2024 Volume 12 Issue 1 Article ID: 23-00171
In recent years, rainfall intensity in Japan has shown an upward trend, and sediment inflow disasters caused by mountain streams are increasing in number. As there are a significantly large number of mountain streams along railway lines, considerable time and effort are spent on local surveys for identifying dangerous mountain streams. Additionally, as there are a variety of diverse factors such as terrain and different geological features that collectively determine the hazard posed by mountain streams, risk-level assessments are not consistent among technicians. Above all, the risk-level assessment of upstream areas located in positions widely separated from the railway tracks and dispersed over a wide area require a huge amount of time and effort, and there may be a large disparity among the assessments made by engineers. Therefore, in this paper, we describe a simple method of evaluating the risk level of mountain streams in upstream areas using uniform criteria, without requiring local surveys. In concrete terms, we developed a scoring sheet that could assess the risk level mainly using quantitative data from a digital evaluation model (DEM). Through numerous comparisons, it was shown that the evaluation obtained using the DEM-scoring table was almost the same as the evaluation provided by local surveys.
