Surface Water Management
Surface Water staff compiled the following information and internet references in an effort to increase landslide awareness for Skagit County residents.
Landslides occur in all U.S. states and territories and can be caused by a variety of factors including earthquakes, storms, volcanic eruptions, fire, and human modification of land. Landslides can occur quickly, often with little notice. The best way to prepare is to stay informed about changes in and around your home that could signal that a landslide is likely to occur.
In a landslide, masses of rock, earth or debris move down a slope. Debris and mud flows are rivers of rock, earth, and other debris saturated with water. They develop when water rapidly accumulates in the ground, during heavy rainfall or rapid snowmelt, changing the earth into a flowing river of mud or "slurry." They can flow rapidly, striking with little or no warning at avalanche speeds. They also can travel several miles from their source, growing in size as they pick up trees, boulders, cars and other materials.
Landslide problems can be caused by land mismanagement, particularly in mountain, canyon and coastal regions. In areas burned by forest and brush fires, a lower threshold of precipitation may initiate landslides. Land-use zoning, professional inspections, and proper design can minimize many landslide, mudflow, and debris flow problems (FEMA).
& Debris Flows (FEMA)
Hazards Program (USGS)
Hazard Information for the Puget Sound Region
of Ecology Landslide Website
of Ecology Slope Stabilization and Erosion Control Using Vegetation
Water and Groundwater on Coastal Bluffs: A Guide for Puget Sound Property
Owners (Department of Ecology, 1995) (PDF)
Management: A Guide for Puget Sound Bluff Property Owners (Department of Ecology, 1993) (PDF)
Stabilization and Erosion Control Using Vegetation: A Manual of Practice
for Coastal Property Owners (Department of Ecology, 1993)