Slope instability is a common problem for property owners in the Pacific Northwest because our hilly, wet conditions provide the ideal conditions for a landslide. It is important to remain vigilant in investigating slopes on and around your property, so you can recognize the warning signs of a landslide before it happens. Often, long before a major slide event the slope will show signs of danger or minor sliding.
Landslide Warning Signs
- Cracks or bulges in the ground, pavement or sidewalks near the slope
- Soil migrating away from foundations
- Structures such as decks, stairs and patios tilting or moving relative to the house
- Tilting or cracked floors/foundations
- Broken underground utilities
- Leaning , trees, walls or fences
- Sunken or down-dropped road beds
- Water saturated soil or changes in drainage patterns on a slope
- Newly sticking doors and windows
- Water seepage through the base of a slope
Landslide Contributing Factors
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- Water Saturated soils
- Removal of vegetation on or around the slope
- Improperly compacted fill during development
- Steep banks that have been undercut by rivers or improper development
- History of landslides in the area
If you observe any of these signs near a slope it may be prudent to leave the area and contact a professional civil engineer immediately for a slope assessment. If warning signs are very severe this may indicate an immediate threat to your property.