Debris Flow and Large-Scale Landslide Disaster Prevention Information Network

To assess the potential impact of unstable sediment on railway and highway bridges across Taiwan, the Agency of Rural Development & Soil and Water Conservation (ARDSWC) surveyed and delineated the "Unstable Sediment Outflow Potential Map" (referred to as the Unstable Sediment Potential Map), using all provincial highways and Taiwan Railway bridges as analysis targets, and setting a minimum delineation standard of 100 hectares of watershed area for unstable sediment outflow points. The analysis delineated a total of 325 unstable sediment outflow points, and adopted "Residual Slope Sediment," "River Channel Sediment," and "New Landslide" as evaluation indicators to calculate the amount of unstable sediment within the watershed and analyze the hazard of each sediment volume, thus obtaining the potential value and potential classification for each unstable sediment outflow point.