The rainfall-runoff characteristics of urban and rural areas differ. Hence, major domestic design standards recommend using the rural basin rainfall-runoff models (the unit hydrograph method) for rural areas and the urban rainfall-runoff models (time-area method) for urban areas when estimating the amount of floods. Further, the guidelines for consultations on disaster impact assessment in Korea describe the selection of rainfall-runoff models according to basin types such as urban and rural areas. However, in complex watersheds where rural and urban basins coexist, the type of rainfall-runoff model is selected based on the modeler’s (or business operator’s) experiences rather than model selection guidelines. This study aims to analyze the impacts of uncertain design standards on disaster impact assessment in Korea. To this end, the parameters for each model (the unit hydrograph method, time-area method) were optimized using the measured datasets. The accuracy of the models was evaluated, as well as the appropriateness of flood reduction measures based on whether there was an assessment of downstream conveyance in development areas. The results of this study are expected to contribute to improving the reliability of the evaluation of flood reduction measures by assessing the accuracy of results in hydrological modeling and supplementing the uncertain flood estimation guidelines.
Disaster impact assessment of the underground hazardous materials pipeline
