waterlogging disasters,is selected as the research object.Combining with the thinking modes of urban and rural planning,hydrology,disaster science and other disciplines,the author USES geographic information system and hydrological analysis model to discuss the prevention and control methods of urban rainstorm and waterlogging by combining quantitative and qualitative analysis.The paper is carried out from four aspects.Firstly,the paper compares the simulation model,evaluation method,prevention and control theory and practice exploration of urban rainstorm and waterlogging disaster,and determines the risk assessment of urban rainstorm and waterlogging disaster at the urban scale by means of ArcGIS technology and index system evaluation.Risk assessment of drainage system at block scale by SWMM technique;In the second part,after determining the research method of the index system,the evaluation factors are selected and the comprehensive weight is assigned,and a complete evaluation system of the rainstorm and waterlogging disaster is constructed.According to the calculation formula of natural disaster risk,the risk index of rainstorm and waterlogging disaster in quanzhou was analyzed in GIS,and five risk levels were divided.Through the comparative relationship between urban construction status and risk level,the key factors affecting urban rainstorm and waterlogging disaster are found out,and the law of waterlogging disaster risk weakening from the southeast coast to the northwest mountainous area is summarized,which provides a theoretical basis for the following block scale research object selection and the construction of prevention and control strategies for planning.In the third part,the dynamic process of water accumulation in the block under the comprehensive action of different rainfall intensity,spatial elements and pipe network is deeply studied through the simulation and analysis of water catchment at high risk block scale.According to the situation of land use and water accumulation,the zoning optimization strategy combined with the development measures of low impact was put forward,and the simulation test was carried out again.In the fourth part,the author constructs the prevention and control methods of rainstorm and waterlogging in quanzhou city from three aspects:urban scale storm and waterlogging disaster planning,block scale water control method based on LID,waterlogging risk management and policy optimization.For quanzhou rainstorm waterlogging disaster risk research and prevention and control method,not only for the area of risk identification and disaster prevention planning provides the theoretical support,also through to discuss the relationship between urban space and rainstorm waterlogging disaster,enrich the urban and rural planning subject in research on the level of disaster prevention planning theory,coastal city for reducing waterlogging disaster loss,provides scientific basis to protect the safety of the city,has certain social significance.