Landslide Mitigation—How to Reduce the Effects of Landslides

Vulnerability to landslide hazards is a
function of location, type of human activity,
use, and frequency of landslide events. The
effects of landslides on people and structures
can be lessened by total avoidance of landslide
hazard areas or by restricting, prohibiting,
or imposing conditions on hazard-zone
activity. Local governments can reduce
landslide effects through land-use policies
and regulations. Individuals can reduce their
exposure to hazards by educating themselves
on the past hazard history of a site and by
making inquiries to planning and engineering
departments of local governments. They
can also obtain the professional services
of an engineering geologist, a geotechnical
engineer, or a civil engineer, who can properly
evaluate the hazard potential of a site, built or
unbuilt.
The hazard from landslides can be reduced
by avoiding construction on steep slopes
and existing landslides, or by stabilizing the
slopes. Stability increases when ground water
is prevented from rising in the landslide mass
by (1) covering the landslide with an impermeable
membrane, (2) directing surface water
away from the landslide, (3) draining ground
water away from the landslide, and (4) minimizing
surface irrigation. Slope stability is
also increased when a retaining structure and/
or the weight of a soil/rock berm are placed
at the toe of the landslide or when mass is
removed from the top of the slope.