Flood Risk Assessment in Small Watershed Based on Catastrophe Theory

Flood system is a complex system affected by many control factors and has typical system characteristics, such as irreversibility, fuzzy characteristics, gray characteristics, etc. Catastrophe theory is a well developed singularity theory, which has been initially applied in some leaping disaster systems. However, in the field of flood risk management, the application of catastrophe theory is relatively few. In this paper, a small watershed in the mountainous area of southwest China is taken for an example. The catastrophe assessment theory is adopted to conduct flood risk assessment. By analyzing the characteristics of the flood system and selecting flood risk factors, the flood risk assessment index system is established and the catastrophe theory flood risk assessment model is conducted, thus conducting flood risk zoning and management according to the assessment result, which provides a new reliable method for flood risk assessment and offers foundation for disaster reduction department.