Fuzzy Evaluation of Flood Risk Rating in Laoshan District Based on GIS

The purpose of the present study was to reduce the losses caused by flood and to prevent them in advance, by taking Laoshan District, Qingdao City as an object. on the basis of COM GIS and the spatial analysis functions of GIS, we designed an evaluation model to develop flood risk evaluation system for Laoshan District. Using factor set, judgment set, membership function, and weight set established by the method of fuzzy comprehensive evaluation. The system can produce assessment results automatically after data input by the users, which is classed into 5 ranks, including "the most dangerous", "dangerous", 'normal', 'safe,' and "the safest". The results were obtained by the rating system most in common with the actual results, for example, Wanggezhuang street is in the most dangerous zone in the area. With good flexibility and performance, the method of the system can be promote into general crisis evaluation.