Analyzing Downstream Flooding Effects Due to Small-Scale Reservoir Destruction Using Flow-R

Abstract

The frequency of abnormal weather patterns owing to climate change and the aging of reservoirs are contributing to an increase in dam failures, particularly of small-scale agricultural reservoirs. Dam collapses can lead to significant human and material damage downstream, even in the case of small-scale reservoirs. Therefore, alongside systematic maintenance of aging reservoirs, establishing emergency response plans for dam failures is imperative. However, application of existing dam failure models requires a substantial amount of time and resources, making it challenging to implement for small-scale reservoirs. In this study, the Flow-R model, which can estimate downstream damage areas using only digital topographic maps, was employed to calculate the extent of downstream damage resulting from the collapse of small-scale reservoirs. Five scenarios were analyzed based on the extent of reservoir destruction (ranging from 10% to 100%). The results revealed that the inundation area varied depending on the topography downstream of the reservoir. This study proposes an affordable and straightforward method for estimating damage downstream of reservoirs, even when limited data are available regarding the reservoirs. Thus, this study can be utilized in the development of emergency response plans for small-scale agricultural reservoirs.