Stephanie JAQUET1, Karen I SUDMEIER-RIEUX2, Marc-Henri DERRON3, Michel JABOYEDOFF3 1Global Risk Forum, GRF, Davos; 2Independent, France; 3University of Lausanne, Institute of Geomatics and Analysis of Risk

1. Jaquet, S., Sudmeier-Rieux, K., Derron, M.-
H., Jaboyedoff, M.
University of Lausanne, Centre of Research on
Terrestrial Environment

2.  2 Case studies:
◦ Khariswara and Thang Thang villages in Dolakha
District, Central Nepal.
◦ Central-Eastern Nepal
◦ Average rainfall: ca. 2000mm, ca. 80% during the monsoon
season (June – September)
◦ 194 persons/ km2

3.  Landslides create most disaster losses in Nepal (ca.
100 per year)
 Underreported due to remoteness of landslides
 Impacting rural livelihoods to a greater extent than
other hazards
• Increase in the number of landslides and fatalities since the
1990s
 Why?
• Development of road network
• Undercutting of slopes
• Roadside settlements
• More intense rainfall (monsoon season)
Petley, 2011

4.  Combination of “bottom-up” vulnerability
assessment and quantitative participatory
approaches with a“top-down” geological risk
assessment
 case study approach:
◦ semi-structured interviews
◦ transect walks
◦ participatory risk
and resource mapping

5.  Participatory mapping
◦ risk perception of the locals and local knowledge
 Physical risk = H x E x V x W
◦ Common method for assessing risk (Fell et al. 1997)
 Composite risk = H x E x V [N, E, S, H, Ph] x W
◦ Using a composite estimation of vulnerability using
Natural, Economic, Social, Human and Physical components

7. Method High Middle Low
Community 16 1 0
Physical vulnerability 11 3 6
Composite vulnerability 11 7 2
Community risk map

8.  Composite risk map
 Physical risk map

9. April, 201 Sept,
0 2010
Jaquet/UNIL, 2010
March, Sept, 20
2011 11

10. Method High Middle Low
Community 7 7 19
Physical risk 1 17 15
Composite risk 4 14 15

11.  In both cases:
◦ The participatory method give the highest number of
houses at risk
◦ The physical risk method produced the lowest risk
assessment
◦ The composite risk produced an average risk
assessment
 The perceived risk is higher due to different
factors
◦ Recent landslide
◦ Willing for compensation
◦ The return period is not made explicit

12.  Participatory risk map
◦ highest estimation of risk areas, reflecting local perceptions of risk
◦ quite accurate
◦ information on land use, cracks, landslide history
 The physical method
◦ quick to assess
◦ do not take into account local knowledge
 The composite method
◦ takes into account five different components of vulnerability
◦ time consuming
◦ costly to assess
◦ but as it takes a systems perspective to assessing risk, it is more likely to lead to
sustainable outcomes for risk reduction measures in accordance with community
priorities.
 landslide risk assessment should integrate community risk assessments
to take into consideration local knowledge and perceptions.

13.  Importance of taking into account community
priorities for more sustainable risk reduction
measures

14. Thank you:
University of
Lausanne, Centre of
Research on
Terrestrial
Environment
Funding from:
Swiss National Science
Foundation 2009-
2011
Jaquet S., 2010

15. Khariswara landslide April 2012.
S.Devkota