Small-scale natural disaster risk scenario analysis: a case study from the town of Shuitou, Pingyang County, Wenzhou, China

An empirical-based natural disaster risk assessment was carried out in a sub-national region of China, using the town of Shuitou, Pingyang County, Wenzhou, as the small-scale study area. Risk factors identified associated with the Typhoon Morakot rainstorm-flood event included hazard, vulnerability, and disaster loss, with the corresponding indicators being submergence depth (m), loss rate (%), and flood loss values (Yuan). As a frequent rainstorm-flood area, the maximum flood depth in Shuitou is 3.57 m, and the average loss rates for housing property and business assets reach 20 and 30 %, respectively. The average maximum loss ranges around 40,000-100,000 Yuan. The comprehensive disaster risk level depends on the respective strengths of the principal component factors. Extremely high-submersion-risk and very high-submersion-risk areas in Shuitou are found in the northwest, specifically along the GongYuan and Yuanlin roads, covering an area of 0.33 km(2), about 17.65 % of study areas. This small-scale natural disaster risk assessment encapsulates the principle of regional characteristics, case accumulation, long-term record. The evaluation results can be used as reference for regional temporary migration program design and implementation.