TITLE:
Landslide Hazard Mapping of Nagadhunga-Naubise Section of the Tribhuvan Highway in Nepal with GIS Application
AUTHORS:
Arjun Raj Pandey, Farzad Shahbodaghlou
KEYWORDS:
Geology, Topography, Hazard Map, Hazard Rating, GIS (Geographic Information System)
JOURNAL NAME:
Journal of Geographic Information System,
Vol.6 No.6,
December
25,
2014
ABSTRACT: The aim of this project
was to prepare and study a hazard map of Nagadhunga-Naubise section of the
Tribhuvan highway. This section lies in the Middle Mountain region of Nepal.
For the preparation of the hazard map of the corridor three steps, initial
study, field investigation, and data analysis and presentation were carried
out. In the initial study, the collection of available data and review of the
literature were done. The base map was then prepared from the topographical
map. In the field investigation step, all information and maps prepared earlier
in the initial study were verified by field check. In the final step, prepared
and verified data were then analyzed for the hazard mapping. Topography
(gradient, slope shape and slope aspect), geology, drainage and land-use were
considered to be the major influencing factors in the slope stability.
Pre-assigned hazard rating method was used for hazard mapping of the study
area. The area was divided into equal facets. Then ratings of responsible
factors to the hazard were assigned to each facet and overlaid based upon a
predetermined rating scheme. Total estimated hazard was the sum of these
ratings for each overlay. Hazard map was prepared by using three categories as
low hazard, medium hazard and high hazard. The Geographic Information System
(GIS) was the main tool for the data input, analysis, and preparing of the
final hazard map. The hazard map showed the areas of different hazard potential
classes of; “low” with 32% portion, “Medium” with 51%, and “high” with 17%
portion.