Research Of River Flood Forecasting System Of Jinan

The frequently flash torrential rainfall in urban region often triggers floods along with the rapid urbanization and the accelerating global climate change,so the urban floods have been caught growing concern.With the mountain area in southern part and central area in Northern flat plain,Jinan only has xiaoqinghe as the drainage channel.Once encountered torrential rainfall,the river will not capable of draining floods,which easily evokes flood disasters and results in serious loss of life and property.Therefore,it's necessary to establish river flood forecasting system,which can early and accurately forecast the key section water level and discharge,deliver warning information in time,transfer people and property in advance to reduce loss from urban flood disaster.Based on the characteristics of runoff generation and confluence,the paper analyzes features of runoff generation,surface runoff,pipeline confluence and river confluence in urban region,then with the appropriate calculation method,we create the hydrological and hydraulic coupling model to simulate the process of rainfall runoff in Jinan,and construct a multifunctional river flood forecasting system with rainfall query,preplan query and river flood forecasting through Visual Studio2012,combining ArcGIS Engine development components and database.Establish mathematical model to simulate urban runoff generation and confluence.When establishing required model,the paper takes advantage of 3 common runoff generation and confluence model nowadays,namely hydrological model HEC-1 as calculating runoff and surface confluence,hydraulic model SWMM as calculating pipeline confluence and FLDWAV as calculating river flood routing.We couple the hydrological model and hydraulic model by loose coupling,calculate them separately,connect them through joint,and integrate the two kinds of model with interface program.Then,through the integrated model,with ArcGIS analyzing partial region in Jinan to extract related information and other related materials,we can set up the river flood forecasting system about Jinan.We also verify model parameter selection rationality and model reliability with several truth rainfall data and prototype observed hydrological data.According to Jinan historical rainfall information,we design Jinan typical rainfall process,and calculate short duration rainfall and long duration rainfall design conforming to Jinan.As well,based on the designed rainfall and historically typical rainfall,we make use of the established Jinan river flood forecasting model,simulate Jinan rainfall runoff process in different rainfall intensity,calculate the key river section's stage and discharge process during each time,and build Jinan river flood forecasting pre-plan database.From the system general structure and function requirement,Visual Studio 2012 as development tool,combining Arcgis Engine development components and databse,we exploit Jinan river flood forecasting system with the river flood forecasting model as core part,and realize functions,such as map viewer,map upload,rainfall query,river flood pre-plan query and river flood real-time forecasting.