Abstract:
In India, landslides are the most frequently occurring disaster in the
regions of the Himalayas and the Western Ghats. They are mainly triggered either by
rainfall or earthquake or the combination of both, causing severe damage to human
life and infrastructure. This study presents a comprehensive use of the multi-criteria
decision-making (MCDM) method in landslide risk assessment for the Tehri area in
the state of Uttarakhand, India. The Tehri area is situated in the Lesser Himalaya of
Garhwal hills which lies in zone IV of seismic zoning map of India. Because of the
large-scale slope instability in the area, it has received the special attention of the
researchers. In the recent past,—many landslide hazards and risk zonation is carried
out for different regions in the Uttarakhand state. However, limited work is done
considering temporal factors such as seismic ground shaking, rainfall, and seismic
amplification at surface level. The DEM data is used to produce topographic characteristics such as slope, aspect, and relative relief. DEM data is also used for the
detailed drainage analysis which includes topographic wetness index (TWI), stream
power index (SPI), drainage buffer, and reservoir buffer. Seismic hazard analysis is
performed using the deterministic methodology to estimate the peak horizontal acceleration. The amplification factor is calculated using the non-linear site amplification
method. In this study, the analytical hierarchy process (AHP) is used to evaluate the
landslide hazard index which is used to generate landslide hazard zonation (LHZ)
map. Further, the landslide vulnerability assessment is done for the study area. The
vulnerability map of the study area is derived in terms of landuse/landcover (LULC)
using remote sensing data of Landsat 8 which can provide useful information that
helps people to understand the risk of living in an area.
