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

Landslides and flooding are the most frequent, costly and deadly disasters in Nepal

(Tianchi and Behrens, 2002).

Physiographical characteristics:

• Tectonically active • High relative relief• Monsoonal rainfall• Earthquakes, floods, GLOFS, landslides

Human perspective:

• Developing country• ~80% population classified as rural• Rapid population growth• Social inequality

Landslide Activity in Nepal

Chaku, Sindhupulchok District, Nepal

Community risk and vulnerability to landslide events?

The number of landslide related fatalities 1980-2003(Petley et al, 2007)

Trends in landslide activity

Increase in the number of landslides and associated fatalities since the early 1990’s.

Why?

Development of transport infrastructure:• Undercutting• Spoil disposal• Population relocation

(Gerrard and Gardner, 2000; Petley et al, 2007)

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Aims and Objectives

Vulnerability at the local level

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?

Aim: To investigate the vulnerability of rural communities to landslides in Central Nepal.

Tatopani, Central Nepal.

Research Strategies and Methodologies

A bottom-up, community based approach(Wisner, 2006)

Mixed methods

L/Ssusceptibilityassessment

Who is at risk?

Perceptions/ responses

Triggering factorsTerrain analysis

Geomorphologicalmapping

Aerial photograph/Satellite imagery

analysis

Household surveys

Scale/Frequency

Changes in Settlement

patterns

Semi-structuredinterviews

Participatorymapping

1 2 3

Required data:• landslide occurrence• susceptibility• exposure• response

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)

Creating taxonomies of “vulnerable” groups is problematic(Wisner, 2006).

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).

Preliminary Findings (2)

Why do people live in landslide prone areas?

1. No choiceAware 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)

No choice - aware of the risk but cannot afford to move.

Why do people live in landslide prone areas?

1) No choice

Case Study: A Tamang family, Chaku.

• 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:

• Visible cracks in house• Farmland destroyed.

Results and Analysis (2)

Advantages outweigh the risks

Why do people live in landslide prone areas?

2) Roadside location

Case Study: A Sherpa family, Chaku.

• House located at the bottom of a landslide prone slope.

• Migrated to Chaku ~18 yrs ago from a remote hillside village – better opportunities.

• Purchased the land they could afford.

Results and Analysis (2)

Unaware of the risks – “stable soil and mud”.

Why do people live in landslide prone areas?

3) Roadside location

Case Study: A high-caste family, Kodari

• Rent a house on the landslide prone slope in Kodari.

• Migrated from Pangthan ~ 2 years ago – better employment opportunities.

• Income – lorry driving/carry goods across the border.

• Believes Kodari is safer than other areas.

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: LarchaLandslide 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?

• Satellite imagery analysis • Field mapping (ground truth).

2. Are roadside settlements more vulnerable to landslide hazards than the remote hill villages?

• 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.