Download - Lanslides tam 2013-04
Landslide: refers to the downward sliding of huge quantities of land mass
which occur along steep slopes of hills or mountains and may be sudden or slow
when part of a natural slope is unable to support its own weight.
MAIN FACTORS OF LANDSLIDES
I. Natural Factors
(i) Gravity
(ii) Geological factors
(iii) Heavy and prolonged rainfall
(iv) Earthquakes
(v) Forest fire
(vi) Volcanoes
(vii) Waves
II. Anthropogenic Factors
Human actions most notably those that affect drainage or
groundwater, can trigger landslides
(i) Inappropriate drainage system
(ii) Cutting & deep excavations on slopes for buildings, roads,
canals &mining
(iii) Change in slope/land use pattern, deforestation, agricultural
practices on steep slopes
RECENT LANDSLIDESUTTARAKHAND LANDSLIDE
• June 16, 2013 – Kedarnath, Uttarakhand
• more than 5,700 casualties
AFGHANISTAN LANDSLIDE
On2 May 2014 at Ab Barak, Badakhshan, Afghanistan
• 350-500 casualities• 4,000 people displaced
• 30 July 2014• Malin, Ambegaon taluka, Pune district, Maharashtra, India
• 136• 100+ missing
MALIN LANDSLIDE
• 2 August 2014• Sunkoshi, Sindhupalchok District, Nepal
• 156+casualities• Rescue efforts ongoing
SUNKOSHI LANDSLIDE
• 20 August 2014• Hiroshima Prefecture, Japan• 50+ casualities• 38+ missing, deadliest
landslides in Japan in 42 years
HIROSHIMA LANDSLIDE
Mitigation Measures
Site-Specific Mitigation Measures
1. Proper drainage management
2. Bio-engineering and Afforestation
3. Early Detection
4. Slope stability measures
The slope can be stabilized by one or a combination of
any or all of the following methods:
• Remove the landslide soil material
• Shear keys with drainage
• Buttress
• Removal of top
• Retaining Walls
• Steel nets or wire meshes
• Soil Nails
Landslide Hazard Mitigation Programme
• In order to prevent and mitigate the landslide risk, national
initiatives are required or strengthened to address the
following aspects:
1. Landslide Hazard Zonation(LHZ )
2. Mapping and monitoring of active landslides/vulnerable
slopes
3. Early Warning Systems
4. Awareness generation
Additional advice for specific locations:Before the Disaster
• Get a ground assessment of your property
• Minimize home hazards
• Doors/windows stick or jam for the first time, new cracks appear ,bulging ground appears
at base of a slope, ground slopes downward in one direction and may begin shifting in
that direction under your feet; faint rumbling sound increases in volume as landslide
nears
• Make evacuation plans, planning at least two routes allowing for blocked and closed roads
• Develop an emergency communication plan and ask an out-of-state relative or friend to
serve as the family contact
• Purchase flood insurance.
•
DURING THE DISASTER
If indoors:
Stay inside and get cover under a sturdy
piece of furniture.
If outdoors:
• Try to get out of path of mudflow
• Run to nearest high ground in a
direction away from path
• If rocks and other debris are
approaching, run for 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.
• Be cautious of sinkholes
AFTER THE LANDSLIDE
• Stay away from slide area
• Check for injured and trapped persons and
give first aid where needed
• Listen to battery-operated radios for
emergency information
• Remember flooding may occur after a
mudflow or landslide
• Check for damaged utility lines and report
damage to the utility company
• Check the building foundation, chimney,
and surrounding land for damage
• Replant damaged ground as soon as
possible since erosion caused by loss of
ground cover can lead to flash flooding.