Landslide season commences...

in the Seattle area: What homeowners can do to prevent problems. While the primary natural trigger is water-saturated soils, here's a revealing fact from the linked article:

"A city landslide study found that 86 percent of landslides were caused by human activity such as excavation, fill placed on steep slopes, broken pipes and uncontrolled stormwater."

Recent years haven't been as bad as the winter of 1996-1997 which this on-line report details: Landslides Triggered by the Winter 1996-97 Storms in the Puget Lowland, Washington.