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K. Shrestha et al.
7.1 Introduction
Nepal’s varied topography makes it susceptible to climate-related disasters and it
experiences a range of natural hazards, some of which occur annually, e.g., floods
and landslides (UNDP 2009). Disasters triggered by natural hazards cause heavy
loss of life, property, and unparalleled threat to sustainable development. With more
than 7,000 deaths, Nepal ranked 23
rd in terms of total natural hazard-related deaths
globally between 1988 and 2007 (Baruwal 2014); 11
th in the world in terms of
vulnerability to earthquakes; 30
th in terms of water-induced hazards such as flood
and landslides (UNDP 2009), and 20
th for the most multi-hazard prone countries
in the world (Dangal 2011). MoHA and DpNet-Nepal (2015) stated that the various
studies and reports over the last 33 years have shown that each year, floods, landslides,
fires, avalanches, and epidemics kill hundreds of people and destroy property worth
billions of rupees and the extreme weather events associated with heavy rainfalls are
the principal cause of cascading natural disasters in Nepal. Landslides in Nepal are
the country’s costliest and deadliest type of natural disaster, but their management is
still seen as low priority (IRIN 2013). Landslide susceptibility, vulnerability, and risk
maps are vital for disaster management and for planning development activities in the
mountainous country like Nepal. Despite high importance of landslide risk evaluation
for decision-making, comparatively minimal efforts have been made to establish
and systematically test methods for landslide risk assessment and understand their
advantages and limitations (Guzzetti 2012).
Ministry of Forest and Environment (MoFE 2010) stated that the overall vulnerability of Lamjung district in terms of disaster is very high with the index ranging from
0.100 to 0.787. The district is considered to be highly vulnerable to landslide, rainfall,
temperature, and glacial lake outburst flood (GLOF). The studies on landslide in the
river corridor should not be underestimated as it can cause a huge destruction. The
major purpose of this chapter is to assess the landslide susceptibility along the Chepe
River corridor within the boundary of Lamjung and Gorkha districts. Since this area
is unexplored in term of landslide assessments, this chapter will be a baseline for the
landslide assessments.
7.2 General Description of Chepe River Corridor
The study was conducted in the Chepe River, which lies in the border between the two
districts Gorkha and Lamjung (Fig. 7.1). The river originates from the Dudhpokhari
at an approximate elevation of 5300 m above sea level. The name of Chepe River is
linked to Nepal’s political history and the formation of the nation state, which offers
a rich context of institutional responses to landslides. It has a total catchment area of
308 km
2 at the confluence of Marshyangdi River. The total area of the river corridor
is about 47.301 km
2 considering the buffer of 500 m on both sides of the river.
The terrain is very rugged, precipitation distribution pattern seems to be very much
K. Shrestha et al.
7.1 Introduction
Nepal’s varied topography makes it susceptible to climate-related disasters and it
experiences a range of natural hazards, some of which occur annually, e.g., floods
and landslides (UNDP 2009). Disasters triggered by natural hazards cause heavy
loss of life, property, and unparalleled threat to sustainable development. With more
than 7,000 deaths, Nepal ranked 23
rd in terms of total natural hazard-related deaths
globally between 1988 and 2007 (Baruwal 2014); 11
th in the world in terms of
vulnerability to earthquakes; 30
th in terms of water-induced hazards such as flood
and landslides (UNDP 2009), and 20
th for the most multi-hazard prone countries
in the world (Dangal 2011). MoHA and DpNet-Nepal (2015) stated that the various
studies and reports over the last 33 years have shown that each year, floods, landslides,
fires, avalanches, and epidemics kill hundreds of people and destroy property worth
billions of rupees and the extreme weather events associated with heavy rainfalls are
the principal cause of cascading natural disasters in Nepal. Landslides in Nepal are
the country’s costliest and deadliest type of natural disaster, but their management is
still seen as low priority (IRIN 2013). Landslide susceptibility, vulnerability, and risk
maps are vital for disaster management and for planning development activities in the
mountainous country like Nepal. Despite high importance of landslide risk evaluation
for decision-making, comparatively minimal efforts have been made to establish
and systematically test methods for landslide risk assessment and understand their
advantages and limitations (Guzzetti 2012).
Ministry of Forest and Environment (MoFE 2010) stated that the overall vulnerability of Lamjung district in terms of disaster is very high with the index ranging from
0.100 to 0.787. The district is considered to be highly vulnerable to landslide, rainfall,
temperature, and glacial lake outburst flood (GLOF). The studies on landslide in the
river corridor should not be underestimated as it can cause a huge destruction. The
major purpose of this chapter is to assess the landslide susceptibility along the Chepe
River corridor within the boundary of Lamjung and Gorkha districts. Since this area
is unexplored in term of landslide assessments, this chapter will be a baseline for the
landslide assessments.
7.2 General Description of Chepe River Corridor
The study was conducted in the Chepe River, which lies in the border between the two
districts Gorkha and Lamjung (Fig. 7.1). The river originates from the Dudhpokhari
at an approximate elevation of 5300 m above sea level. The name of Chepe River is
linked to Nepal’s political history and the formation of the nation state, which offers
a rich context of institutional responses to landslides. It has a total catchment area of
308 km
2 at the confluence of Marshyangdi River. The total area of the river corridor
is about 47.301 km
2 considering the buffer of 500 m on both sides of the river.
The terrain is very rugged, precipitation distribution pattern seems to be very much