Flood risk assessment for the central river basin of thailand

Abstract

The cumulative flooding frequencies and the cumulative floods’ consequences on lives and properties/ public utilities, observed over the 16-year period (2001–2016) in the Chao Phraya River Basin (CPRB) of Thailand, were used to preliminarily assess flood risks for the river basin. The estimated index (0–1) of flood risks was categorized into four classes, including low (0.12), moderate (0.13–0.32), high (0.33–0.62), and very high (0.63–1.00), and was mapped across the river basin using the ArcGIS program. Of the 151 districts located in the CPRB, four, three, and 10 districts showed very high, high, and moderate risks of flooding, respectively, whereas, the remaining 134 districts showed a low flood risk. Land use activities and man-made disturbances could influence the severity of the flood risk in the river basin. The findings are useful for the decision making by local administrations to prepare proper measures for flood risk management on a river basin scale.