Disaster Zone

5 Landslide Prevention Tips Plus — When to Get Out

Land movement can be costly in many ways.

by Eric Holdeman / November 10, 2016

Just last night I appeared on a local TV Station, KCPQ-13 here in the Seattle area. The topic was landslides. I wasn't able to cover all the the things listed below, but I tried to hit the high points. See my talking points below:

Here is a list of talking points I can use — I did come up with a few tips that homeowners can do to help prevent shallow slides:

• Landslides in the Puget Sound area normally occur during the months of January and February, after the ground gets saturated from winter rains.
• Slides are caused by water, gravity and generally a layer of clay that lets loose.
• If the record rains of October continue (and for 2016 Washington is 10” of rain above normal) then we could have problems.
• The best way to avoid landslides is not to live or work in an area that has a landslide history.
• Seattle has over a 100-year history of mapping where landslides have occurred. The Seattle Office of Emergency Management has a hazard map that includes landslides as one hazard.
o Avoid those hazard areas.
o Those million-dollar views can sometimes be very expensive.

• Land movement is not covered by the normal homeowners policy. Those special hazard policies are very expensive. Lloyds of London is one of the few who offers policies.
• To prevent shallow slides, you can do a few things on slopes that are on your property:
1.  Maintain as much vegetation as possible on the slope to help retain the soil.
2.  Do not put yard waste on the slope.
3.  Do not add additional water from downspouts to slopes from storm water runoff being directed to a hillside.
4.  Do not have an irrigation system on a hillside.
5.  Don’t locate swimming pools near a slope.

• For deep seated slides and damage, you need to consult with a geotechnical engineer. Remediating damages can be very expensive. Homeowners in the winter of 1996/97 walked away from some homes that had damages.
-Watch for new cracks in your foundation, driveway or just in the earth.
-If you hear your home creaking and things snapping or popping, get out and evacuate immediately.
-It could be multiple homes being impacted, not just yours.
-Contact 911. An inspection can only be done in daylight hours.

When looking at properties to purchase, you can look for leaning trees or trees with a bend in them that indicate there was a previous slide at that location.