Areas that
are generally prone to landslides
-
Old
and/or recent existing landslides,
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Base
or top of slopes
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Base of minor drainage hollows
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Base or top of an old fill slope
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Base or top of a steep cut slope
Areas generally safe from landslides
-
Hard, non-jointed bedrock that has not moved in the past
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Flat-lying areas away from slopes and steep river banks
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The nose of ridges, set back from the tops of
slopes
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Sticking
or jamming of doors
or windows.
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Appearance
of cracks in plaster, tile, brick, or foundations.
-
Pulling
away from the building of outside walls or stairs.
-
Slow
development of widening cracks on the ground or on paved areas
such as streets..
-
Breakage
of underground utility lines.
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Appearance
of bulging ground at the base of a slope
-
Emergence
of flowing ground water in new sites.
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Sudden
decrease in creek water levels though rain is still falling or
just recently stopped.
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Tilting
or moving of fences, retaining walls, utility poles, or trees.
-
Faint
rumbling sound that increases in volume as the landslide nears.The
ground slopes downward in one specific direction and may begin
shifting in that direction under your feet.
Immediate steps for imminent Landslide
Actions to be taken before Intense Rainfall
-
Become
familiar with the land around you. Slopes where landslides or debris
flows have occurred in the past are likely to experience
them in the future.
-
Buildings
should be located away from known landslides, debris flows, steep
slopes, streams and rivers, intermittent-stream
channels, and
the mouths of mountain channels.
-
Observe
the patterns of storm-water drainage on slopes near your home,
and watch especially the places were runoff water converges, increasing
flow over soil-covered slopes. Observe the hillsides around your
home for any signs of land movement, such as small landslides or
debris flows or progressively tilting trees.
-
Contact
your local authorities to learn about the disaster management response,
and develop your own emergency plans for your family and business.
During
Intense Rainfall
-
Be
observant. Many landslide and debris flow fatalities occur when
people are sleeping. Listen to radio for warnings of intense rainfall.
Intense short bursts of rain may be particularly dangerous, especially
after longer periods of heavy rainfall and damp weather.
-
Unusual
sounds might indicate moving debris, such as trees cracking or
boulders knocking together. A trickle of flowing or falling
mud or debris may precede larger landslides. Be alert for any
sudden increase or decrease in water flow in streams or channels.
Such
changes may indicate landslide activity upstream, so be prepared
to move quickly.
-
If
you live in areas susceptible to landslides and debris flows, consider
leaving if it is safe to do so. If you remain at home, move to
a part of the house farthest away from the source of the landslide
or debris flows, such as an upper floor, but keep an escape route
open should it become necessary to leave the house.
-
Be
alert when on the roads. Embankments along roadsides are particularly
susceptible to landslides. Watch the road for collapsed pavement,
mud, fallen rocks, and other indications of possible landslides
or debris flows.
- Be alert for signs indicating land movement. Landslides can occur
weeks or months after intense storms.
- Mudflows
tend to flow in channels, but will often spread out over a floodplain.
They generally occur in places where they have occurred before.
- Landslide and
mudflows usually strike without warning. The force of rocks, soil,
or other debris moving down a slope can devastate
anything in its path. Take the following steps to be ready.
- Plant ground cover
on slopes and build retaining walls.
- In mudflow areas,
build channels or deflection walls to direct the flow around buildings.
- Remember: If
you build walls to divert debris flow and the flow lands on a neighbor's
property, you may be liable for damages.
Precautions
to be taken during landslides
-
Try
and get out of the path of the landslide or mudflow.
-
Run
to the nearest high ground in a direction away from the path.
-
If
rocks and other debris are approaching, run for the nearest
shelter such as a group of trees or a building.
-
If
escape is not possible, curl into a tight ball and protect
your head.
-
Stay
away from the slide area. There may be danger of additional slides.
-
Check
for injured and trapped persons near the slide area. Give first
aid if trained.
-
Remember
to help your neighbors who may require special assistance--infants,
elderly people, and people with disabilities.
-
Listen
to a battery-operated radio or television for the latest emergency
information.
-
Remember
that flooding may occur after a mudflow or a landslide.
-
Check
for damaged utility lines. Report any damage to the utility company.
-
Check
the building foundation, chimney, and surrounding land for damage.
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Replant
damaged ground as soon as possible since erosion caused by loss
of ground cover can lead to flash
flooding.
-
Seek
the advice of geotechnical expert for evaluating
landslide hazards or designing corrective
techniques
to reduce landslide risk.
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