Landscape, livelihoods and risk:
A study of community vulnerability to landslide
events in a dynamic mountain environment
Katie Oven, D. Petley, J. Rigg, C. Dunn and N. Rosser
Landslide Activity in Nepal
Chaku, Sindhupulchok District, Nepal
Physiographical characteristics:
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Tectonically active
High relative relief
Monsoonal rainfall
Earthquakes, floods, GLOFS, landslides
Human perspective:
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Developing country
~80% population classified as rural
Rapid population growth
Social inequality
Landslides and flooding are the most frequent, costly and deadly disasters in Nepal
(Tianchi and Behrens, 2002).
Trends in landslide activity
Increase in the number of landslides and
associated fatalities since the early 1990’s.
140
Terai Plain districts
Number of landslide fatalities
120
Hill districts
Mountain districts
100
Why?
80
60
40
20
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
1981
1980
0
Year
Development of transport infrastructure:
• Undercutting
• Spoil disposal
• Population relocation
(Gerrard and Gardner, 2000; Petley et al, 2007)
The number of landslide related fatalities 1980-2003
(Petley et al, 2007)
Community risk and vulnerability to landslide events?
Aims and Objectives
Aim: To investigate the vulnerability of rural
communities to landslides in Central Nepal.
Key questions:
• Who are the vulnerable groups?
• Why do people live in landslide prone areas?
• How are physical risks perceived and
understood?
• How do people respond to landslide risk?
Tatopani, Central Nepal.
Vulnerability at the local level
Research Strategies and Methodologies
Required data:
• landslide occurrence
• susceptibility
• exposure
1
• response
Mixed
methods
L/S
susceptibility
assessment
Terrain analysis
Geomorphological
mapping
2
Triggering factors
Aerial photograph/
Satellite imagery
analysis
Scale/
Frequency
3
Who is at
risk?
Household
surveys
Semi-structured
interviews
Changes in
Settlement
patterns
A bottom-up, community based approach
(Wisner, 2006)
Perceptions/
responses
Participatory
mapping
Methodologies:
• Birkmann et al. (2006)
• Wisner (2006)
• ICIMOD (2002)
Field Sites
Research location:
Upper Bhotekoshi Valley,
Sindhupulchok district, Central Nepal.
Roadside settlements:
Chaku, Larcha and Kodari
Hill villages:
Narayanthan, Marmin, Duguna and
Nadung
Upper Bhote Koshi Valley
Preliminary Findings (1)
Who occupies the landslide prone areas?
Landslide prone areas occupied by:
• high caste;
• occupational caste;
• hill tribe groups.
• relatively rich and
• relatively poor households.
No strong correlation between
poverty level and caste grouping.
Chaku (2006).
.
Creating taxonomies of “vulnerable” groups is problematic
(Wisner, 2006).
Preliminary Findings (2)
Why do people live in landslide prone areas?
1. No choice
Aware of the risks but unable to move.
2. Roadside location (aware)
Advantages of a roadside location outweigh the
risks.
3. Roadside location (unaware)
Unaware of the threat of landslide activity.
Kodari (2006).
Results and Analysis (2)
Why do people live in landslide prone areas?
1) No choice
Case Study: A Tamang family, Chaku.
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House located above the failed slope
Head of the household born in Chaku
Own house but no land
Income: sharecropping/day wage labour.
Evidence of slope movement:
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Visible cracks in house
Farmland destroyed.
No choice - aware of the risk but cannot afford to move.
Results and Analysis (2)
Why do people live in landslide prone areas?
2) Roadside location
Case Study: A Sherpa family, Chaku.
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House located at the bottom of a landslide
prone slope.
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Migrated to Chaku ~18 yrs ago from a
remote hillside village – better opportunities.
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Purchased the land they could afford.
Advantages outweigh the risks
Results and Analysis (2)
Why do people live in landslide prone areas?
3) Roadside location
Case Study: A high-caste family, Kodari
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Rent a house on the landslide prone slope in
Kodari.
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Migrated from Pangthan ~ 2 years ago – better
employment opportunities.
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Income – lorry driving/carry goods across the
border.
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Believes Kodari is safer than other areas.
Unaware of the risks – “stable soil and mud”.
Preliminary Findings (3)
How are physical risks perceived and understood?
1. The natural/scientific explanation
Landslides triggers:
• Heavy rain
• Soil properties
• River undercutting
• Deforestation
• Quarrying of slate
• Road construction
Preliminary Findings (3)
How are physical risks
perceived and understood?
2. The “supra-natural” explanation
Landslides are the work of the Gods angered by:
• the disrespect of the natural environment;
• the Sherpa community killing the sacred cow!
The Land God controls giant snakes that live under the
ground.
Snakes move - a landslide is triggered.
Preliminary Findings (4)
How do people respond to landslide hazard and risk?
Long term responses: individual/household level:
1. Do nothing
Unaware of the risks or Risk denial/rejection
Case study: Larcha
Landslide dam-break floods/debris flow hazards.
Passive acceptance of the risks
Case study: Chaku
“Landslides are uncontrollable” / “Acts of God”
More urgent needs.
Participatory mapping, Chaku.
Preliminary Findings (4)
How do people respond to landslide hazard and risk?
2. Take action to reduce loss
Case study: Chaku
Temporary migration during the
monsoon months/ construction of walls.
3. Other responses
Community level – emergency fund,
worshipping gods, scattering sacred soil.
Government/NGO - limited involvement
Road maintenance.
Ongoing Research
1. What is the impact of road construction on
landslide activity?
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Satellite imagery analysis
Field mapping (ground truth).
2. Are roadside settlements more vulnerable to
landslide hazards than the remote hill villages?
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Field visit to 4 remote hill villages
Investigate the risks faced by hill communities.
TopSat image Upper Bhotekoshi Valley,
Central Nepal (QinetiQ, 2007)
Conclusion
• Rapid rise in the incidence/impact of landslides
since 1990s
landscape modification?
Initial findings suggest:
• No strong correlation between locational vulnerability
and socio-economic status/caste grouping.
• Landslide prone areas occupied due to lack of choice,
advantages of roadside location and/or unaware of risks.
• Natural/“supra-natural” understanding of environment.
• Risk response reflects risk perception and adaptive
capacity.