Why Do Landslides Occur?
Why do landslides occur?
1. Abundance of accumulatedmaterials.
2. Sufficient amount of water.
3. High enough grade of a slope.
When those three main conditionsare present, a debris flow may occur. However, a “debris flow” is not the samething as a “debris flow disaster.” A debris flow is a natural phenomenon, whilea debris flow disaster is when the debris flow causes casualties, damage tobuildings, bridges, and public constructions, and loss of life or property.
What do yellow and red alerts forlandslides mean?
Yellow alert: the “forecastedrainfall” is greater than the local “landslide warning reference value.”
Red alert: “actual rainfall” isgreater than the local “landslide warning reference value.”
When a red landslide alert isissued for the area, do the residents have to be mandatorily evacuated?
Evacuation can be determined basedon actual rainfall by the township or village head. However, if there is anevacuation order, it is recommended that life should take priority, and thatevacuation be implemented.