The landslide problem is at least as damaging and widespread as that of flooding. When a heavy rain causes a landslide, the tremendous momentum of the water and stone can destroy bridge supports, roads, buildings and even fields under cultivation.
土石流是指堆積在集水區坍塌地的活動土石，一旦發生大雨和河床逕流，便順坡下流，衝力之大，可以帶走及沖毀橋樑、田地、道路、房舍等建物。